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1.  A positive-margin resection model recreates the postsurgical tumor microenvironment and is a reliable model for adjuvant therapy evaluation 
Cancer Biology & Therapy  2012;13(9):745-755.
Up to 30% of cancer patients undergoing curative surgery develop local recurrences due to positive margins. Patients typically receive adjuvant chemotherapy, immunotherapy and/or radiation to prevent such relapses. Interestingly, evidence supporting these therapies is traditionally derived in animal models of primary tumors, thus failing to consider surgically induced tumor microenvironment changes that may influence adjuvant therapy efficacy. To address this consideration, we characterized a murine model of local cancer recurrence. This model was reproducible and generated a postoperative inflammatory tumor microenvironment that resembles those observed following human cancer surgery. To further validate this model, antagonists of two pro-inflammatory mediators, TGFβ and COX-2, were tested and found to be effective in decreasing the growth of recurrent tumors. We appreciated that preoperative TGFβ inhibition led to wound dehiscence, while postoperative initiation of COX-2 inhibition resulted in a loss of efficacy. In summary, although not an exact replica of all human cancer surgeries, our proposed local recurrence approach provides a biologically relevant and reliable model useful for preclinical evaluation of novel adjuvant therapies. The use of this model yields results that may be overlooked using traditional preclinical cancer models that fail to incorporate a surgical component.
doi:10.4161/cbt.20557
PMCID: PMC3606205  PMID: 22617772
Surgical model; adjuvant therapy; cancer recurrence; immunotherapy; oncology; tumor microenvironment
2.  Liver resection for colorectal cancer metastases 
Current Oncology  2013;20(3):e255-e265.
Questions
Should surgery be considered for colorectal cancer (crc) patients who have liver metastases plus (a) pulmonary metastases, (b) portal nodal disease, or (c) other extrahepatic metastases (ehms)?
What is the role of chemotherapy in the surgical management of crc with liver metastases in (a) patients with resectable disease in the liver, or (b) patients with initially unresectable disease in the liver that is downsized with chemotherapy (“conversion”)?
What is the role of liver resection when one or more crc liver metastases have radiographic complete response (rcr) after chemotherapy?
Perspectives
Advances in chemotherapy have improved survival in crc patients with liver metastases. The 5-year survival with chemotherapy alone is typically less than 1%, although two recent studies with folfox or folfoxiri (or both) reported rates of 5%–10%. However, liver resection is the treatment that is most effective in achieving long-term survival and offering the possibility of a cure in stage iv crc patients with liver metastases. This guideline deals with the role of chemotherapy with surgery, and the role of surgery when there are liver metastases plus ehms. Because only a proportion of patients with crc metastatic disease are considered for liver resection, and because management of this patient population is complex, multidisciplinary management is required.
Methodology
Recommendations in the present guideline were formulated based on a prepublication version of a recent systematic review on this topic. The draft methodology experts, and external review by clinical practitioners. Feedback was incorporated into the final version of the guideline.
Practice Guideline
These recommendations apply to patients with liver metastases from crc who have had or will have a complete (R0) resection of the primary cancer and who are being considered for resection of the liver, or liver plus specific and limited ehms, with curative intent.
1(a). Patients with liver and lung metastases should be seen in consultation with a thoracic surgeon. Combined or staged metastasectomy is recommended when, taking into account anatomic and physiologic considerations, the assessment is that all pulmonary metastases can also be completely removed. Furthermore, liver resection may be indicated in patients who have had a prior lung resection, and vice versa.
1(b). Routine liver resection is not recommended in patients with portal nodal disease. This group includes patients with radiologically suspicious portal nodes or malignant portal nodes found preoperatively or intraoperatively. Liver plus nodal resection, together with perioperative systemic therapy, may be an option—after a full discussion with the patient—in cases with limited nodal involvement and with metastases that can be completely resected.
1(c). Routine liver resection is not recommended in patients with nonpulmonary ehms. Liver plus extrahepatic resection, together with perioperative systemic therapy, may be an option—after a full discussion with the patient—for metastases that can be completely resected.
2(a). Perioperative chemotherapy, either before and after resection, or after resection, is recommended in patients with resectable liver metastatic disease. This recommendation extends to patients with ehms that can be completely resected (R0). Risks and potential benefits of perioperative chemotherapy should be discussed for patients with resectable liver metastases. The data on whether patients with previous oxaliplatin-based chemotherapy or a short interval from completion of adjuvant therapy for primary crc might benefit from perioperative chemotherapy are limited.
2(b). Liver resection is recommended in patients with initially unresectable metastatic liver disease who have a sufficient downstaging response to conversion chemotherapy. If complete resection has been achieved, postoperative chemotherapy should be considered.
3. Surgical resection of all lesions, including lesions with rcr, is recommended when technically feasible and when adequate functional liver can be left as a remnant. When a lesion with rcr is present in a portion of the liver that cannot be resected, surgery may still be a reasonable therapeutic strategy if all other visible disease can be resected. Postoperative chemotherapy might be considered in those patients. Close follow-up of the lesion with rcr is warranted to allow localized treatment or further resection for an in situ recurrence.
doi:10.3747/co.20.1341
PMCID: PMC3671032  PMID: 23737695
Colorectal cancer metastases; liver resection; hepatic resection; chemotherapy; complete response; downstaging
3.  The preclinical therapeutic response of residual metastatic disease is distinct from its primary tumor of origin 
Cancer-related deaths are caused principally by recurrence and metastasis arising from residual disease, whose therapeutic responses has been suggested to be substantially different from primary tumors. However, experimental animal models designed for evaluating the therapeutic responses of residual disease are mostly lacking. To overcome this deficiency, we have developed a preclinical model that recapitulates the progression for advanced non-small cell lung cancer (NSCLC). An archived Lewis Lung Carcinoma mouse tumor, propagated only through serial in vivo transplantation and never adapted to cell culture, was stably labeled using lentivirus-encoded biomarkers, consistently expressed through an RNA polymerase II promoter. Labeled tumors were inoculated into syngeneic immunocompetent mice to ensure superior tumor-host interactions. Primary tumors were resected upon reaching a predetermined size, following by treatment in a setting akin to post-surgical first-line adjuvant chemotherapy and routine imaging to monitor the progression of pulmonary metastasis. We discovered that efficacious treatment, instead of reducing disease growth rates, significantly prolonged disease-free survival (DFS) and overall survival (OS). As in the clinic, cisplatin-based regimes were more effective in this model. However, the response of metastases to specific agents could not be predicted from, and often opposed, their effects on subcutaneous “primary” tumors, possibly due to their distinct growth kinetics and host interactions. We here introduce a clinically relevant model of residual metastatic disease that may more accurately predict the therapeutic response of recurrent, metastatic disease.
doi:10.1002/ijc.25978
PMCID: PMC3161145  PMID: 21312195
4.  Preoperative/Neoadjuvant Therapy in Pancreatic Cancer: A Systematic Review and Meta-analysis of Response and Resection Percentages 
PLoS Medicine  2010;7(4):e1000267.
Jörg Kleef and colleagues systematically reviewed studies on neoadjuvant therapy and tumor response, toxicity, resection, and survival percentages in pancreatic cancer and suggest that patients with locally nonresectable tumors should be included in neoadjuvant protocols.
Background
Pancreatic cancer has an extremely poor prognosis and prolonged survival is achieved only by resection with macroscopic tumor clearance. There is a strong rationale for a neoadjuvant approach, since a relevant percentage of pancreatic cancer patients present with non-metastatic but locally advanced disease and microscopic incomplete resections are common. The objective of the present analysis was to systematically review studies concerning the effects of neoadjuvant therapy on tumor response, toxicity, resection, and survival percentages in pancreatic cancer.
Methods and Findings
Trials were identified by searching MEDLINE, EMBASE, and the Cochrane Central Register of Controlled Trials from 1966 to December 2009 as well as through reference lists of articles and proceedings of major meetings. Retrospective and prospective studies analyzing neoadjuvant radiochemotherapy, radiotherapy, or chemotherapy of pancreatic cancer patients, followed by re-staging, and surgical exploration/resection were included. Two reviewers independently extracted data and assessed study quality. Pooled relative risks and 95% confidence intervals were calculated using random-effects models. Primary outcome measures were proportions of tumor response categories and percentages of exploration and resection. A total of 111 studies (n = 4,394) including 56 phase I–II trials were analyzed. A median of 31 (interquartile range [IQR] 19–46) patients per study were included. Studies were subdivided into surveys considering initially resectable tumors (group 1) and initially non-resectable (borderline resectable/unresectable) tumors (group 2). Neoadjuvant chemotherapy was given in 96.4% of the studies with the main agents gemcitabine, 5-FU (and oral analogues), mitomycin C, and platinum compounds. Neoadjuvant radiotherapy was applied in 93.7% of the studies with doses ranging from 24 to 63 Gy. Averaged complete/partial response probabilities were 3.6% (95% CI 2%–5.5%)/30.6% (95% CI 20.7%–41.4%) and 4.8% (95% CI 3.5%–6.4%)/30.2% (95% CI 24.5%–36.3%) for groups 1 and 2, respectively; whereas progressive disease fraction was estimated to 20.9% (95% CI 16.9%–25.3%) and 20.8% (95% CI 14.5%–27.8%). In group 1, resectability was estimated to 73.6% (95% CI 65.9%–80.6%) compared to 33.2% (95% CI 25.8%–41.1%) in group 2. Higher resection-associated morbidity and mortality rates were observed in group 2 versus group 1 (26.7%, 95% CI 20.7%–33.3% versus 39.1%, 95% CI 29.5%–49.1%; and 3.9%, 95% CI 2.2%–6% versus 7.1%, 95% CI 5.1%–9.5%). Combination chemotherapies resulted in higher estimated response and resection probabilities for patients with initially non-resectable tumors (“non-resectable tumor patients”) compared to monotherapy. Estimated median survival following resection was 23.3 (range 12–54) mo for group 1 and 20.5 (range 9–62) mo for group 2 patients.
Conclusions
In patients with initially resectable tumors (“resectable tumor patients”), resection frequencies and survival after neoadjuvant therapy are similar to those of patients with primarily resected tumors and adjuvant therapy. Approximately one-third of initially staged non-resectable tumor patients would be expected to have resectable tumors following neoadjuvant therapy, with comparable survival as initially resectable tumor patients. Thus, patients with locally non-resectable tumors should be included in neoadjuvant protocols and subsequently re-evaluated for resection.
Please see later in the article for the Editors' Summary
Editors' Summary
Background
Pancreatic cancer is the fourth leading cause of cancer-related deaths worldwide. It begins when a cell in the pancreas (an organ lying behind the stomach that produces digestive enzymes and hormones such as insulin that controls blood sugar levels) acquires genetic changes that allow it to grow uncontrollably and, sometimes, to spread around the body (metastasize). Because pancreatic cancer rarely causes any symptoms early in its development, it is locally advanced in more than a third of patients and has already metastasized in another half of patients by the time it is diagnosed. Consequently, on average, people die within 5–8 months of a diagnosis of pancreatic cancer. At present, the only chance for cure is surgical removal (resection) of the tumor, part of the pancreas, and other nearby digestive organs. This procedure—the Whipple procedure—is only possible in the fifth of patients whose tumor is found when it is small enough to be resectable, and even in these patients, the cure rate associated with surgery is less than 25%, although radiotherapy or chemotherapy after surgery (adjuvant therapy) can be beneficial.
Why Was This Study Done?
For patients whose tumor has metastasized, palliative chemotherapy to slow down tumor growth and to minimize pain is the only treatment option. But, for the many patients whose disease is locally advanced and unresectable at diagnosis, experts think that “neoadjuvant” therapy might be helpful. Neoadjuvant therapy—chemotherapy and/or radiotherapy given before surgery—aims to convert unresectable tumors into resectable tumors by shrinking the visible tumor and removing cancer cells that cannot be seen with the naked eye. Randomized phase III trials—studies in which groups of patients are randomly assigned to different interventions and specific outcomes measured—are the best way to determine whether an intervention has any clinical benefits, but no randomized phase III trials of neoadjuvant therapy for unresectable pancreatic cancer have been undertaken. Therefore, in this systematic review (a study that uses predefined criteria to identify all the research on a given topic) and meta-analysis (a statistical method for combining the results of several studies), the researchers analyze data from other types of studies to investigate whether neoadjuvant therapy for pancreatic cancer provides any clinical benefits.
What Did the Researchers Do and Find?
In their systematic review, the researchers identified 111 studies involving 4,394 patients in which the effects of neoadjuvant chemotherapy and/or radiotherapy on tumor response, tumor resectability, and patient survival had been investigated. They subdivided the studies into two groups: group 1 studies included patients whose tumors were considered resectable on preoperative examination, and group 2 studies included patients whose tumors were borderline resectable or unresectable. In their meta-analysis, the researchers found that similar percentages of the tumors in both groups responded to neoadjuvant therapy by shrinking or regressing and that about a fifth of the tumors in each group grew larger or metastasized during neoadjuvant therapy. In the group 1 studies, three-quarters of the tumors were resectable after neoadjuvant therapy (a decrease in the proportion of tumors that could be treated surgically) whereas in the group 2 studies, a third of the tumors were resectable after neoadjuvant therapy (an increase in the proportion of tumors that could be treated surgically). After resection, the average survival time for group 1 patients was 23.3 months, a similar survival time to that seen in patients treated with surgery and adjuvant therapy. The average survival time for group 2 patients after resection was 20.5 months.
What Do These Findings Mean?
The finding that the average survival time after neoadjuvant therapy and surgery in patients whose tumor was judged resectable before neoadjuvant therapy was similar to that of patients treated with chemotherapy and/or radiotherapy after surgery suggests that for patients with resectable tumors, neoadjuvant therapy will not provide any clinical benefit. By contrast, the finding that a third of patients initially judged unresectable were able to undergo resection after neoadjuvant therapy and then had a similar survival rate to patients judged resectable before neoadjuvant treatment strongly suggests that patients presenting with locally advanced/unresectable tumors should be offered neoadjuvant therapy and then re-evaluated for resection. Randomized trials are now needed to confirm this finding and to determine the optimum neoadjuvant therapy for this group of patients.
Additional Information
Please access these Web sites via the online version of this summary at http://dx.doi.org/10.1371/journal.pmed.1000267.
The US National Cancer Institute provides information for patients and health professionals about all aspects of pancreatic cancer (in English and Spanish), including a booklet for patients
The American Cancer Society also provides detailed information about pancreatic cancer
The UK National Health Service and Cancer Research UK include information for patients on pancreatic cancer on their Web sites
MedlinePlus provides links to further resources on pancreatic cancer (in English and Spanish)
Pancreatica.org, PancreaticDuct.org, and the Pancreatic Cancer Action Network give more information to pancreatic cancer patients, their families, and caregivers
doi:10.1371/journal.pmed.1000267
PMCID: PMC2857873  PMID: 20422030
5.  Post-recurrence survival of patients with non-small-cell lung cancer after curative resection with or without induction/adjuvant chemotherapy 
OBJECTIVES
Recently, the prognosis of patients with non-small-cell lung cancer (NSCLC) has improved, thanks to the standardization of adjuvant chemotherapy and the introduction of molecular-targeted drugs, notably epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors and other new anti-cancer agents. However, the survival characteristics and prognosis of patients with recurrent NSCLC after curative resection are not well understood.
METHODS
Of the 430 consecutive patients with NSCLC who underwent complete surgical resection at our institution between January 2004 and July 2011, we included 76 patients with recurrence whose post-recurrence treatment and outcome could be confirmed. We then retrospectively evaluated the effect of prognostic factors on post-recurrence survival.
RESULTS
There were 50 men and 26 women, and the median age at recurrence was 74.5 years. The median time from surgical resection to recurrence was 12.7 months. Thirty-eight of the 76 (50%) patients underwent multimodality treatment with surgery and preoperative and/or postoperative chemotherapy as their initial treatment. For recurrence, systemic chemotherapy was administered to 64 (84%) patients, and the disease control rate for first-line chemotherapy was 55%. The 1- and 2-year post-recurrence survival rates were 68.3 and 45.8%, respectively, and the median post-recurrence survival time was 17.7 months. Six independent prognostic factors were identified: wild-type EGFR, no adjuvant chemotherapy for the primary lung cancer, age ≥80 years at recurrence, a poor Eastern Cooperative Oncology Group performance status at recurrence, symptomatic at recurrence and no systemic chemotherapy for recurrence, which significantly decreased the post-recurrence survival.
CONCLUSIONS
The prognosis of patients with NSCLC recurrence after surgery is currently improving. Our results suggested two new prognostic factors, adjuvant chemotherapy and EGFR mutations, neither of which have been previously reported. Treatment strategies for postoperative recurrence should be established based on a more detailed subdivision of factors, such as histology and molecular markers, in the future.
doi:10.1093/icvts/ivs450
PMCID: PMC3548532  PMID: 23143203
Non-small-cell lung cancer; Post-recurrence survival; Adjuvant chemotherapy
6.  Fluorescence-Guided Surgery Allows for More Complete Resection of Pancreatic Cancer Resulting in Longer Disease-Free Survival Compared to Standard Surgery in Orthotopic Mouse Models 
Background
Negative surgical margins are vital to achieve cure and prolong survival in patients with pancreatic cancer. We inquired if fluorescence-guided surgery (FGS) could improve surgical outcomes and reduce recurrence rates in orthotopic mouse models of human pancreatic cancer.
Study Design
A randomized active-control pre-clinical trial comparing bright light surgery (BLS) to fluorescence-guided surgery (FGS) was utilized. Orthotopic mouse models of human pancreatic cancer were established using the BxPC-3 pancreatic cancer cell line expressing red fluorescent protein (RFP). Two weeks after orthotopic implantation, tumors were resected with BLS or FGS. Pre- and postoperative images were obtained with the OV-100 Small Animal Imaging System to assess completeness of surgical resection. Postoperatively, whole body imaging was done to assess recurrence and follow tumor progression. Six weeks postoperatively, mice were sacrificed to evaluate primary pancreatic and metastatic tumor burden.
Results
A more complete resection of pancreatic cancer was achieved using FGS compared to BLS: 98.9% vs. 77.1%, p=0.005. The majority of mice undergoing BLS (63.2%) had evidence of gross disease with no complete resections, whereas 20% of mice undergoing FGS had complete resection and an additional 75% had only minimal residual disease (p=0.0001). The mean postoperative tumor burden was significantly less with FGS compared to BLS: 0.08 ± 0. 06 mm2 vs. 2.64 ± 0.63 mm2, p=0.001. The primary tumor burden at termination was significantly less with FGS compared to BLS: 19.3 ± 5.3 mm2 vs. 6.2 ± 3.6 mm2, p=0.048. FGS resulted in significantly longer disease-free survival than BLS (p=0.02, HR=0.39, 95% CI: (0.17, 0.88)).
Conclusions
Surgical outcomes were improved in pancreatic cancer using fluorescence-guidance. This novel approach has significant potential to improve surgical treatment of cancer.
doi:10.1016/j.jamcollsurg.2012.02.021
PMCID: PMC3383387  PMID: 22632917
pancreatic cancer; orthotopic mouse models; surgery; fluorescence; resection; recurrence; survival
7.  Attacking Postoperative Metastases using Perioperative Oncolytic Viruses and Viral Vaccines 
Frontiers in Oncology  2014;4:217.
Surgical resection of solid primary malignancies is a mainstay of therapy for cancer patients. Despite being the most effective treatment for these tumors, cancer surgery has been associated with impaired metastatic clearance due to immunosuppression. In preclinical surgery models and human cancer patients, we and others have demonstrated a profound suppression of both natural killer (NK) and T cell function in the postoperative period and this plays a major role in the enhanced development of metastases following surgery. Oncolytic viruses (OV) were originally designed to selectively infect and replicate in tumors, with the primary objective of directly lysing cancer cells. It is becoming increasingly clear, however, that OV infection results in a profound inflammatory reaction within the tumor, initiating innate and adaptive immune responses against it that is critical for its therapeutic benefit. This anti-tumor immunity appears to be mediated predominantly by NK and cytotoxic T cells. In preclinical models, we found that preoperative OV prevents postoperative NK cell dysfunction and attenuates tumor dissemination. Due to theoretical safety concerns of administering live virus prior to surgery in cancer patients, we characterized safe, attenuated versions of OV, and viral vaccines that could stimulate NK cells and reduce metastases when administered in the perioperative period. In cancer patients, we observed that in vivo infusion with oncolytic vaccinia virus and ex vivo stimulation with viral vaccines promote NK cell activation. These preclinical studies provide a novel and clinically relevant setting for OV therapy. Our challenge is to identify safe and promising OV therapies that will activate NK and T cells in the perioperative period preventing the establishment of micrometastatic disease in cancer patients.
doi:10.3389/fonc.2014.00217
PMCID: PMC4130104  PMID: 25161958
metastasis; postoperative period; oncolytic viruses; viral vaccines; cancer; perioperative immunostimulation; natural killer cells; surgical stress
8.  Therapeutic strategy for postoperative recurrence in patients with non-small cell lung cancer 
World Journal of Clinical Oncology  2014;5(5):1048-1054.
Postoperative recurrence occurs in approximately half of patients with non-small cell lung cancer (NSCLC), even after complete resection. Disease recurrence after surgical resection reduces the patient’s life expectancy sharply. The prognosis after postoperative recurrence is considered to largely depend on both the mode of first recurrence (distant, locoregional or combined) and the treatment modality: (1) The majority of cases of postoperative recurrence involve distant metastasis with or without locoregional recurrence. Platinum-based systemic chemotherapy is practically accepted as the treatment for these diseases on the basis of evidence for original stage IV disease. The advent of both pemetrexed and molecular-targeted drugs has improved the survival of nonsquamous NSCLC and changed the chemotherapeutic algorithm for NSCLC; (2) Among patients with distant metastatic recurrence without locoregional recurrence at the primary tumor site, the metastasis is often limited in both organ and number. Such metastases are referred to as oligometastases. Local therapy, such as surgical resection and radiotherapy, has been suggested to be the first-line treatment of choice for oligometastatic recurrence; and (3) While locoregional recurrence is likely to cause troublesome symptoms, it is a potentially limited disease. Therefore, providing local control is important, and radiation is usually beneficial for treating local recurrence. In order to obtain better control of the disease and provide treatment with curative intent in patients with limited disease, the administration of concurrent platinum-based chemoradiotherapy is recommended according to the results of originally nonresectable stage IIIA and IIIB disease.
doi:10.5306/wjco.v5.i5.1048
PMCID: PMC4259931  PMID: 25493240
Non-small cell lung cancer; Postoperative recurrence; Distant metastasis; Oligometastases; Local treatment; Locoregional recurrence
9.  Metronomic oral topotecan prolongs survival and reduces liver metastasis in improved preclinical orthotopic and adjuvant therapy colon cancer models 
Gut  2012;62(2):259-271.
Objective
Advanced and recurrent diseases are the major causes of death in colon cancer. No standard preclinical model addresses advanced disease and spontaneous metastasis after orthotopic tumour growth. In this study, the authors report the establishment of such standardised orthotopic mouse models of colon cancer and their use in evaluating metronomic topotecan alone or in combination with standard chemotherapy.
Design
Human colon cancer cell lines, transfected with human chorionic gonadotropin and luciferase, were injected orthotopically into the caecal wall of severe combined immunodeficient mice, intrasplenically or subcutaneously. For adjuvant therapy, caecal resections were performed 3–5 weeks after tumour cell injection. Chemotherapy drugs tested included uracil/tegafur, folinic acid, oxaliplatin, topotecan, pazopanib and various combinations.
Results
Subcutaneous tumours showed exaggerated sensitivity to treatment by delayed tumour growth (p=0.002) and increased survival (p=0.0064), but no metastatic spread. Intrasplenic cell injection resulted in rapid and extensive but artefactual metastasis without treatment effect. Intracaecal cell injection with tumour take rates of 87.5–100% showed spontaneous metastases at clinically relevant rates. Metronomic topotecan significantly polonged survival and reduced metastasis. In the adjuvant setting, metronomic maintenance therapy (after FOLFOX-like induction) prolonged survival compared with vehicle controls (p=0.0003), control followed by topotecan (p=0.0161) or FOLFOX-like therapy (p=0.0003).
Conclusion
The refined orthotopic implantation technique proved to be a clinically relevant model for metastasis and therapy studies. Furthermore, metronomic therapy with oral topotecan may be promising to consider for clinical trials of metastatic colon cancer and long-term adjuvant maintenance therapy of colon cancer.
doi:10.1136/gutjnl-2011-301585
PMCID: PMC3553490  PMID: 22543158
Metastasis; orthotopic implantation; adjuvant therapy; cancer; abdominal surgery; colon carcinogenesis; colorectal carcinoma
10.  Adjuvant therapy with agonistic antibodies to CD134 (OX40) increases local control following surgical or radiation therapy of cancer in mice 
Tumor recurrence from residual local or micro-metastatic disease remains a problem in cancer therapy. In patients with soft-tissue sarcoma and patients with inoperable non-small cell lung cancer, local recurrence is common and significant mortality is caused by the subsequent emergence of metastatic disease. Thus, while the aim of the primary therapy is curative, the outcome may be improved by additional targeting of residual microscopic disease. We demonstrate in a murine model that surgical removal of a large primary sarcoma results in local recurrence in approximately 50% of animals. Depletion of CD8 T cells results in local recurrence in 100% of animals, indicating that these cells are involved in control of residual disease. We further demonstrate that systemic adjuvant administration of αOX40 at surgery eliminates local recurrences. In this model, αOX40 acts to directly enhance tumor antigen-specific CD8 T cell proliferation in the lymph node draining the surgical site, and results in increased tumor antigen-specific cytotoxicity in vivo. These results are also corroborated in a murine model of hypofractionated radiation therapy of lung cancer. Administration of αOX40 in combination with radiation significantly extended survival compared to either agent alone, and resulted in a significant proportion of long-term tumor free survivors. We conclude that αOX40 increases tumor antigen-specific CD8 T cell cytotoxic activity resulting in improved endogenous immune control of residual microscopic disease, and we propose that adjuvant αOX40 administration may be a valuable addition to surgical and radiation therapy for cancer.
doi:10.1097/CJI.0b013e3181ee7095
PMCID: PMC3563298  PMID: 20842057
CD134; Costimulation; Surgery; Radiation; CD8
11.  Management of Refractory Metastatic Anal Squamous Cell Carcinoma Following Disease Progression on Traditional Chemoradiation Therapy 
Case Study
Ms. S.G., a 56-year-old woman with a poorly differentiated squamous cell carcinoma of the anal canal, American Joint Committee on Cancer stage III (T2, N1, M0), was initially diagnosed in December, 2007 at an outside institution after she had noted blood in her stool for approximately 6 months. Her medical history was unremarkable. She had no known history of HIV or other sexually transmitted diseases. At the time of presentation, Ms. S.G. had an Eastern Cooperative Oncology Group performance status of 1 related to cancer-related pain. Her appetite and weight were both stable.
A complete colonoscopy demonstrated a large, immobile, ulcerated, firm, 4-cm lesion in the distal rectum, arising from the anal canal. Initial staging positron emission tomography/computed tomography (PET/CT) scan revealed a hypermetabolic inferior anorectal mass with left perirectal and presacral nodal metastases. There was no definite evidence of distant metastatic disease.
Ms. S.G. received chemoradiation treatment following her diagnostic studies, with a total dose of 45 Gy over 26 fractions to the pelvis with concurrent infusional fluorouracil (5-FU; 2, 450 mg over 7 days) and mitomycin C (12 mg/m2 on day 1) at an outside institution. However, during her chemoradiation therapy, Ms. S.G. experienced a 3-week treatment break due to severe radiation dermatitis, as recommended by her outside treating oncologist.
Upon treatment completion, Ms. S.G. underwent a biopsy of the anal canal, which revealed no evidence of residual malignancy. As recommended by her treating oncologist, she received four additional cycles of adjuvant infusional 5-FU in combination with leucovorin. Shortly thereafter, Ms. S.G. developed progressive pelvic pain. She underwent a second PET/CT scan, revealing mixed findings: interval resolution of abnormal standardized uptake value (SUV) activity at the primary tumor in the anal canal, but an increase in the size and SUV of nodal disease within the left perirectal and presacral regions. A CT-guided biopsy noted a perirectal abscess requiring drainage but was inconclusive for disease recurrence; Ms. S.G. was treated with IV antibiotics.
Six weeks later, repeat radiographic imaging noted additional changes suspicious for regional recurrence, which was biopsy-confirmed. Ms. S.G. was subsequently referred to MD Anderson Cancer Center for consideration of salvage pelvic exenteration.
On physical exam a mass was palpated in the left lower quadrant, but there was no evidence of inguinal adenopathy. On digital rectal exam there was notable external erythema with a fixed mass and moderate sphincter tone. A chest CT scan showed no definite evidence of metastatic disease, but an MRI of the abdomen/pelvis indicated the presence of a complex partially necrotic mass (7.6 × 4.9 × 7.3 cm3) extending to the rectosigmoid junction, inseparable from the left lateral bowel wall, with partial encasement of the bowel. In addition, there was infiltration of the left piriformis muscle and cervix consistent with local recurrence. She was referred to medical oncology and radiation oncology for consideration of reirradiation with concurrent neoadjuvant chemotherapy for palliation and possible surgical resection.
In early December 2008, Ms. S.G. received intensity-modulated radiation therapy (IMRT), with a total dose of 27 Gy over 18 fractions. She received concurrent infusional 5-FU at 300 mg/m2/day, from Monday to Friday, on the days of radiation. She also received a weekly bolus dose of cisplatin at 20 mg/m2. The intent was to treat to 30 Gy, but the patient deferred further treatment early due to anorectal irritation. She then underwent restaging with a PET/CT scan and a pelvic MRI in February 2009, revealing radiographic partial response of the known pelvic recurrence and reduced pelvic pain (Figures 1A and 1B). Figure 1 Figure 1. Contrast-enhanced axial MRI image of the lower pelvis. (A) Pretreatment, complex mass at the rectosigmoid junction measuring approximately 7.6 × 4.9 × 7.3 cm3. (B) Posttreatment, large necrotic mass measuring 3–4 cm in greatest dimension.
Unfortunately, in the interim, she developed multiple bilateral liver lesions and punctate pulmonary nodules consistent with distant disease (Figures 2A, 2B, and 3A). Figure 2 Figure 2. Contrast-enhanced axial CT images of the lung. (A) Subcentimeter nodular opacity in the left upper lobe. (B) Subcentimeter opacity in the right upper lung lobe. Figure 3 Figure 3. Contrast-enhanced axial CT image of the liver. (A) Pretreatment, multiple bilateral liver lesions. (B) Posttreatment, near-complete resolution of liver lesions.
Ms. S.G. proceeded to undergo systemic chemotherapy with carboplatin at an area under the concentration-time curve of 5 and paclitaxel at 175 mg/m2 day 1, every 21 days. She tolerated the treatment well. After three cycles of chemotherapy, radiographic imaging indicated a mixed response to treatment: interval resolution of the pulmonary nodules, stability of disease in the pelvic mass, but progression of the hepatic metastases.
Given Ms. S.G.'s continuing excellent performance status, further treatment was recommended. Based on recent published literature, a regimen of cisplatin at 80 mg/m2 day 1, vinorelbine at 25 mg/m2 day 1 (repeated every 28 days), and weekly cetuximab (VCC) at 250 mg/m2 was initiated. Remarkably, following three cycles of treatment, despite receiving multiple prior lines of chemotherapy, her restaging CT scan demonstrated complete radiographic response of the intrathoracic disease, stable response of the anorectal mass, and near-complete resolution of the hepatic lesions (Figures 3A and 3B).
Overall, Ms. S.G. had tolerated her treatment very well. Given her response and tolerability, she was evaluated again for curative surgical resection. However, she opted to receive the VCC regimen closer to home and was lost to follow-up. Unfortunately, we were unable to obtain medical records confirming if she indeed received additional treatment as recommended. Ms. S.G. was noted to have passed away due to progression of her disease approximately 6 months later.
PMCID: PMC4093318  PMID: 25031942
12.  Tumor-Immune Interaction, Surgical Treatment, and Cancer Recurrence in a Mathematical Model of Melanoma 
PLoS Computational Biology  2009;5(4):e1000362.
Malignant melanoma is a cancer of the skin arising in the melanocytes. We present a mathematical model of melanoma invasion into healthy tissue with an immune response. We use this model as a framework with which to investigate primary tumor invasion and treatment by surgical excision. We observe that the presence of immune cells can destroy tumors, hold them to minimal expansion, or, through the production of angiogenic factors, induce tumorigenic expansion. We also find that the tumor–immune system dynamic is critically important in determining the likelihood and extent of tumor regrowth following resection. We find that small metastatic lesions distal to the primary tumor mass can be held to a minimal size via the immune interaction with the larger primary tumor. Numerical experiments further suggest that metastatic disease is optimally suppressed by immune activation when the primary tumor is moderately, rather than minimally, metastatic. Furthermore, satellite lesions can become aggressively tumorigenic upon removal of the primary tumor and its associated immune tissue. This can lead to recurrence where total cancer mass increases more quickly than in primary tumor invasion, representing a clinically more dangerous disease state. These results are in line with clinical case studies involving resection of a primary melanoma followed by recurrence in local metastases.
Author Summary
Melanoma is a deadly skin cancer that invades into the dermis and metastasizes into the surrounding tissue. In clinical cases, surgical excision of the primary tumor has led to widespread and accelerated growth in metastases. We develop a mathematical model describing the basic process of melanoma invasion, metastatic spread, and the anti-tumor immune response. This model is formulated using partial differential equations that describe the spatial and temporal evolution of a number of different cellular populations, and it uses a realistic skin geometry. Using simulations, we examine the importance of the immune response when a primary tumor is spawning satellite metastases. We find that local metastases can be suppressed by the immune response directed against the primary tumor, but grow aggressively following surgical treatment. We also find that moderately metastatic tumors optimally activate the local immune response against disseminated disease, and in this case tumor excision may have profound effects on metastatic growth. We conclude that surgical perturbation of the immune response controlling local metastases is one mechanism by which cancer can recur. This could have implications as to the appropriate clinical management of melanomas and other solid tumors.
doi:10.1371/journal.pcbi.1000362
PMCID: PMC2667258  PMID: 19390606
13.  Gene Therapy for Brain Cancer: Combination Therapies Provide Enhanced Efficacy and Safety 
Current gene therapy  2009;9(5):409-421.
Glioblastoma multiforme (GBM) is the most common primary brain cancer in adults. Despite significant advances in treatment and intensive research, the prognosis for patients with GBM remains poor. Therapeutic challenges for GBM include its invasive nature, the proximity of the tumor to vital brain structures often preventing total resection, and the resistance of recurrent GBM to conventional radiotherapy and chemotherapy. Gene therapy has been proposed as a useful adjuvant for GBM, to be used in conjunction with current treatment. Work from our laboratory has shown that combination of conditional cytotoxic with immunotherapeutic approaches for the treatment of GBM elicits regression of large intracranial tumor masses and anti-tumor immunological memory in syngeneic rodent models of GBM. In this review we examined the currently available animal models for GBM, including rodent transplantable models, endogenous rodent tumor models and spontaneous GBM in dogs. We discuss non-invasive surrogate end points to assess tumor progression and therapeutic efficacy, such as behavioral tests and circulating biomarkers. Growing preclinical and clinical data contradict the old dogma that cytotoxic anti-cancer therapy would lead to an immune-suppression that would impair the ability of the immune system to mount an anti-tumor response. The implications of the findings reviewed indicate that combination of cytotoxic therapy with immunotherapy will lead to synergistic antitumor efficacy with reduced neurotoxicity and supports the clinical implementation of combined cytotoxic-immunotherapeutic strategies for the treatment of patients with GBM.
PMCID: PMC2864138  PMID: 19860655
Immunotherapy; apoptosis; cancer models; HMGB1; Flt3L; HSV1-TK
14.  Genomic Predictors for Recurrence Patterns of Hepatocellular Carcinoma: Model Derivation and Validation 
PLoS Medicine  2014;11(12):e1001770.
In this study, Lee and colleagues develop a genomic predictor that can identify patients at high risk for late recurrence of hepatocellular carcinoma (HCC) and provided new biomarkers for risk stratification.
Background
Typically observed at 2 y after surgical resection, late recurrence is a major challenge in the management of hepatocellular carcinoma (HCC). We aimed to develop a genomic predictor that can identify patients at high risk for late recurrence and assess its clinical implications.
Methods and Findings
Systematic analysis of gene expression data from human liver undergoing hepatic injury and regeneration revealed a 233-gene signature that was significantly associated with late recurrence of HCC. Using this signature, we developed a prognostic predictor that can identify patients at high risk of late recurrence, and tested and validated the robustness of the predictor in patients (n = 396) who underwent surgery between 1990 and 2011 at four centers (210 recurrences during a median of 3.7 y of follow-up). In multivariate analysis, this signature was the strongest risk factor for late recurrence (hazard ratio, 2.2; 95% confidence interval, 1.3–3.7; p = 0.002). In contrast, our previously developed tumor-derived 65-gene risk score was significantly associated with early recurrence (p = 0.005) but not with late recurrence (p = 0.7). In multivariate analysis, the 65-gene risk score was the strongest risk factor for very early recurrence (<1 y after surgical resection) (hazard ratio, 1.7; 95% confidence interval, 1.1–2.6; p = 0.01). The potential significance of STAT3 activation in late recurrence was predicted by gene network analysis and validated later. We also developed and validated 4- and 20-gene predictors from the full 233-gene predictor. The main limitation of the study is that most of the patients in our study were hepatitis B virus–positive. Further investigations are needed to test our prediction models in patients with different etiologies of HCC, such as hepatitis C virus.
Conclusions
Two independently developed predictors reflected well the differences between early and late recurrence of HCC at the molecular level and provided new biomarkers for risk stratification.
Please see later in the article for the Editors' Summary
Editors' Summary
Background
Primary liver cancer—a tumor that starts when a liver cell acquires genetic changes that allow it to grow uncontrollably—is the second-leading cause of cancer-related deaths worldwide, killing more than 600,000 people annually. If hepatocellular cancer (HCC; the most common type of liver cancer) is diagnosed in its early stages, it can be treated by surgically removing part of the liver (resection), by liver transplantation, or by local ablation, which uses an electric current to destroy the cancer cells. Unfortunately, the symptoms of HCC, which include weight loss, tiredness, and jaundice (yellowing of the skin and eyes), are vague and rarely appear until the cancer has spread throughout the liver. Consequently, HCC is rarely diagnosed before the cancer is advanced and untreatable, and has a poor prognosis (likely outcome)—fewer than 5% of patients survive for five or more years after diagnosis. The exact cause of HCC is unclear, but chronic liver (hepatic) injury and inflammation (caused, for example, by infection with hepatitis B virus [HBV] or by alcohol abuse) promote tumor development.
Why Was This Study Done?
Even when it is diagnosed early, HCC has a poor prognosis because it often recurs. Patients treated for HCC can experience two distinct types of tumor recurrence. Early recurrence, which usually happens within the first two years after surgery, arises from the spread of primary cancer cells into the surrounding liver that left behind during surgery. Late recurrence, which typically happens more than two years after surgery, involves the development of completely new tumors and seems to be the result of chronic liver damage. Because early and late recurrence have different clinical courses, it would be useful to be able to predict which patients are at high risk of which type of recurrence. Given that injury, inflammation, and regeneration seem to prime the liver for HCC development, might the gene expression patterns associated with these conditions serve as predictive markers for the identification of patients at risk of late recurrence of HCC? Here, the researchers develop a genomic predictor for the late recurrence of HCC by examining gene expression patterns in tissue samples from livers that were undergoing injury and regeneration.
What Did the Researchers Do and Find?
By comparing gene expression data obtained from liver biopsies taken before and after liver transplantation or resection and recorded in the US National Center for Biotechnology Information Gene Expression Omnibus database, the researchers identified 233 genes whose expression in liver differed before and after liver injury (the hepatic injury and regeneration, or HIR, signature). Statistical analyses indicate that the expression of the HIR signature in archived tissue samples was significantly associated with late recurrence of HCC in three independent groups of patients, but not with early recurrence (a significant association between two variables is one that is unlikely to have arisen by chance). By contrast, a tumor-derived 65-gene signature previously developed by the researchers was significantly associated with early recurrence but not with late recurrence. Notably, as few as four genes from the HIR signature were sufficient to construct a reliable predictor for late recurrence of HCC. Finally, the researchers report that many of the genes in the HIR signature encode proteins involved in inflammation and cell death, but that others encode proteins involved in cellular growth and proliferation such as STAT3, a protein with a well-known role in liver regeneration.
What Do These Findings Mean?
These findings identify a gene expression signature that was significantly associated with late recurrence of HCC in three independent groups of patients. Because most of these patients were infected with HBV, the ability of the HIR signature to predict late occurrence of HCC may be limited to HBV-related HCC and may not be generalizable to HCC related to other causes. Moreover, the predictive ability of the HIR signature needs to be tested in a prospective study in which samples are taken and analyzed at baseline and patients are followed to see whether their HCC recurs; the current retrospective study analyzed stored tissue samples. Importantly, however, the HIR signature associated with late recurrence and the 65-gene signature associated with early recurrence provide new insights into the biological differences between late and early recurrence of HCC at the molecular level. Knowing about these differences may lead to new treatments for HCC and may help clinicians choose the most appropriate treatments for their patients.
Additional Information
Please access these websites via the online version of this summary at http://dx.doi.org/10.1371/journal.pmed.1001770.
The US National Cancer Institute provides information about all aspects of cancer, including detailed information for patients and professionals about primary liver cancer (in English and Spanish)
The American Cancer Society also provides information about liver cancer (including information on support programs and services; available in several languages)
The UK National Health Service Choices website provides information about primary liver cancer (including a video about coping with cancer)
Cancer Research UK (a not-for-profit organization) also provides detailed information about primary liver cancer (including information about living with primary liver cancer)
MD Anderson Cancer Center provides information about symptoms, diagnosis, treatment, and prevention of primary liver cancer
MedlinePlus provides links to further resources about liver cancer (in English and Spanish)
doi:10.1371/journal.pmed.1001770
PMCID: PMC4275163  PMID: 25536056
15.  Chemotherapy for cholangiocarcinoma: An update 
Cholangiocarcinomas (bile duct cancers) are a heterogeneous group of malignancies arising from the epithelial cells of the intrahepatic, perihilar and extrahepatic bile ducts. Patients diagnosed with cholangiocarcinoma must be evaluated by a multidisciplinary team and be treated with individualized management. First of all, it is very important to define the potential resectability of the tumor because surgery is the main therapeutic option for these patients. Overall, cholangiocarcinomas have a very poor prognosis. The 5-year survival rate is 5%-10%. In cases with a potentially curative surgery, 5-year survival rates of 25%-30% are reported. Therefore, it is necessary to increase the cure rate from surgery, exploring the survival benefit of any adjuvant strategy. It is difficult to clarify the role of adjuvant treatment in localized and locally advanced cholangiocarcinomas. There are limited data and the role of adjuvant chemotherapy/chemoradiation in patients with resected biliary tract cancer is poorly defined. The most relevant studies in the adjuvant setting are one from Japan, the well known ESPAC-3 and BILCAP from the United Kingdom and a meta-analysis. We show the results of these trials. According to medical oncology guidelines, postoperative adjuvant therapy is widely recommended for all patients with intrahepatic or extrahepatic cholangiocarcinoma who have microscopically positive resection margins, as well as for those with a complete resection but node-positive disease. Clinical trials are ongoing. The locally advanced cholangiocarcinoma setting includes a heterogeneous mix of patients: (1) patients who have had surgery but with macroscopic residual disease; (2) patients with locally recurrent disease after potentially curative treatment; and (3) patients with locally unresectable disease at presentation. In these patients, surgery is not an option and chemoradiation therapy can prolong overall survival and provide control of symptoms due to local tumor effects. Nowadays, no neoadjuvant therapy can be considered a standard approach for the treatment of patients with cholangiocarcinoma. There are promising results and randomized trials are needed in patients with a metastatic cholangiocarcinoma. In systemic therapy, no single drug or combination has consistently increased median survival beyond the expected 8-12 mo. It is always recommended that patients enrol in clinical trials. Clinical trials have shown that the more standard chemotherapy for a first line regimen of gemcitabine plus cisplatin (or oxaliplatin as a potentially better tolerated agent) is superior to gemcitabine alone. Leucovorin-modulated 5-fluorouracil, capecitabine monotherapy or single agent gemcitabine are reasonable options for patients with a borderline performance status. After progression in patients with an adequate performance status, active regimens that could be considered include gemcitabine plus capecitabine, or erlotinib plus bevacizumab, for second line treatment.
doi:10.4251/wjgo.v5.i7.171
PMCID: PMC3731530  PMID: 23919111
Chemotherapy; Cholangiocarcinoma; Review; Oncology; Gemcitabine
16.  M-HIFU Inhibits Tumor Growth, Suppresses STAT3 Activity and Enhances Tumor Specific Immunity in a Transplant Tumor Model of Prostate Cancer 
PLoS ONE  2012;7(7):e41632.
Objective
In this study, we explored the use of mechanical high intensity focused ultrasound (M-HIFU) as a neo-adjuvant therapy prior to surgical resection of the primary tumor. We also investigated the role of signal transducer and activator of transcription 3 (STAT3) in M-HIFU elicited anti-tumor immune response using a transplant tumor model of prostate cancer.
Methods
RM-9, a mouse prostate cancer cell line with constitutively activated STAT3, was inoculated subcutaneously in C57BL/6J mice. The tumor-bearing mice (with a maximum tumor diameter of 5∼6 mm) were treated by M-HIFU or sham exposure two days before surgical resection of the primary tumor. Following recovery, if no tumor recurrence was observed in 30 days, tumor rechallenge was performed. The growth of the rechallenged tumor, survival rate and anti-tumor immune response of the animal were evaluated.
Results
No tumor recurrence and distant metastasis were observed in both treatment groups employing M-HIFU + surgery and surgery alone. However, compared to surgery alone, M-HIFU combined with surgery were found to significantly inhibit the growth of rechallenged tumors, down-regulate intra-tumoral STAT3 activities, increase cytotoxic T cells in spleens and tumor draining lymph nodes (TDLNs), and improve the host survival. Furthermore, M-HIFU combined with surgery was found to significantly decrease the level of immunosuppression with concomitantly increased number and activities of dendritic cells, compared to surgery alone.
Conclusion
Our results demonstrate that M-HIFU can inhibit STAT3 activities, and when combined synergistically with surgery, may provide a novel and promising strategy for the treatment of prostate cancers.
doi:10.1371/journal.pone.0041632
PMCID: PMC3404041  PMID: 22911830
17.  Inhibition of Chondrosarcoma Growth by mTOR Inhibitor in an In Vivo Syngeneic Rat Model 
PLoS ONE  2012;7(6):e32458.
Background
Chondrosarcomas are the second most frequent primary malignant type of bone tumor. No effective systemic treatment has been identified in advanced or adjuvant phases for chondrosarcoma. The aim of the present study was to determine the antitumor effects of doxorubicin and everolimus, an mTOR inhibitor on chondrosarcoma progression.
Methods and Findings
Doxorubin and/or everolimus were tested in vivo as single agent or in combination in the rat orthotopic Schwarm chondrosarcoma model, in macroscopic phase, as well as with microscopic residual disease. Response to everolimus and/or doxorubicin was evaluated using chondrosarcoma volume evolution (MRI). Histological response was evaluated with % of tumor necrosis, tumor proliferation index, metabolism quantification analysis between the treated and control groups. Statistical analyses were performed using chi square, Fishers exact test. Doxorubicin single agent has no effect of tumor growth as compared to no treatment; conversely, everolimus single agent significantly inhibited tumor progression in macroscopic tumors with no synergistic additive effect with doxorubicin. Everolimus inhibited chondrosarcoma proliferation as evaluated by Ki67 expression did not induce the apoptosis of tumor cells; everolimus reduced Glut1 and 4EBP1 expression. Importantly when given in rats with microscopic residual diseases, in a pseudo neoadjuvant setting, following R1 resection of the implanted tumor, everolimus significantly delayed or prevented tumor recurrence.
Conclusions
MTOR inhibitor everolimus blocks cell proliferation, Glut1 expression and HIF1a expression, and prevents in vivo chondrosarcoma tumor progression in both macroscopic and in adjuvant phase post R1 resection. Taken together, our preclinical data indicate that mTOR inhibitor may be effective as a single agent in treating chondrosarcoma patients. A clinical trial evaluating mTOr inhibitor as neo-adjuvant and adjuvant therapy in chondrosarcoma patients is being constructed.
doi:10.1371/journal.pone.0032458
PMCID: PMC3384598  PMID: 22761648
18.  Antitumor Activity of Rapamycin in a Phase I Trial for Patients with Recurrent PTEN-Deficient Glioblastoma 
PLoS Medicine  2008;5(1):e8.
Background
There is much discussion in the cancer drug development community about how to incorporate molecular tools into early-stage clinical trials to assess target modulation, measure anti-tumor activity, and enrich the clinical trial population for patients who are more likely to benefit. Small, molecularly focused clinical studies offer the promise of the early definition of optimal biologic dose and patient population.
Methods and Findings
Based on preclinical evidence that phosphatase and tensin homolog deleted on Chromosome 10 (PTEN) loss sensitizes tumors to the inhibition of mammalian target of rapamycin (mTOR), we conducted a proof-of-concept Phase I neoadjuvant trial of rapamycin in patients with recurrent glioblastoma, whose tumors lacked expression of the tumor suppressor PTEN. We aimed to assess the safety profile of daily rapamycin in patients with glioma, define the dose of rapamycin required for mTOR inhibition in tumor tissue, and evaluate the antiproliferative activity of rapamycin in PTEN-deficient glioblastoma. Although intratumoral rapamycin concentrations that were sufficient to inhibit mTOR in vitro were achieved in all patients, the magnitude of mTOR inhibition in tumor cells (measured by reduced ribosomal S6 protein phosphorylation) varied substantially. Tumor cell proliferation (measured by Ki-67 staining) was dramatically reduced in seven of 14 patients after 1 wk of rapamycin treatment and was associated with the magnitude of mTOR inhibition (p = 0.0047, Fisher exact test) but not the intratumoral rapamycin concentration. Tumor cells harvested from the Ki-67 nonresponders retained sensitivity to rapamycin ex vivo, indicating that clinical resistance to biochemical mTOR inhibition was not cell-intrinsic. Rapamycin treatment led to Akt activation in seven patients, presumably due to loss of negative feedback, and this activation was associated with shorter time-to-progression during post-surgical maintenance rapamycin therapy (p < 0.05, Logrank test).
Conclusions
Rapamycin has anticancer activity in PTEN-deficient glioblastoma and warrants further clinical study alone or in combination with PI3K pathway inhibitors. The short-term treatment endpoints used in this neoadjuvant trial design identified the importance of monitoring target inhibition and negative feedback to guide future clinical development.
Trial registration: http://www.ClinicalTrials.gov (#NCT00047073).
In a Phase I clinical trial Charles Sawyers and colleagues investigated the role of rapamycin in patients with PTEN-deficient glioblastoma.
Editors' Summary
Background.
Glioblastoma is a highly malignant tumor of the brain. As with other tumors, it can result from a number of different molecular changes. Traditional chemotherapy does little more than contain these tumors, and cannot cure it. An alternative approach to the treatment of such tumors is to target specific molecular changes in the tumor. Obviously such targeted treatment will work only in patients who have the specific molecular defect being targeted. Hence, traditional clinical trials, which include a large variety of different patients and tumors with different genetic changes, may be an inappropriate way to test how effective targeted treatments are.
One specific change that has been identified in around 40% of patients with glioblastoma is inactivation of a gene known as PTEN, which acts as a tumor suppressor gene. When PTEN is inactivated it has previously been shown to make cells more sensitive to a class of drugs known as mTOR inhibitors—one of which is rapamycin (trade name Sirolimus). mTOR is a protein that is involved in the regulation of a number of cellular processes including growth and proliferation. Drugs active against mTOR are currently being tested for effectiveness against other cancers and as immunosuppressive agents.
Why Was This Study Done?
This was a Phase I study—that is, the earliest type of a drug study that is done in humans—which aimed to look at the safety of rapamycin in a selected group of patients who were undergoing surgery after recurrence of glioblastoma, and whose tumors did not express PTEN. In addition, the authors also wanted to assess the feasibility of incorporating detailed molecular studies of the action of this drug into such a Phase I study and whether these molecular studies could predict whether patients were more or less likely to respond to rapamycin.
What Did the Researchers Do and Find?
A total of 15 patients were treated with rapamycin at differing doses for one week before surgery and then again after surgery until there was evidence that the tumors were progressing. There was no evidence of very severe toxicity in any of the patients, though there were some adverse effects that required treatment. When samples from the patients were tested after surgery, seven of them showed a reduction in how rapidly the tumor cells divided, and this reduction was associated with how much inhibition there was of mTOR. Two of these patients showed evidence on scans of a reduction in tumor mass. Cells from tumors that appeared resistant to rapamycin in patients were sensitive to rapamycin in tissue culture, suggesting that the lack of response was due to the drug not being able to penetrate the tumor. A second, unfortunate effect of rapamycin was to cause activation of another intracellular protein, Akt, in some patients; when this activation occurred, patients had a shorter time between surgery and a return of their disease.
What Do These Findings Mean?
The detailed molecular studies within this Phase I trial allow a better understanding of how this targeted drug works. These findings suggest that the rapamycin can reduce the proliferation rate of glioblastoma cells, and that this reduction appears to be related to how well the drug is able to penetrate the tumor and inhibit mTOR. However, in some patients the activation of a second pathway can speed up the course of the disease, so further trials should incorporate inhibitors of this second pathway.
Additional Information.
Please access these Web sites via the online version of this summary at http://dx.doi.org/10.1371/journal.pmed.0050008.
The US National Cancer Institute provides information on all aspects of cancer (in English and Spanish)
The UK charity Cancerbackup provides information on brain tumors
Wikipedia has a page on mTOR (note that Wikipedia is a free online encyclopedia that anyone can edit; available in several languages)
doi:10.1371/journal.pmed.0050008
PMCID: PMC2211560  PMID: 18215105
19.  Thermal Ablation of Lung Tumors 
Lung cancer remains the leading cause of cancer death in the United States, accounting for an estimated 29% of cancer deaths in 2009.1 Pneumonectomy or lobectomy with hilar and mediastinal lymph node sampling is the gold standard treatment and offers the best option for cure of stage 1/2 nonsmall cell lung cancer (NSCLC).2 Unfortunately, only 15% of patients present with stage 1/2 disease, and many of these patients do not meet the pulmonary physiologic guidelines for lobar resection.3 In addition to lung cancer, pulmonary metastases are present in 25% to 30% of patients dying from all types of cancer.4 For some patients with oligometastatic pulmonary disease, metastectomy is associated with an improvement in survival.5 External beam radiation traditionally has been offered as the alternative to surgical resection for NSCLC or pulmonary metastatic disease. Unfortunately, the 5-year survival following radiation for stage 1 and 2 NSCLC remains low at 15% to 20%, with local recurrence being the most common mode of failure.6,7 Thermal ablation offers an intriguing therapeutic option to increase local tumor control and survival in patients with early stage NSCLC or with limited metastatic disease from nonlung primaries who are not surgical candidates because of poor cardiopulmonary reserve, anatomic constraints limiting resection, failure of traditional therapies, or refusal of operative approaches.
Thermal ablation has been shown to be effective in treating tumors in bone, kidney, and liver.8–11 Most preclinical and clinical trials have focused on demonstrating the feasibility of three modalities for pulmonary thermal ablation, namely radiofrequency (RF) ablation, microwave (MW) ablation, and cryoablation. This article discusses the unique challenges of performing thermal ablation in lung tissue and reviews the current literature regarding RF, MW, and cryoablation in the lung.
doi:10.1016/j.soc.2010.11.008
PMCID: PMC3155988  PMID: 21377589
Ablation; Lung; Cancer; Thermal
20.  A Primary Xenograft Model of Small Cell Lung Cancer Reveals Irreversible Changes in Gene Expression Imposed by Culture In-Vitro 
Cancer research  2009;69(8):3364.
Traditional approaches to the preclinical investigation of cancer therapies rely on the use of established cell lines maintained in serum-based growth media. This is particularly true of small cell lung cancer (SCLC), where surgically resected tissue is rarely available. Recent attention has focused on the need for better models that preserve the integrity of cancer stem cell populations, as well as three-dimensional tumor-stromal interactions. Here we describe a primary xenograft model of SCLC in which endobronchial tumor specimens obtained from chemo-naive patients are serially propagated in vivo in immunodeficient mice. In parallel, cell lines grown in conventional tissue culture conditions were derived from each xenograft line, passaged for 6 months, and then re-implanted to generate secondary xenografts. Using the Affymetrix platform, we analyzed gene expression in primary xenograft, xenograft-derived cell line, and secondary xenograft, and compared these data to similar analyses of unrelated primary SCLC samples and laboratory models. When compared to normal lung, primary tumors, xenografts and cell lines displayed a gene expression signature specific for SCLC. Comparison of gene expression within the xenograft model identified a group of tumor-specific genes expressed in primary SCLC and xenografts that was lost during the transition to tissue culture, and that was not regained when the tumors were re-established as secondary xenografts. Such changes in gene expression may be a common feature of many cancer cell culture systems, with functional implications for the use of such models for preclinical drug development.
doi:10.1158/0008-5472.CAN-08-4210
PMCID: PMC2821899  PMID: 19351829
Lung; Cancer; Xenograft; Expression; Microarray
21.  Emerging drug discovery approaches for selective targeting of “precursor” metastatic breast cancer cells: highlights and perspectives 
Breast cancer is a prevalent disease and a major cause of morbidity and cancer-related deaths among women worldwide. A significant number of patients at the time of primary diagnosis present metastatic disease, at least to locoregional lymph nodes, which results in somewhat unpredictable prognosis that often prompts adjuvant systemic therapies of various kinds. The time course of distant recurrence is also unpredictable with some patients sustaining a recurrence within months after diagnosis, even during adjuvant treatments, while others can experience recurrence years or decades after initial diagnosis. To date, clinically approved therapeutics yielded marginal benefits for patients with systemic metastatic breast disease, since despite high clinical responses to various therapies, the patients virtually always become resistant and tumor relapses. Molecular profiling studies established that breast cancer is highly heterogeneous and encompasses diverse histological and molecular subtypes with distinct biological and clinical implications in particular in relation to the incidence of progression to metastasis. The latter has been recognized to result from late genetic events during the multistep progression proposed by the dominant theory of carcinogenesis. However, there is evidence that the dissemination of primary cancer can also be initiated at a very early stage of cancer development, originating from rare cell variants, possibly cancer stem-like cells (CSC), with invasive potential. These precursor metastatic cancer cells with stem-like properties are defined by their ability to self-renew and to regenerate cell variants, which have high plasticity and intrinsic invasive properties required for dissemination and tropism toward specific organs. Equally relevant to the CSC hypothesis for metastasis formation is the epithelial-mesenchymal transition (EMT) process, which is critical for the acquisition of cancer cell invasive behavior and for selection/gain of CSC properties. These exciting concepts have led to the formulation of various approaches for targeting precursor metastatic cells, and these have taken on greater priority in therapeutic drug discovery research by both academia and pharmaceuticals. In this review, we focus on current efforts in medicinal chemistry to develop small molecules able to target precursor metastatic cells via interference with the CSC/EMT differentiation program, self-renewal, and survival. It is not meant to be comprehensive and the reader is referred to selected reviews that provide coverage of related basic aspects. Rather, emphasis is given to promising molecules with CSC/EMT signaling at the preclinical stage and in clinical trials that are paving the way to new generations of anti-metastasis drugs.
PMCID: PMC3204890  PMID: 22046485
Breast cancer; metastasis; cancer stem cells; EMT; experimental therapy
22.  A Six-Gene Signature Predicts Survival of Patients with Localized Pancreatic Ductal Adenocarcinoma 
PLoS Medicine  2010;7(7):e1000307.
Jen Jen Yeh and colleagues developed and validated a six-gene signature in patients with pancreatic ductal adenocarcinoma that may be used to better stage the disease in these patients and assist in treatment decisions.
Background
Pancreatic ductal adenocarcinoma (PDAC) remains a lethal disease. For patients with localized PDAC, surgery is the best option, but with a median survival of less than 2 years and a difficult and prolonged postoperative course for most, there is an urgent need to better identify patients who have the most aggressive disease.
Methods and Findings
We analyzed the gene expression profiles of primary tumors from patients with localized compared to metastatic disease and identified a six-gene signature associated with metastatic disease. We evaluated the prognostic potential of this signature in a training set of 34 patients with localized and resected PDAC and selected a cut-point associated with outcome using X-tile. We then applied this cut-point to an independent test set of 67 patients with localized and resected PDAC and found that our signature was independently predictive of survival and superior to established clinical prognostic factors such as grade, tumor size, and nodal status, with a hazard ratio of 4.1 (95% confidence interval [CI] 1.7–10.0). Patients defined to be high-risk patients by the six-gene signature had a 1-year survival rate of 55% compared to 91% in the low-risk group.
Conclusions
Our six-gene signature may be used to better stage PDAC patients and assist in the difficult treatment decisions of surgery and to select patients whose tumor biology may benefit most from neoadjuvant therapy. The use of this six-gene signature should be investigated in prospective patient cohorts, and if confirmed, in future PDAC clinical trials, its potential as a biomarker should be investigated. Genes in this signature, or the pathways that they fall into, may represent new therapeutic targets.
Please see later in the article for the Editors' Summary
Editors' Summary
Background
Pancreatic cancer kills nearly a quarter of a million people every year. It begins when a cell in the pancreas (an organ lying behind the stomach that produces digestive enzymes and hormones such as insulin, which controls blood sugar levels) acquires genetic changes that allow it to grow uncontrollably and to spread around the body (metastasize). Nearly all pancreatic cancers are “pancreatic ductal adenocarcinomas” (PDACs)—tumors that start in the cells that line the tubes in the pancreas that take digestive juices to the gut. Because PDAC rarely causes any symptoms early in its development, it has already metastasized in about half of patients before it is diagnosed. Consequently, the average survival time after a diagnosis of PDAC is only 5–8 months. At present, the only chance for cure is surgical removal (resection) of the tumor, part of the pancreas, and other nearby digestive organs. The operation that is needed for the majority of patients—the Whipple procedure—is only possible in the fifth of patients whose tumor is found when it is small enough to be resectable but even with postoperative chemotherapy, these patients only live for 23 months after surgery on average, possibly because they have micrometastases at the time of their operation.
Why Was This Study Done?
Despite this poor overall outcome, about a quarter of patients with resectable PDAC survive for more than 5 years after surgery. Might some patients, therefore, have a less aggressive form of PDAC determined by the biology of the primary (original) tumor? If this is the case, it would be useful to be able to stratify patients according to the aggressiveness of their disease so that patients with very aggressive disease could be given chemotherapy before surgery (neoadjuvant therapy) to kill any micrometastases. At present neoadjuvant therapy is given to patients with locally advanced, unresectable tumors. In this study, the researchers compare gene expression patterns in primary tumor samples collected from patients with localized PDAC and from patients with metastatic PDAC between 1999 and 2007 to try to identify molecular markers that distinguish between more and less aggressive PDACs.
What Did the Researchers Do and Find?
The researchers identified a six-gene signature that was associated with metastatic disease using a molecular biology approach called microarray hybridization and a statistical method called significance analysis of microarrays to analyze gene expression patterns in primary tumor samples from 15 patients with localized PDAC and 15 patients with metastatic disease. Next, they used a training set of tumor samples from another 34 patients with localized and resected PDAC, microarray hybridization, and a graphical method called X-tile to select a combination of expression levels of the six genes that discriminated optimally between high-risk (aggressive) and low-risk (less aggressive) tumors on the basis of patient survival (a “cut-point”). When the researchers applied this cut-point to an independent set of 67 tumor samples from patients with localized and resected PDAC, they found that 42 patients had high-risk tumors. These patients had an average survival time of 15 months; 55% of them were alive a year after surgery. The remaining 25 patients, who had low-risk tumors, had an average survival time of 49 months and 91% of them were alive a year after resection.
What Do These Findings Mean?
These and other findings identify a six-gene signature that can predict outcomes in patients with localized, resectable PDAC better than, and independently of, established clinical markers of outcome. If the predictive ability of this signature can be confirmed in additional patients, it could be used to help patients make decisions about their treatment. For example, a patient wondering whether to risk the Whipple procedure (2%–6% of patients die during this operation and more than 50% have serious postoperative complications), the knowledge that their tumor was low risk might help them decide to have the operation. Conversely, a patient in poor health with a high-risk tumor might decide to spare themselves the trauma of major surgery. The six-gene signature might also help clinicians decide which patients would benefit most from neoadjuvant therapy. Finally, the genes in this signature, or the biological pathways in which they participate, might represent new therapeutic targets for the treatment of PDAC.
Additional Information
Please access these Web sites via the online version of this summary at http://dx.doi.org/10.1371/journal.pmed.1000307.
The US National Cancer Institute provides information for patients and health professionals about all aspects of pancreatic cancer (in English and Spanish), including a booklet for patients
The American Cancer Society also provides detailed information about pancreatic cancer
The UK National Health Service and Cancer Research UK include information for patients on pancreatic cancer on their Web sites
MedlinePlus provides links to further resources on pancreatic cancer (in English and Spanish)
Cure Pancreatic Cancer provides information about scientific and medical research related to the diagnosis, treatment, cure, and prevention of pancreatic cancer
Pancreatic Cancer Action Network is a US organization that supports research, patient support, community outreach, and advocacy for a cure for pancreatic cancer
doi:10.1371/journal.pmed.1000307
PMCID: PMC2903589  PMID: 20644708
23.  Fibroblast growth factor receptor splice variants are stable markers of oncogenic transforming growth factor β1 signaling in metastatic breast cancers 
Introduction
Epithelial–mesenchymal transition (EMT) and mesenchymal–epithelial transition (MET) facilitate breast cancer (BC) metastasis; however, stable molecular changes that result as a consequence of these processes remain poorly defined. Therefore, with the hope of targeting unique aspects of metastatic tumor outgrowth, we sought to identify molecular markers that could identify tumor cells that had completed the EMT:MET cycle.
Methods
An in vivo reporter system for epithelial cadherin (E-cad) expression was used to quantify its regulation in metastatic BC cells during primary and metastatic tumor growth. Exogenous addition of transforming growth factor β1 (TGF-β1) was used to induce EMT in an in situ model of BC. Microarray analysis was employed to examine gene expression changes in cells chronically treated with and withdrawn from TGF-β1, thus completing one full EMT:MET cycle. Changes in fibroblast growth factor receptor type 1 (FGFR1) isoform expression were validated using PCR analyses of patient-derived tumor tissues versus matched normal tissues. FGFR1 gene expression was manipulated using short hairpin RNA depletion and cDNA rescue. Preclinical pharmacological inhibition of FGFR kinase was employed using the orally available compound BGJ-398.
Results
Metastatic BC cells undergo spontaneous downregulation of E-cad during primary tumor growth, and its expression subsequently returns following initiation of metastatic outgrowth. Exogenous exposure to TGF-β1 was sufficient to drive the metastasis of an otherwise in situ model of BC and was similarly associated with a depletion and return of E-cad expression during metastatic progression. BC cells treated and withdrawn from TGF-β stably upregulate a truncated FGFR1-β splice variant that lacks the outermost extracellular immunoglobulin domain. Identification of this FGFR1 splice variant was verified in metastatic human BC cell lines and patient-derived tumor samples. Expression of FGFR1-β was also dominant in a model of metastatic outgrowth where depletion of FGFR1 and pharmacologic inhibition of FGFR kinase activity both inhibited pulmonary tumor outgrowth. Highlighting the dichotomous nature of FGFR splice variants and recombinant expression of full-length FGFR1-α also blocked pulmonary tumor outgrowth.
Conclusion
The results of our study strongly suggest that FGFR1-β is required for the pulmonary outgrowth of metastatic BC. Moreover, FGFR1 isoform expression can be used as a predictive biomarker for therapeutic application of its kinase inhibitors.
doi:10.1186/bcr3623
PMCID: PMC4053226  PMID: 24618085
24.  Pfetin as a Risk Factor of Recurrence in Gastrointestinal Stromal Tumors 
BioMed Research International  2014;2014:651935.
Background. Despite complete resection of gastrointestinal stromal tumors (GIST), recurrent and/or metastatic disease occurs, often depending on the grade of malignancy. As such, markers are needed that accurately predict patients at high risk for recurrence. Previously our group reported Pfetin as a prognostic biomarker for GIST. In order to create an approach for predicting risk of recurrence, we incorporated Pfetin expression with clinicopathological data to produce a predictive model. Object. Forty-five patients with localized primary GIST were treated with complete gross surgical resection surgically at our institution between 1995 and 2010 were included. The majority of tumors originated in the stomach (38 cases), as well as small intestine (6 cases) and rectum (1 case). Method. (1) We performed retrospective analysis of the connection between Pfetin expression, clinicopathological data, and incidences of recurrence, using bivariate and multivariate analyses. (2) The reactivity of the monoclonal antibody against Pfetin was examined by immunohistochemistry. Pfetin. We have reported Pfetin, identified microarray technology, and compared between statistically different GISTs for good and poor prognoses and for prognostic marker. Results. There were 7 cases of recurrences. (1) By univariate analysis, tumor size, mitoses, exposure to abdominal cavity, and complete tumor removal predicted risk of recurrence. (2) Pfetin-negative cases were significantly related to recurrence (P = 0.002). Conclusions. This analysis demonstrates that lack of Pfetin expression is an additional predictor of recurrence in resected GIST. Further study may determine the role of this variable added to the current predictive model for selection of adjuvant therapy.
doi:10.1155/2014/651935
PMCID: PMC4055574  PMID: 24977158
25.  The prognostic value of ERCC1 and RRM1 gene expression in completely resected non-small cell lung cancer: tumor recurrence and overall survival 
Background
The roles of excision repair cross-complementing group 1 gene (ERCC1) expression and ribonucleotide reductase subunit M1 gene (RRM1) expression in completely resected non-small cell lung cancer (NSCLC) are still debatable. Previous studies have shown that both genes affected the overall survival and outcomes of patients who received platinum-based chemotherapy; however, some studies did not show this correlation. The aim of this study was to evaluate the prognostic values of ERCC1 and RRM1 gene expression in predicting tumor recurrence and overall survival in patients with completely resected NSCLC who received adjuvant chemotherapy and in those who did not.
Patients and methods
A retrospective cohort study was conducted in 247 patients with completely resected NSCLC. All patients had been treated with anatomic resection (lobectomy or pneumonectomy) with systematic mediastinal lymphadenectomy between January 2002 and December 2011 at Chiang Mai University Hospital, Chiang Mai, Thailand. They were divided into two groups: recurrence and no recurrence. Protein expression of ERCC1 and RRM1 was determined by immunohistochemistry. Correlations between clinicopathologic variables, including ERCC1 and RRM1 expression and tumor recurrence, were analyzed. Univariate and multivariate Cox proportional hazards regression analysis stratified by nodal involvement, tumor staging, intratumoral blood vessel invasion, intratumoral lymphatic invasion, and tumor necrosis was used to identify the prognostic roles of ERCC1 and RRM1.
Results
ERCC1 and RRM1 expression did not demonstrate prognostic value for tumor recurrence and overall survival in patients with completely resected NSCLC. In patients who did not receive adjuvant chemotherapy treatment, those with high ERCC1 and high RRM1 expression seemed to have greater potential for tumor recurrence and shorter overall survival than did those who had low ERCC1 and low RRM1 (hazard ratio [HR] =1.7, 95% confidence interval [CI] =0.6–4.3, P=0.292 and HR =1.6, 95% CI =0.5–4.5, P=0.411, respectively). In contrast, in patients who received adjuvant chemotherapy treatment, those with high ERCC1 and high RRM1 expression seemed to have benefited from adjuvant chemotherapy and showed good overall survival compared with those who had low ERCC1 and low RRM1 (HR =0.8, 95% CI = 0.4–1.8, P=0.612 and HR = 0.4, 95% CI = 0.1–2.4, P=0.325, respectively). Subgroup analysis in patients whose first-line metastatic chemotherapy failed demonstrated that ERCC1 expression and RRM1 expression were not prognostic factors for tumor recurrence and overall survival; however, patients who had high ERCC1 and high RRM1 expression seemed to have benefited from first-line chemotherapy treatment (HR =0.7, 95% CI =0.3–1.8, P=0.458).
Conclusion
ERCC1 expression and RRM1 expression were not prognostic of tumor recurrence and overall survival in patients with completely resected NSCLC, either with or without adjuvant chemotherapy. Prospective studies that include a larger number of patients are needed for definite conclusions.
doi:10.2147/CMAR.S52073
PMCID: PMC3794893  PMID: 24124391
ERCC1; RRM1; tumor recurrence; prognostic factor; NSCLC

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