We assessed the efficacy of Seneca Valley virus (SVV-001), a neuroendocrine cancer-selective oncolytic picornavirus, in primary heterotransplant mouse models of small cell lung cancer (SCLC), including three lines each of classic and variant SCLC. Half-maximal effective concentrations for cell lines derived from three variant heterotransplants ranged from 1.6×10–3 (95% confidence interval [CI] = 1×10–3 to 2.5×10–3) to 3.9×10–3 (95% CI = 2.8×10–3 to 5.5×10–3). Sustained tumor growth inhibition in vivo was only observed in variant lines (two-sided Student t test, P < .005 for each). Doses of 1014 vp/kg were able to completely and durably eradicate tumors in a variant SCLC heterotransplant model in two of six mice. Gene expression profiling revealed that permissive lines are typified by lower expression of the early neurogenic transcription factor ASCL1 and, conversely, by higher expression of the late neurogenic transcription factor NEUROD1. This classifier demonstrates a sensitivity of .89, specificity of .92, and accuracy of .91. The NEUROD1 to ASCL1 ratio may serve as a predictive biomarker of SVV-001 efficacy.
A diagnosis of small cell lung cancer (SCLC) today confers essentially the same terrible prognosis that it did 25 years ago, when common use of cisplatin-based chemotherapy began for this disease. In contrast to past decades of research on many other solid tumors, studies of combination chemotherapy using later generation cytotoxics and targeted kinase inhibitors have not had a significant impact on standard care for SCLC. The past few years have seen suggestions of incrementally improved outcomes using standard cytotoxics, including cisplatin-based combination studies of irinotecan and amrubicin by Japanese research consortia. Confirmatory phase III studies of these agents are ongoing in the United States. Antiangiogenic strategies are also of primary interest and are in late-phase testing. Several novel therapeutics, including high-potency small molecule inhibitors of Bcl-2 and the Hedgehog signaling pathway, and a recently discovered replication-competent picornavirus, have shown remarkable activity against SCLC in preclinical models and are currently in simultaneous phase I clinical development. Novel therapeutic approaches based on advances in understanding of the biology of SCLC have the potential to radically change the outlook for patients with this disease.
Small cell lung cancer; novel therapeutics; Bcl-2; Hedgehog; SVV-001
New therapies are critically needed to improve the outcome for patients with small cell lung cancer (SCLC). IGF-1R inhibition is a potential treatment strategy for SCLC: the IGF-1R pathway is commonly upregulated in SCLC, and has been associated with inhibition of apoptosis and stimulation of proliferation through downstream signaling pathways including PI3K-Akt and MAPK. To evaluate potential determinants of response to IGF-1R inhibition, we assessed the relative sensitivity of 19 SCLC cell lines to OSI-906, a small molecule inhibitor of IGF-1R and the closely related insulin receptor (IR). Approximately one third of these cell lines were sensitive to OSI-906, with an IC50 < 1 μM. Cell line expression of IGF-1R, IR, IGF-1, IGF-2, IGFBP3, and IGFBP6 did not correlate with sensitivity to OSI-906. Interestingly, OSI-906 sensitive lines expressed significantly lower levels of baseline phospho-ERK relative to resistant lines (p=0.006). OSI-906 treatment resulted in dose-dependent inhibition of phospho-IGF-1R and phospho-Akt in both sensitive and resistant cell lines, but induced apoptosis and cell cycle arrest only in sensitive lines. We tested the in vivo efficacy of OSI-906 using an NCI-H187 xenograft model and two SCLC patient xenografts in mice. OSI-906 treatment resulted in 50% tumor growth inhibition in NCI-H187 and 30% inhibition in the primary patient xenograft models compared to mock treated animals. Taken together our data support IGF-1R inhibition as a viable treatment strategy for a defined subset of SCLC and suggest that low pretreatment levels of phospho-ERK may be indicative of sensitivity to this therapeutic approach.
IGF-1R; ERK; AKT; primary xenograft; small cell lung cancer
Preclinical studies suggested that the oral anti-fungal agent itraconazole specifically inhibits proliferation, migration, and tube formation of endothelial cells. Itraconazole has potent anti-angiogenic activity and enhances the efficacy of cytotoxic chemotherapy in multiple primary xenograft lung cancer models. Based on these data, we performed an exploratory clinical study assessing the efficacy of itraconazole with cytotoxic chemotherapy in the treatment of patients with advanced lung cancer.
The study enrolled patients with progressive non-squamous non-small cell lung cancer after one prior cytotoxic therapy for metastatic disease, randomized 2:1 to pemetrexed 500 mg/m2 IV day 1 with or without itraconazole 200 mg oral daily on a 21-day cycle. Outcome measures included percent progression-free at 3 months, progression-free survival, overall survival, and observed toxicity.
A total of 23 patients were enrolled; the study was stopped early due to increasing use of pemetrexed in the first line setting. Sixty-seven percent of patients were progression-free at 3 months on itraconazole plus pemetrexed vs. 29% on the control arm of pemetrexed alone (p=0.11). Median progression-free survivals were 5.5 months (itraconazole) vs. 2.8 months (control) (hazard ratio (HR)=0.399, p=0.089). Overall survival was longer in patients receiving itraconazole (median 32 months) vs. control (8 months) (HR=0.194, p=0.012). There were no evident differences in toxicity between the study arms.
Itraconazole is well tolerated in combination with pemetrexed. Consistent with our preclinical data, daily itraconazole administration is associated with trends suggestive of improved disease control in patients receiving chemotherapy for advanced lung cancer.
Itraconazole; anti-angiogenic; lung cancer
A large fraction of non-small cell lung cancers (NSCLC) are dependent on defined oncogenic driver mutations. Although targeted agents exist for EGFR- and EML4-ALK-driven NSCLC, no therapies target the most frequently found driver mutation, KRAS. Furthermore, acquired resistance to the currently targetable driver mutations is nearly universally observed. Clearly a novel therapeutic approach is needed to target oncogene driven NSCLC. We recently demonstrated that the basic helix-loop-helix transcription factor Twist1 cooperates with mutant Kras to induce lung adenocarcinoma in transgenic mouse models and that inhibition of Twist1 in these models led to Kras-induced senescence. In the current study, we examine the role of TWIST1 in oncogene driven human NSCLC. Silencing of TWIST1 in KRAS mutant human NSCLC cell lines resulted in dramatic growth inhibition and either activation of a latent oncogene-induced senescence program or in some cases, apoptosis. Similar effects were observed in EGFR mutation driven and c-Met amplified NSCLC cell lines. Growth inhibition by silencing of TWIST1 was independent of p53 or p16 mutational status and did not require previously defined mediators of senescence, p21 and p27, nor could this phenotype be rescued by overexpression of SKP2. In xenograft models, silencing of TWIST1 resulted in significant growth inhibition of KRAS mutant, EGFR mutant and c-Met amplified NSCLC. Remarkably, inducible silencing of TWIST1 resulted in significant growth inhibition of established KRAS mutant tumors. Together these findings suggest that silencing of TWIST1 in oncogene driver dependent NSCLC represents a novel and promising therapeutic strategy.
TWIST1; OIS; KRAS; NSCLC; EGFR
Recognition of the multiple roles of Hedgehog signaling in cancer has prompted intensive efforts to develop targeted pathway inhibitors. Leading inhibitors in clinical development act by binding to a common site within Smoothened, a critical pathway component. Acquired Smoothened mutations, including SMOD477G, confer resistance to these inhibitors. We report here that itraconazole and arsenic trioxide, two agents in clinical use that inhibit Hedgehog signaling by mechanisms distinct from that of current Smoothened antagonists, retain inhibitory activity in vitro in the context of all reported resistance-conferring Smoothened mutants and GLI2 overexpression. Itraconazole and arsenic trioxide, alone or in combination, inhibit the growth of medulloblastoma and basal cell carcinoma in vivo, and prolong survival of mice with intracranial drug-resistant SMOD477G medulloblastoma.
Small cell lung cancer (SCLC) is an aggressive disease with one of the highest case-fatality rates among cancer. The recommended therapy for SCLC has not changed significantly over the past 30 years; new therapeutic approaches are a critical need. TP53 is mutated in the majority of SCLC cases and its loss is required in transgenic mouse models of the disease. We synthesized an array of biodegradable poly(beta-amino ester) (PBAE) polymers which self-assemble with DNA and assayed for transfection efficiency in the p53-mutant H446 SCLC cell line using high-throughput methodologies. Two of the top candidates were selected for further characterization and TP53 delivery in vitro and in vivo. Nanoparticle delivery of TP53 resulted in expression of exogenous p53, induction of p21, induction of apoptosis and accumulation of cells in sub-G1 consistent with functional p53 activity. Intratumoral injection of subcutaneous H446 xenografts with polymers carrying TP53 caused marked tumor growth inhibition. This is the first demonstration of TP53 gene therapy in SCLC using non-viral polymeric nanoparticles. This technology may have general applicability as a novel anti-cancer strategy based on restoration of tumor suppressor gene function.
p53; PBAE; nanoparticles; gene therapy; SCLC
Among the cellular responses observed following treatment with DNA-damaging agents is the activation of Short Interspersed Elements (SINEs; retrotransposable genetic elements that comprise over 10% of the human genome). By placing a human SINE (the Alu element) into murine cells, we have previously shown that DNA-damaging agents such as etoposide can induce both upregulation of SINE transcript levels and SINE retrotransposition. A similarly cytotoxic (but not genotoxic) exposure to vincristine was not associated with SINE activation. Here we demonstrate that multiple other genotoxic exposures are associated with upregulation of SINE transcript levels. By comparing the effects of similarly cytotoxic doses of the topoisomerase II inhibitors etoposide and merbarone, we confirm that DNA strand breakage is specifically associated with SINE induction. By evaluating transcription rate and RNA stability, we demonstrate that SINE induction by genotoxic exposure is associated with transcriptional induction and not with transcript stabilization. Finally we demonstrate that SINE induction by genotoxic stress is mediated by a Trp53-independent pathway, and in fact that Trp53 plays an inhibitory role in attenuating the transcriptional induction of SINE elements following exposure to a genotoxic agent. Together these data support a model in which initial DNA damage can trigger genomic instability due to SINE activation, a response which may be amplified in cancer cells lacking functional TP53.
Bcl-2 is a critical regulator of apoptosis that is overexpressed in the majority of small cell lung cancers (SCLC). Nativoclax (ABT-263) is a potent and selective inhibitor of Bcl-2 and Bcl-xL. The primary objectives of this phase IIa study included safety at the recommended phase II dose and preliminary, exploratory efficacy assessment in patients with recurrent and progressive SCLC after at least one prior therapy.
Thirty-nine patients received navitoclax 325 mg daily, following an initial lead-in of 150 mg daily for 7 days. Study endpoints included safety and toxicity assessment, response rate, progression-free and overall survival (PFS and OS), as well as exploratory pharmacodynamic correlates.
The most common toxicity associated with navitoclax was thrombocytopenia, which reached grade III–IV in 41% of patients. Partial response was observed in one (2.6%) patient and stable disease in 9 (23%) patients. Median PFS was 1.5 months and median OS was 3.2 months. A strong association between plasma pro–gastrin-releasing peptide (pro-GRP) level and tumor Bcl-2 copy number (R = 0.93) was confirmed. Exploratory analyses revealed baseline levels of cytokeratin 19 fragment antigen 21-1, neuron-specific enolase, pro-GRP, and circulating tumor cell number as correlates of clinical benefit.
Bcl-2 targeting by navitoclax shows limited single-agent activity against advanced and recurrent SCLC. Correlative analyses suggest several putative biomarkers of clinical benefit. Preclinical models support that navitoclax may enhance sensitivity of SCLC and other solid tumors to standard cytotoxics. Future studies will focus on combination therapies.
Vismodegib (GDC-0449), an orally bioavailable small-molecule inhibitor of Hedgehog signaling, was recently approved by the U.S. Food and Drug Administration for the treatment of basal cell carcinoma that is either metastatic or locally advanced in patients who are not candidates for surgical resection or radiation. Given the absence of previously defined effective drug therapy for this disease, approval was granted primarily on the basis of outcome of a nonrandomized parallel cohort phase II study of 99 patients with advanced basal cell carcinoma, with a primary endpoint of objective response rate. Response rates of 30.3% and 42.9% were observed in metastatic and locally advanced cohorts in this study, respectively, associated with median progression-free survival in both cohorts of 9.5 months. Ongoing clinical investigations include evaluation of the potential efficacy of vismodegib in a variety of diseases and in combination with other agents. The mechanism of action, preclinical and clinical data, and potential utility in other disease contexts are reviewed here.
Cancer patients at Johns Hopkins undergo insurance clearance to verify coverage for enrollment to interventional clinical trials. We sought to explore the impact of insurance clearance on disparities in access to cancer clinical trials at this urban comprehensive cancer center.
We evaluated the frequency of insurance-based denial of access to cancer clinical trials over a 5-year period after initiation of a formal insurance clearance process. We used a case-control design to compare demographic and clinical parameters of patients denied or approved for clinical trials participation by their insurance company in a 3-year interval.
From July 2003 to July 2008, insurance requests for clinical trial participation were submitted on 4,617 consented cancer patients at Johns Hopkins. A total of 628 patients (13.6%) with health insurance were denied therapeutic trial enrollment owing to lack of insurance coverage for participation. A total of 254 patients denied enrollment from 2005 to 2007 were selected for further analysis. Two-hundred sixty randomly selected patients approved for clinical trial participation served as controls. Patients approved were on average older (59.2 versus 54.9 years) than patients denied (P = 0.0001). Residents of Pennsylvania, which lacks a state law mandating cancer clinical trial coverage for residents, were overrepresented among the denied patients (P = 0.0009). No statistically significant variance in the likelihood of insurance denial was found on the basis of sex, race, stage of disease, or presence of comorbidities.
Denial of access to therapeutic clinical trials, even among insured patients, is a significant barrier to clinical cancer research. This barrier spans racial, ethnic, and gender categories.
The causative association between tobacco use and lung cancer is a well-established fact. However, lung cancer also occurs, at surprisingly high rates, in lifelong never smokers. In fact, lung cancer in never smokers is among the leading causes of cancer-related mortality. This CCR Focus summarizes recent data, identifies knowledge deficits, and suggests future research directions with regard to this critically important subset of lung cancer patients.
Vismodegib (GDC-0449), an orally bioavailable small molecule inhibitor of Hedgehog signaling, was recently approved by the U.S. Food and Drug Administration for the treatment of basal cell carcinoma that is either metastatic or locally advanced in patients who are not candidates for surgical resection or radiation. Given the absence of previously defined effective drug therapy for this disease, approval was granted based primarily on outcome of a non-randomized parallel cohort phase II study of 99 patients with advanced basal cell carcinoma, with a primary endpoint of objective response rate. Response rates of 30.3 and 42.9 percent were observed in metastatic and locally advanced cohorts in this study, respectively, associated with median progression-free survival in both cohorts of 9.5 months. Ongoing clinical investigations include evaluation of the potential efficacy of vismodegib in a variety of disease contexts, and in combination with other agents. The mechanism of action, preclinical and clinical data, and potential utility in other disease contexts are reviewed.
We sought to determine the frequency and clinical characteristics of patients with lung cancer harboring NRAS mutations. We used preclinical models to identify targeted therapies likely to be of benefit against NRAS mutant lung cancer cells.
Patients and Methods
We reviewed clinical data from patients whose lung cancers were identified at 6 institutions or reported in the Catalogue of Somatic Mutations in Cancer (COSMIC) to harbor NRAS mutations. 6 NRAS mutant cell lines were screened for sensitivity against inhibitors of multiple kinases (i.e. EGFR, ALK, MET, IGF-1R, BRAF, PI3K and MEK).
Among 4562 patients with lung cancers tested, NRAS mutations were present in 30 (0.7%; 95% confidence interval, 0.45% to 0.94%); 28 of these had no other driver mutations. 83% had adenocarcinoma histology with no significant differences in gender. While 95% of patients were former or current smokers, smoking-related G:C>T:A transversions were significantly less frequent in NRAS mutated lung tumors compared to KRAS-mutant NSCLCs (NRAS: 13% (4/30), KRAS: 66% (1772/2733), p<0.00000001). 5 of 6 NRAS mutant cell lines were sensitive to the MEK inhibitors, selumetinib and trametinib, but not to other inhibitors tested.
NRAS mutations define a distinct subset of lung cancers (~1%) with potential sensitivity to MEK inhibitors. While NRAS mutations are more common in current/former smokers, the types of mutations are not those classically associated with smoking.
NRAS mutation; EGFR mutation; KRAS mutation; lung cancer; non-small cell lung cancer; driver mutation; MEK inhibitor; erlotinib; gefitinib; crizotinib
Innovative therapies are needed for advanced Non-Small Cell Lung Cancer (NSCLC). We have undertaken a genomics based, hypothesis driving, approach to query an emerging potential that epigenetic therapy may sensitize to immune checkpoint therapy targeting PD-L1/PD-1 interaction. NSCLC cell lines were treated with the DNA hypomethylating agent azacytidine (AZA – Vidaza) and genes and pathways altered were mapped by genome-wide expression and DNA methylation analyses. AZA-induced pathways were analyzed in The Cancer Genome Atlas (TCGA) project by mapping the derived gene signatures in hundreds of lung adeno (LUAD) and squamous cell carcinoma (LUSC) samples. AZA up-regulates genes and pathways related to both innate and adaptive immunity and genes related to immune evasion in a several NSCLC lines. DNA hypermethylation and low expression of IRF7, an interferon transcription factor, tracks with this signature particularly in LUSC. In concert with these events, AZA up-regulates PD-L1 transcripts and protein, a key ligand-mediator of immune tolerance. Analysis of TCGA samples demonstrates that a significant proportion of primary NSCLC have low expression of AZA-induced immune genes, including PD-L1. We hypothesize that epigenetic therapy combined with blockade of immune checkpoints – in particular the PD-1/PD-L1 pathway – may augment response of NSCLC by shifting the balance between immune activation and immune inhibition, particularly in a subset of NSCLC with low expression of these pathways. Our studies define a biomarker strategy for response in a recently initiated trial to examine the potential of epigenetic therapy to sensitize patients with NSCLC to PD-1 immune checkpoint blockade.
Non-Small Cell Lung Cancer(NSCLC); Azacytidine; HDAC inhibitor
Lung cancer is mainly caused by smoking, but the quantitative relations between smoking and histologic subtypes of lung cancer remain inconclusive. Using one of the largest lung cancer datasets ever assembled, we explored the impact of smoking on risks of the major cell types of lung cancer. This pooled analysis included 13,169 cases and 16,010 controls from Europe and Canada. Studies with population controls comprised 66.5% of the subjects. Adenocarcinoma (AdCa) was the most prevalent subtype in never smokers and in women. Squamous cell carcinoma (SqCC) predominated in male smokers. Age-adjusted odds ratios (ORs) were estimated with logistic regression. ORs were elevated for all metrics of exposure to cigarette smoke and were higher for SqCC and small cell lung cancer (SCLC) than for AdCa. Current male smokers with an average daily dose of >30 cigarettes had ORs of 103.5 (95% CI 74.8-143.2) for SqCC, 111.3 (95% CI 69.8-177.5) for SCLC, and 21.9 (95% CI 16.6-29.0) for AdCa. In women, the corresponding ORs were 62.7 (95% CI 31.5-124.6), 108.6 (95% CI 50.7-232.8), and 16.8 (95% CI 9.2-30.6), respectively. Whereas ORs started to decline soon after quitting, they did not fully return to the baseline risk of never smokers even 35 years after cessation. The major result that smoking exerted a steeper risk gradient on SqCC and SCLC than on AdCa is in line with previous population data and biological understanding of lung cancer development.
cigarette smoking; lung cancer; relative risk characterization; tobacco smoke; stem cells
SCLC; tyrosine receptor kinases; developmental pathways; immunology; oncolytic replication-selective viruses
Epigenetic alterations are strongly associated with cancer development. We conducted a phase I/II trial of combined epigenetic therapy with azacitidine and entinostat, inhibitors of DNA methylation and histone deacetylation, respectively, in extensively pretreated patients with recurrent metastatic non-small cell lung cancer. This therapy is well tolerated, and objective responses were observed, including a complete response and a partial response in a patient who remains alive and without disease progression approximately 2 years after completing protocol therapy. Median survival in the entire cohort was 6.4 months (95% CI: 3.8–9.2), comparing favorably with existing therapeutic options. Demethylation of a set of four epigenetically silenced genes known to be associated with lung cancer was detectable in serial blood samples in these patients, and was associated with improved progression-free (p=0.034) and overall survival (p=0.035). Four of 19 patients had major objective responses to subsequent anti-cancer therapies given immediately following epigenetic therapy.
azacitidine; entinostat; demethylation; histone deacetylase inhibitor
The Notch signaling pathway is a critical embryonic developmental regulatory pathway that has been implicated in oncogenesis. In non-small cell lung cancer (NSCLC), recent evidence suggests that Notch signaling may contribute to maintenance of a cancer stem or progenitor cell compartment required for tumorigenesis. We explored whether intact Notch signaling is required for NSCLC clonogenic and tumorigenic potential in vitro and in vivo using a series of genetically modified model systems. In keeping with previous observations, we find that Notch3 in particular is upregulated in human lung cancer lines, and that down regulation of Notch signaling using a selective γ-secretase inhibitor (MRK-003) is associated with decreased proliferation and clonogenic capacity in vitro. We demonstrate that this phenotype is rescued with the expression of NICD3, a constitutively active cleaved form of Notch3 not affected by γ-secretase inhibition. Using an inducible LSL-KRASG12D model of lung cancer in vivo, we demonstrate a transient upregulation of Notch pathway activity in early tumor precursor lesions. However, a more rigorous test of the requirement for Notch signaling in lung oncogenesis, crossing the LSL-KRASG12D mouse model with a transgenic with a similarly inducible global dominant negative suppressor of Notch activity, LSL-DNMAML (dominant negative mastermind-like), reveals no evidence of Notch pathway requirement for lung tumor initiation or growth in vivo. Distinct Notch family members may have different, and potentially opposing, activities in oncogenesis, and targeted inhibition of individual Notch family members may be a more effective anti-cancer strategy than global pathway suppression.
The aim of this study was to determine the maximum tolerated dose (MTD), dose limiting toxicities (DLTs), and determine the phase II dose for the combination of irinotecan-carboplatin-paclitaxel given as induction chemotherapy and with concomitant chest radiotherapy for patients with Stage III non-small cell lung cancer.
Patients with Cancer and Leukemia Group B performance status of 0 to 2, stage IIIA and IIIB NSCLC patients with resectable or unresectable disease were treated with induction chemotherapy (irinotecan 100 mg/m2, carboplatin AUC 5, and paclitaxel 175 mg/m2 days 1 and 22) followed by concomitant chemotherapy (irinotecan, carboplatin, and paclitaxel) and chest radiotherapy (66 Gy for unresectable and 50 Gy for resectable disease) beginning on week 7. The primary objective was to escalate the dose of irinotecan during chemoradiation in sequential cohorts to determine the DLT and MTD of the regimen.
Thirty-eight patients were enrolled (median age 63 years, 57% male, 41% performance status 0, 30% resectable). Induction chemotherapy was tolerable and active (response rate 26%; stable disease 60%). Eight patients did not receive concurrent chemoradiotherapy because of progressive disease (5), death (1), hypersensitivity reaction to paclitaxel (1), and withdrawal of consent (1). Twenty-nine patients received concurrent chemoradiotherapy. The concomitant administration of chest radiotherapy with weekly irinotecan, carboplatin, and paclitaxel was not feasible at the first, second, and third dose levels. DLT was failure to achieve recovery to ≤ grade 1 absolute neutrophil count by the day of scheduled chemotherapy administration. Dose de-escalation to irinotecan 30 mg/m2, paclitaxel 40 mg/m2 (with omission of carboplatin) delivered on weeks 2, 3, 5, and 6 of radiotherapy was the MTD. After induction chemotherapy, partial responses, stable disease, and progressive disease was observed in 26%, 60%, and 14% of patients, respectively. After chemoradiotherapy, partial responses were attained in 16 (55%) patients, whereas 12 patients (41%) attained disease stabilization. Median overall survival was 21 months for the entire cohort. Resectable patients had a median survival of 24 months, whereas unresectable patients had a median survival of 19 months. Differences in overall and progression-free survival rates between resectable and unresectable patients was not statistically significant (p = 0.52 and p = 0.90, respectively).
Carboplatin, paclitaxel, and irinotecan with concurrent chemoradiotherapy was poorly tolerated as a result of neutropenia. Although dose de-escalation was required for delivery of the regimen, the response rates and survival outcomes were comparable to other similar regimens.
Non-small cell lung cancer; Irinotecan; Radiation therapy; Multimodality therapy
The anti-angiogenic agent bevacizumab has been approved for the treatment of non-small cell lung cancer, although the survival benefit associated with this agent is marginal, and toxicities and cost are substantial. A recent screen for selective inhibitors of endothelial cell proliferation identified the oral anti-fungal drug itraconazole as a novel agent with potential anti-angiogenic activity. Here we define and characterize the anti-angiogenic and anti-cancer activities of itraconazole in relevant preclinical models of angiogenesis and lung cancer. Itraconazole consistently demonstrated potent, specific, and dose-dependent inhibition of endothelial cell proliferation, migration, and tube formation in response to both vascular endothelial growth factor (VEGF)- and basic fibroblast growth factor (bFGF)-mediated angiogenic stimulation. In vivo, using primary xenograft models of human non-small cell lung cancer, oral itraconazole showed single agent growth-inhibitory activity associated with induction of tumor HIF1α expression and marked inhibition of tumor vascularity. Itraconazole significantly enhanced the anti-tumor efficacy of the chemotherapeutic agent cisplatin in the same model systems. Taken together, these data suggest that itraconazole has potent and selective inhibitory activity against multiple key aspects of tumor-associated angiogenesis in vitro and in vivo, and strongly support clinical translation of its use. Based on these observations we have initiated a randomized phase II study comparing the efficacy of standard cytotoxic therapy with or without daily oral itraconazole in patients with recurrent metastatic non-small cell lung cancer.
The promise of targeting epigenetic abnormalities for cancer therapy has not been realized for solid tumours, although increasing evidence is demonstrating its worth in haematological malignancies. In fact, true clinical efficacy in haematopoietic-related neoplasms has only become evident at low doses of epigenetic-targeting drugs (namely, inhibitors of histone deacetylase and DNA methyltransferases). Describing data from preclinical studies and early clinical trial results, we hypothesize that in using low-dose epigenetic-modulating agents, tumour cells can be reprogrammed, which overrides any immediate cytotoxic and off-target effect observed at high dose. We suggest that such optimization of drug dosing and scheduling of currently available agents could give these agents a prominent place in cancer management—when used alone or in combination with other therapies. If so, optimal use of these known agents might also pave the way for the introduction of other agents that target the epigenome.
We undertook this phase II study to measure postoperative drug delivery and toxicity of cisplatin plus docetaxel in patients with resected stage I-III non-small cell lung cancer.
The primary endpoint was amount of cisplatin delivered over a planned four cycles of adjuvant chemotherapy. Statistical design required a cohort to close if the regimen proved unlikely to improve cisplatin delivery compared with published phase III data. The first cohort was treated with docetaxel 35 mg/m2 intravenously (IV) on days 1, 8, and 15, and cisplatin 80 mg/m2 IV on day 15, every 4 weeks for four planned cycles. A second cohort was treated with docetaxel 75 mg/m2 IV plus cisplatin 80 mg/m2 IV on day 1 every 3 weeks for four planned cycles.
Sixteen patients were treated with weekly docetaxel and cisplatin every 4 weeks, with five of 16 (31%) unable to complete three cycles. Subsequently, 11 patients were treated with docetaxel and cisplatin every 3 weeks, with six of 11 (55%) unable to complete three cycles. Among the 11 patients who failed to complete three cycles, the reasons for stopping included one or more of the following: fatigue (n = 8), nausea (n = 4), febrile neutropenia (n = 1), hypotension (n = 1), and nephrotoxicity (n = 1).
The combination of cisplatin at 80 mg/m2 with docetaxel 35 mg/m2 weekly or 75 mg/m2 every 3 weeks is no better tolerated than older chemotherapy regimens. The most common reason to stop chemotherapy was intolerable fatigue. These results suggest that the most common dose-limiting toxicities are attributable to the cisplatin, given similar problems were encountered whether the docetaxel was delivered as a single dose every 3 weeks or as a lower weekly dose.
Non-small cell lung cancer; Adjuvant chemotherapy; Cisplatin; Docetaxel