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1.  Cisplatin/gemcitabine or oxaliplatin/gemcitabine in the treatment of advanced biliary tract cancer: a systematic review 
Cancer Medicine  2014;3(6):1502-1511.
Cisplatin/gemcitabine association has been a standard of care for first-line regimen in advanced biliary tract cancer nevertheless oxaliplatin/gemcitabine regimen is frequently preferred. Because comparative effectiveness in clinical outcomes of cisplatin- versus oxaliplatin-containing chemotherapy is not available, a systematic review of studies assessing cisplatin/gemcitabine or oxaliplatin/gemcitabine chemotherapies in advanced biliary tract cancer was performed. Published studies evaluating cisplatin/gemcitabine or oxaliplatin/gemcitabine in advanced biliary tract cancer were included. Each study was weighted according to the number of patients included. The primary objective was to assess weighted median of medians overall survival (mOS) reported for both regimens. Secondary goals were to assess weighted median of medians progression-free survival (mPFS) and toxic effects were pooled and compared within each arm. Thirty-three studies involving 1470 patients were analyzed. In total, 771 and 699 patients were treated by cisplatin/gemcitabine and oxaliplatin/gemcitabine, respectively. Weighted median of mOS was 9.7 months in cisplatin group and 9.5 months in oxaliplatin group. Cisplatin-based chemotherapy was significantly associated with more grade 3 and 4 asthenia, diarrhea, liver toxicity, and hematological toxicity. Sensitivity analysis including only the studies with the standard regimen of cisplatin (25–35 mg/m2 administered on days 1 and 8) showed that the weighted median of mOS increased from 9.7 to 11.7 months but Gem/CDDP regimen remained more toxic than Gemox regimen. These results suggest that the Gem/CDDP regimen with cisplatin (25–35 mg/m2) administered on days 1 and 8 is associated with survival advantage than Gemox regimen but with addition of toxicity.
doi:10.1002/cam4.299
PMCID: PMC4298376  PMID: 25111859
Biliary tract cancer; cisplatin; gemcitabine; oxaliplatin
2.  Constitutional and somatic deletions of the Williams-Beuren syndrome critical region in Non-Hodgkin Lymphoma 
Here, we report and investigate the genomic alterations of two novel cases of Non-Hodgkin Lymphoma (NHL) in children with Williams-Beuren syndrome (WBS), a multisystem disorder caused by 7q11.23 hemizygous deletion. Additionally, we report the case of a child with NHL and a somatic 7q11.23 deletion. Although the WBS critical region has not yet been identified as a susceptibility locus in NHL, it harbors a number of genes involved in DNA repair. The high proportion of pediatric NHL reported in WBS is intriguing. Therefore, the role of haploinsufficiency of genes located at 7q11.23 in lymphomagenesis deserves to be investigated.
Electronic supplementary material
The online version of this article (doi:10.1186/s13045-014-0082-4) contains supplementary material, which is available to authorized users.
doi:10.1186/s13045-014-0082-4
PMCID: PMC4228180  PMID: 25388916
Williams-Beuren syndrome; Non-Hodgkin Lymphoma; 7q11.23; Cancer predisposition; DNA repair
3.  Immunogenicity Evaluation of a Rationally Designed Polytope Construct Encoding HLA-A*0201 Restricted Epitopes Derived from Leishmania major Related Proteins in HLA-A2/DR1 Transgenic Mice: Steps toward Polytope Vaccine 
PLoS ONE  2014;9(10):e108848.
Background
There are several reports demonstrating the role of CD8 T cells against Leishmania species. Therefore peptide vaccine might represent an effective approach to control the infection. We developed a rational polytope-DNA construct encoding immunogenic HLA-A2 restricted peptides and validated the processing and presentation of encoded epitopes in a preclinical mouse model humanized for the MHC-class-I and II.
Methods and Findings
HLA-A*0201 restricted epitopes from LPG-3, LmSTI-1, CPB and CPC along with H-2Kd restricted peptides, were lined-up together as a polytope string in a DNA construct. Polytope string was rationally designed by harnessing advantages of ubiquitin, spacers and HLA-DR restricted Th1 epitope. Endotoxin free pcDNA plasmid expressing the polytope was inoculated into humanized HLA-DRB1*0101/HLA-A*0201 transgenic mice intramuscularly 4 days after Cardiotoxin priming followed by 2 boosters at one week interval. Mice were sacrificed 10 days after the last booster, and splenocytes were subjected to ex-vivo and in-vitro evaluation of specific IFN-γ production and in-vitro cytotoxicity against individual peptides by ELISpot and standard chromium-51(51Cr) release assay respectively. 4 H-2Kd and 5 HLA-A*0201 restricted peptides were able to induce specific CD8 T cell responses in BALB/C and HLA-A2/DR1 mice respectively. IFN-γ and cytolytic activity together discriminated LPG-3-P1 as dominant, LmSTI-1-P3 and LmSTI-1-P6 as subdominant with both cytolytic activity and IFN-γ production, LmSTI-1-P4 and LPG-3-P5 as subdominant with only IFN-γ production potential.
Conclusions
Here we described a new DNA-polytope construct for Leishmania vaccination encompassing immunogenic HLA-A2 restricted peptides. Immunogenicity evaluation in HLA-transgenic model confirmed CD8 T cell induction with expected affinities and avidities showing almost efficient processing and presentation of the peptides in relevant preclinical model. Further evaluation will determine the efficacy of this polytope construct protecting against infectious challenge of Leishmania. Fortunately HLA transgenic mice are promising preclinical models helping to speed up immunogenicity analysis in a human related mouse model.
doi:10.1371/journal.pone.0108848
PMCID: PMC4195657  PMID: 25310094
4.  Advanced biliary tract carcinomas: a retrospective multicenter analysis of first and second-line chemotherapy 
BMC Gastroenterology  2014;14:143.
Background
Gemcitabine/Cisplatin (Gem/CDDP) combination has demonstrated a clear survival advantage over gemcitabine alone and has become a new standard in advanced Biliary Tract Carcinoma (aBTC). However, Gemcitabine/Oxaliplatin (GEMOX) combination and Gemcitabine/Carboplatin (Gem/Carb) combination regimens have shown efficacy in phase II trials and there is no comparative study between different platinum salts.
We assessed the efficacy and safety of different platinum-based chemotherapies at first line in aBTC patients. We also analysed the second-line chemotherapy.
Methods
Sixty-four consecutive patients with aBTC diagnosed between 1998 and 2010 were included for analysis. At first line chemotherapy, 44 patients received one day GEMOX regimen (gemcitabine 1000 mg/m2 and oxaliplatin 100 mg/m2 Day 1, every 2 weeks), and 20 patients received Gem/Carb regimen (gemcitabine at 1000 mg/m2 Days 1 and 8 with carboplatin delivered according to an area-under-the-curve (AUC) 5 at day 1, every 3 weeks). At second line, a total of 16 patients received a fluoropyrimidine-based chemotherapy.
Results
With GEMOX regimen, median progression-free survival (PFS) was 3.7 months (95%CI, 2.4 to 5) and median overall survival (OS) was 10.5 months (95%CI, 6.4 to14.7). The main toxicity was peripheral neuropathy (20% grade 2 and 7% grade 3). Grade 3/4 haematological toxicities were rare.
With Gem/Carb regimen, PFS was 2.5 months (95%CI, 2.1 to 3.7) and OS was 4.8 months (95%CI, 3.7 to 5.8). The main grade 3/4 toxicities were haematological: anaemia (45%), thrombocytopenia (45%), and neutropenia (40%).
At second-line, fluoropyrimidine-based chemotherapy was feasible in only a fourth of the patients. The median OS was 5.3 months (95%CI, 4.1 to 6.6), and median PFS was 4.0 months (95%CI, 2.6 to 5.5).
Conclusions
One day GEMOX regimen has a favourable toxicity profile and could be an alternative to standard Gem/CDDP regimen, in particular in unfit patients for CDDP.
At second-line, selective patients may benefit from fluoropyrimidine-based chemotherapy.
doi:10.1186/1471-230X-14-143
PMCID: PMC4236575  PMID: 25117717
5.  Targeting antitumor CD4 helper T cells with universal tumor-reactive helper peptides derived from telomerase for cancer vaccine 
Human Vaccines & Immunotherapeutics  2013;9(5):1073-1077.
Current cancer immunotherapies predominantly rely on CD8+ T cells to fight against tumors. However accumulative evidence showed that proinflammatory CD4+ helper T cells are critical determinants of effective antitumor immunity. The utilization of universal tumor-reactive helper peptides from telomerase represents a powerful approach to the fully use of CD4+ T cell-based immunotherapy.
doi:10.4161/hv.23587
PMCID: PMC3899142  PMID: 23357860
CD4 T cell; helper peptide; telomerase; cancer vaccine
6.  Human Monocyte-Derived Dendritic Cells Exposed to Microorganisms Involved in Hypersensitivity Pneumonitis Induce a Th1-Polarized Immune Response 
Hypersensitivity pneumonitis (HP) is an immunoallergic disease characterized by a prominent interstitial infiltrate composed predominantly of lymphocytes secreting inflammatory cytokines. Dendritic cells (DCs) are known to play a pivotal role in the lymphocytic response. However, their cross talk with microorganisms that cause HP has yet to be elucidated. This study aimed to investigate the initial interactions between human monocyte-derived DCs (MoDCs) and four microorganisms that are different in nature (Saccharopolyspora rectivirgula [actinomycetes], Mycobacterium immunogenum [mycobacteria], and Wallemia sebi and Eurotium amstelodami [filamentous fungi]) and are involved in HP. Our objectives were to determine the cross talk between MoDCs and HP-causative agents and to determine whether the resulting immune response varied according to the microbial extract tested. The phenotypic activation of MoDCs was measured by the increased expression of costimulatory molecules and levels of cytokines in supernatants. The functional activation of MoDCs was measured by the ability of MoDCs to induce lymphocytic proliferation and differentiation in a mixed lymphocytic reaction (MLR). E. amstelodami-exposed (EA) MoDCs expressed higher percentages of costimulatory molecules than did W. sebi-exposed (WS), S. rectivirgula-exposed (SR), or M. immunogenum-exposed (MI) MoDCs (P < 0.05, Wilcoxon signed-rank test). EA-MoDCs, WS-MoDCs, SR-MoDCs, and MI-MoDCs induced CD4+ T cell proliferation and a Th1-polarized immune response. The present study provides evidence that, although differences were initially observed between MoDCs exposed to filamentous fungi and MoDCs exposed to bacteria, a Th1 response was ultimately promoted by DCs regardless of the microbial extract tested.
doi:10.1128/CVI.00043-13
PMCID: PMC3754498  PMID: 23720369
7.  QSOX1 Inhibits Autophagic Flux in Breast Cancer Cells 
PLoS ONE  2014;9(1):e86641.
The QSOX1 protein (Quiescin Sulfhydryl oxidase 1) catalyzes the formation of disulfide bonds and is involved in the folding and stability of proteins. More recently, QSOX1 has been associated with tumorigenesis and protection against cellular stress. It has been demonstrated in our laboratory that QSOX1 reduces proliferation, migration and invasion of breast cancer cells in vitro and reduces tumor growth in vivo. In addition, QSOX1 expression has been shown to be induced by oxidative or ER stress and to prevent cell death linked to these stressors. Given the function of QSOX1 in these two processes, which have been previously linked to autophagy, we wondered whether QSOX1 might be regulated by autophagy inducers and play a role in this catabolic process. To answer this question, we used in vitro models of breast cancer cells in which QSOX1 was overexpressed (MCF-7) or extinguished (MDA-MB-231). We first showed that QSOX1 expression is induced following amino acid starvation and maintains cellular homeostasis. Our results also indicated that QSOX1 inhibits autophagy through the inhibition of autophagosome/lysosome fusion. Moreover, we demonstrated that inhibitors of autophagy mimic the effect of QSOX1 on cell invasion, suggesting that its role in this process is linked to the autophagy pathway. Previously published data demonstrated that extinction of QSOX1 promotes tumor growth in NOG mice. In this study, we further demonstrated that QSOX1 null tumors present lower levels of the p62 protein. Altogether, our results demonstrate for the first time a role of QSOX1 in autophagy in breast cancer cells and tumors.
doi:10.1371/journal.pone.0086641
PMCID: PMC3901705  PMID: 24475161
8.  Bevacizumab Efficacy in Metastatic Colorectal Cancer is Dependent on Primary Tumor Resection 
Annals of Surgical Oncology  2014;21(5):1632-1640.
Purpose
Bevacizumab plus fluoropyrimidine-based chemotherapy is standard treatment for first-line and second-line metastatic colorectal cancer (mCRC). However, to date, there is no current biomarker predictive for the benefit of bevacizumab use for these patients. Preclinical data suggest that the presence of the primary tumor could be involved in less efficient antitumor activity of antiangiogenic agents, but no clinical data currently support this hypothesis.
Methods
We performed a retrospective analysis of factors associated with overall survival (OS) in a study cohort of 409 mCRC patients. Univariate and multivariate Cox proportional hazard regression models were used to assess the influence of primary tumor resection and bevacizumab use on OS. We evaluated associations linking bevacizumab use and OS among patients who previously underwent or did not undergo primary tumor resection. Results were externally validated in a second independent cohort of 328 mCRC patients.
Results
In the study cohort, bevacizumab use and resection of the primary tumor were associated with improved OS. However, subgroup analyses indicate that bevacizumab did not influence survival of patients bearing a primary colorectal tumor (hazard ratio (HR) 0.98, 95 % confidence interval (CI) 0.60–1.61, log-rank test P = 0.6). By contrast, the survival benefit of bevacizumab was restricted to patients who previously underwent primary tumor resection (HR 0.71, 95 % CI 0.55–0.92, P = 0.009). Similar results were observed in the validation cohort.
Conclusions
Addition of bevacizumab to chemotherapy is associated with improvement of OS only in patients with primary tumor resection. These data support the rationale to validate prospectively the influence of primary tumor resection on bevacizumab antitumor effect in synchronous mCRC.
Electronic supplementary material
The online version of this article (doi:10.1245/s10434-013-3463-y) contains supplementary material, which is available to authorized users.
doi:10.1245/s10434-013-3463-y
PMCID: PMC3975091  PMID: 24419756
9.  Bifractionated CPT-11 with LV5FU2 infusion (FOLFIRI-3) in combination with bevacizumab: clinical outcomes in first-line metastatic colorectal cancers according to plasma angiopoietin-2 levels 
BMC Cancer  2013;13:611.
Background
Optimization of chemotherapy effectiveness in metastatic colorectal cancers (mCRC) is a major endpoint to enhance the possibility of curative intent surgery. FOLFIRI3 has shown promising results as second-line chemotherapy for mCRC patients previously exposed to oxaliplatin. The clinical efficacy of FOLFIRI3 was never determined in association with bevacizumab in non-previously treated mCRC patients.
Methods
We conducted a phase II clinical trial to characterize the response rate and toxicity profile of FOLFIRI3-bevacizumab as initial treatment for mCRC. Sixty-one patients enrolled in 3 investigation centers were treated with FOLFIRI3-bevacizumab (median of 10 cycles) followed by a maintenance therapy combining bevacizumab and capecitabine. Levels of plasma angiopoietin-2 (Ang-2) were measured by enzyme-linked immunosorbent assay at baseline.
Results
Overall response rate (ORR) was 66.7% (8% of complete and 58% of partial responses). The disease control rate was 91.7%. After a median time of follow-up of 46.7 months, 56 patients (92%) had progressed or died. The median progression free survival (PFS) was 12.7 months (95% confidence interval (CI) 9.7-15.8 months). The median overall survival (OS) was 24.5 months (95% CI: 10.6-38.3 months). Twenty-one patients underwent curative intent-surgery including 4 patients with disease initially classified as unresectable. Most common grade III-IV toxicities were diarrhea (15%), neutropenia (13%), asthenia (10%), and infections (4%). Hypertension-related medications needed to be increased in 3 patients. In multivariate analysis, surgery of metastases and Ang-2 levels were the only independent prognostic factors for PFS and OS. Indeed, baseline level of Ang-2 above 5 ng/mL was confirmed as an independent prognostic factor for progression free survival (HR = 0.357; 95% CI: 0.168-0.76, p = 0.005) and overall survival (HR = 0.226; 95% CI: 0.098-0.53, p = 0.0002).
Conclusions
As front-line therapy, FOLFIRI-3-bevacizumab is associated with an acceptable toxicity and induced promising objective response rates. However, unfavorable clinical outcomes were observed in patients with high levels of angiopoietin-2.
doi:10.1186/1471-2407-13-611
PMCID: PMC3877948  PMID: 24373251
Colorectal cancer; Bevacizumab; FOLFIRI3; Irinotecan; Angiopoietin-2
10.  Time to health-related quality of life score deterioration as a modality of longitudinal analysis for health-related quality of life studies in oncology: do we need RECIST for quality of life to achieve standardization? 
Quality of Life Research  2013;24:5-18.
Purpose
Longitudinal analysis of health-related quality of life (HRQoL) remains unstandardized and compromises comparison of results between trials. In oncology, despite available statistical approaches, results are poorly used to change standards of care, mainly due to lack of standardization and the ability to propose clinical meaningful results. In this context, the time to deterioration (TTD) has been proposed as a modality of longitudinal HRQoL analysis for cancer patients. As for tumor response and progression, we propose to develop RECIST criteria for HRQoL.
Methods
Several definitions of TTD are investigated in this paper. We applied this approach in early breast cancer and metastatic pancreatic cancer with a 5-point minimal clinically important difference. In breast cancer, TTD was defined as compared to the baseline score or to the best previous score. In pancreatic cancer (arm 1: gemcitabine with FOLFIRI.3, arm 2: gemcitabine alone), the time until definitive deterioration (TUDD) was investigated with or without death as event.
Results
In the breast cancer study, 381 women were included. The median TTD was influenced by the choice of the reference score. In pancreatic cancer study, 98 patients were enrolled. Patients in Arm 1 presented longer TUDD than those in Arm 2 for most of HRQoL scores. Results of TUDD were slightly different according to the definition of deterioration applied.
Conclusion
Currently, the international ARCAD group supports the idea of developing RECIST for HRQoL in pancreatic and colorectal cancer with liver metastasis, with a view to using HRQoL as a co-primary endpoint along with a tumor parameter.
Electronic supplementary material
The online version of this article (doi:10.1007/s11136-013-0583-6) contains supplementary material, which is available to authorized users.
doi:10.1007/s11136-013-0583-6
PMCID: PMC4282717  PMID: 24277234
Health-related quality of life; Clinical trials; Oncology; Longitudinal analysis; Time to deterioration
11.  Is preexisting antitumor CD4 T cell response indispensable for the chemotherapy induced immune regression of cancer? 
Oncoimmunology  2012;1(9):1617-1619.
Insights into antitumor T-cell responses may help the development of more efficient treatments for lung cancer. The interplay between preexisting antitumor CD4+ T-cell responses and platinum-based chemotherapy is crucial to improve patient survival. Accumulating evidence confirms that selecting cancer patients in whom chemotherapy can activate an anticancer immune response would largely improve the success of novel therapeutic approaches.
doi:10.4161/onci.21513
PMCID: PMC3525622  PMID: 23264913
immunomonitoring; models of immunochemotherapy and immunoradiotherapy; new targets; telomerase
12.  High expression of QSOX1 reduces tumorogenesis, and is associated with a better outcome for breast cancer patients 
Breast Cancer Research : BCR  2012;14(5):R136.
Introduction
The gene quiescin/sulfhydryl oxidase 1, QSOX1, encodes an enzyme directed to the secretory pathway and excreted into the extracellular space. QSOX1 participates in the folding and stability of proteins and thus could regulate the biological activity of its substrates in the secretory pathway and/or outside the cell. The involvement of QSOX1 in oncogenesis has been studied primarily in terms of its differential expression in systemic studies. QSOX1 is overexpressed in prostate cancers and in pancreatic adenocarcinoma. In contrast, QSOX1 gene expression is repressed in endothelial tumors. In the present study, we investigated the role of QSOX1 in breast cancer.
Methods
We analyzed QSOX1 mRNA expression in a cohort of 217 invasive ductal carcinomas of the breast. Moreover, we investigated QSOX1's potential role in regulating tumor growth and metastasis using cellular models in which we overexpressed or extinguished QSOX1 and xenograft experiments.
Results
We showed that the QSOX1 expression level is inversely correlated to the aggressiveness of breast tumors. Our results show that QSOX1 leads to a decrease in cell proliferation, clonogenic capacities and promotes adhesion to the extracellular matrix. QSOX1 also reduces the invasive potential of cells by reducing cell migration and decreases the activity of the matrix metalloproteinase, MMP-2, involved in these mechanisms. Moreover, in vivo experiments show that QSOX1 drastically reduces the tumor development.
Conclusions
Together, these results suggest that QSOX1 could be posited as a new biomarker of good prognosis in breast cancer and demonstrate that QSOX1 inhibits human breast cancer tumorogenesis.
doi:10.1186/bcr3341
PMCID: PMC4053115  PMID: 23098186
13.  Neuropilin-2 Expression Promotes TGF-β1-Mediated Epithelial to Mesenchymal Transition in Colorectal Cancer Cells 
PLoS ONE  2011;6(7):e20444.
Neuropilins, initially characterized as neuronal receptors, act as co-receptors for cancer related growth factors and were recently involved in several signaling pathways leading to cytoskeletal organization, angiogenesis and cancer progression. Then, we sought to investigate the ability of neuropilin-2 to orchestrate epithelial-mesenchymal transition in colorectal cancer cells. Using specific siRNA to target neuropilin-2 expression, or gene transfer, we first observed that neuropilin-2 expression endows HT29 and Colo320 for xenograft formation. Moreover, neuropilin-2 conferred a fibroblastic-like shape to cancer cells, suggesting an involvement of neuropilin-2 in epithelial-mesenchymal transition. Indeed, the presence of neuropilin-2 in colorectal carcinoma cell lines was correlated with loss of epithelial markers such as cytokeratin-20 and E-cadherin and with acquisition of mesenchymal molecules such as vimentin. Furthermore, we showed by surface plasmon resonance experiments that neuropilin-2 is a receptor for transforming-growth factor-β1. The expression of neuropilin-2 on colon cancer cell lines was indeed shown to promote transforming-growth factor-β1 signaling, leading to a constitutive phosphorylation of the Smad2/3 complex. Treatment with specific TGFβ-type1 receptor kinase inhibitors restored E-cadherin levels and inhibited in part neuropilin-2-induced vimentin expression, suggesting that neuropilin-2 cooperates with TGFβ-type1 receptor to promote epithelial-mesenchymal transition in colorectal cancer cells. Our results suggest a direct role of NRP2 in epithelial-mesenchymal transition and highlight a cross-talk between neuropilin-2 and TGF-β1 signaling to promote cancer progression. These results suggest that neuropilin-2 fulfills all the criteria of a therapeutic target to disrupt multiple oncogenic functions in solid tumors.
doi:10.1371/journal.pone.0020444
PMCID: PMC3128581  PMID: 21747928
14.  Neuropilins: A New Target for Cancer Therapy 
Cancers  2011;3(2):1899-1928.
Recent investigations highlighted strong similarities between neural crest migration during embryogenesis and metastatic processes. Indeed, some families of axon guidance molecules were also reported to participate in cancer invasion: plexins/semaphorins/neuropilins, ephrins/Eph receptors, netrin/DCC/UNC5. Neuropilins (NRPs) are transmembrane non tyrosine-kinase glycoproteins first identified as receptors for class-3 semaphorins. They are particularly involved in neural crest migration and axonal growth during development of the nervous system. Since many types of tumor and endothelial cells express NRP receptors, various soluble molecules were also found to interact with these receptors to modulate cancer progression. Among them, angiogenic factors belonging to the Vascular Endothelial Growth Factor (VEGF) family seem to be responsible for NRP-related angiogenesis. Because NRPs expression is often upregulated in cancer tissues and correlated with poor prognosis, NRPs expression might be considered as a prognostic factor. While NRP1 was intensively studied for many years and identified as an attractive angiogenesis target for cancer therapy, the NRP2 signaling pathway has just recently been studied. Although NRP genes share 44% homology, differences in their expression patterns, ligands specificities and signaling pathways were observed. Indeed, NRP2 may regulate tumor progression by several concurrent mechanisms, not only angiogenesis but lymphangiogenesis, epithelial-mesenchymal transition and metastasis. In view of their multiples functions in cancer promotion, NRPs fulfill all the criteria of a therapeutic target for innovative anti-tumor therapies. This review focuses on NRP-specific roles in tumor progression.
doi:10.3390/cancers3021899
PMCID: PMC3757396  PMID: 24212788
neuropilins; cancer; angiogenesis; lymphangiogenesis; targeted therapies
15.  Membrane-associated Hsp72 from tumor-derived exosomes mediates STAT3-dependent immunosuppressive function of mouse and human myeloid-derived suppressor cells 
Myeloid-derived suppressor cells (MDSCs) have been identified in humans and mice as a population of immature myeloid cells with the ability to suppress T cell activation. They accumulate in tumor-bearing mice and humans and have been shown to contribute to cancer development. Here, we have isolated tumor-derived exosomes (TDEs) from mouse cell lines and shown that an interaction between TDE-associated Hsp72 and MDSCs determines the suppressive activity of the MDSCs via activation of Stat3. In addition, tumor-derived soluble factors triggered MDSC expansion via activation of Erk. TDE-associated Hsp72 triggered Stat3 activation in MDSCs in a TLR2/MyD88-dependent manner through autocrine production of IL-6. Importantly, decreasing exosome production using dimethyl amiloride enhanced the in vivo antitumor efficacy of the chemotherapeutic drug cyclophosphamide in 3 different mouse tumor models. We also demonstrated that this mechanism is relevant in cancer patients, as TDEs from a human tumor cell line activated human MDSCs and triggered their suppressive function in an Hsp72/TLR2-dependent manner. Further, MDSCs from cancer patients treated with amiloride, a drug used to treat high blood pressure that also inhibits exosome formation, exhibited reduced suppressor functions. Collectively, our findings show in both mice and humans that Hsp72 expressed at the surface of TDEs restrains tumor immune surveillance by promoting MDSC suppressive functions.
doi:10.1172/JCI40483
PMCID: PMC2810085  PMID: 20093776
16.  Vaccination of metastatic melanoma patients with autologous dendritic cell (DC) derived-exosomes: results of thefirst phase I clinical trial 
Background
DC derived-exosomes are nanomeric vesicles harboring functional MHC/peptide complexes capable of promoting T cell immune responses and tumor rejection. Here we report the feasability and safety of the first Phase I clinical trial using autologous exosomes pulsed with MAGE 3 peptides for the immunization of stage III/IV melanoma patients. Secondary endpoints were the monitoring of T cell responses and the clinical outcome.
Patients and methods
Exosomes were purified from day 7 autologous monocyte derived-DC cultures. Fifteen patients fullfilling the inclusion criteria (stage IIIB and IV, HLA-A1+, or -B35+ and HLA-DPO4+ leukocyte phenotype, tumor expressing MAGE3 antigen) were enrolled from 2000 to 2002 and received four exosome vaccinations. Two dose levels of either MHC class II molecules (0.13 versus 0.40 × 1014 molecules) or peptides (10 versus 100 μg/ml) were tested. Evaluations were performed before and 2 weeks after immunization. A continuation treatment was performed in 4 cases of non progression.
Results
The GMP process allowed to harvest about 5 × 1014 exosomal MHC class II molecules allowing inclusion of all 15 patients. There was no grade II toxicity and the maximal tolerated dose was not achieved. One patient exhibited a partial response according to the RECIST criteria. This HLA-B35+/A2+ patient vaccinated with A1/B35 defined CTL epitopes developed halo of depigmentation around naevi, a MART1-specific HLA-A2 restricted T cell response in the tumor bed associated with progressive loss of HLA-A2 and HLA-BC molecules on tumor cells during therapy with exosomes. In addition, one minor, two stable and one mixed responses were observed in skin and lymph node sites. MAGE3 specific CD4+ and CD8+ T cell responses could not be detected in peripheral blood.
Conclusion
The first exosome Phase I trial highlighted the feasibility of large scale exosome production and the safety of exosome administration.
doi:10.1186/1479-5876-3-10
PMCID: PMC554765  PMID: 15740633
exosomes; dendritic cells; phase I trial; cancer vaccine; immunotherapy
17.  Novel mode of action of c-kit tyrosine kinase inhibitors leading to NK cell–dependent antitumor effects 
Journal of Clinical Investigation  2004;114(3):379-388.
Mutant isoforms of the KIT or PDGF receptors expressed by gastrointestinal stromal tumors (GISTs) are considered the therapeutic targets for STI571 (imatinib mesylate; Gleevec), a specific inhibitor of these tyrosine kinase receptors. Case reports of clinical efficacy of Gleevec in GISTs lacking the typical receptor mutations prompted a search for an alternate mode of action. Here we show that Gleevec can act on host DCs to promote NK cell activation. DC-mediated NK cell activation was triggered in vitro and in vivo by treatment of DCs with Gleevec as well as by a loss-of-function mutation of KIT. Therefore, tumors that are refractory to the antiproliferative effects of Gleevec in vitro responded to Gleevec in vivo in an NK cell–dependent manner. Longitudinal studies of Gleevec-treated GIST patients revealed a therapy-induced increase in IFN-γ production by NK cells, correlating with an enhanced antitumor response. These data point to a novel mode of antitumor action for Gleevec.
doi:10.1172/JCI200421102
PMCID: PMC489961  PMID: 15286804
18.  Sirolimus enhances the effect of apoptotic cell infusion on hematopoietic engraftment and tolerance induction 
Leukemia  2007;22(7):1430-1434.
doi:10.1038/sj.leu.2405061
PMCID: PMC3421632  PMID: 18059479
Animals; Apoptosis; drug effects; Bone Marrow Cells; physiology; Hematopoietic Stem Cell Transplantation; Immune Tolerance; Immunosuppressive Agents; pharmacology; Mice; Mice, Inbred BALB C; Photopheresis; Sirolimus; pharmacology; T-Lymphocytes, Regulatory; immunology; Transplantation Conditioning

Results 1-18 (18)