Future perspectives in melanoma research. Meeting report from the “Melanoma Bridge. Napoli, December 2nd-4th 2012”

Recent insights into the genetic and somatic aberrations have initiated a new era of rapidly evolving targeted and immune-based treatments for melanoma. After decades of unsuccessful attempts to finding a more effective cure in the treatment of melanoma now we have several drugs active in melanoma. The possibility to use these drugs in combination to improve responses to overcome the resistance, to potentiate the action of immune system with the new immunomodulating antibodies, and identification of biomarkers that can predict the response to a particular therapy represent new concepts and approaches in the clinical management of melanoma. The third “Melanoma Research: “A bridge from Naples to the World” meeting, shortened as “Bridge Melanoma Meeting” took place in Naples, December 2 to 4th, 2012. The four topics of discussion at this meeting were: advances in molecular profiling and novel biomarkers, combination therapies, novel concepts toward integrating biomarkers and therapies into contemporary clinical management of patients with melanoma across the entire spectrum of disease stage, and the knowledge gained from the biology of tumor microenvironment across different tumors as a bridge to impact on prognosis and response to therapy in melanoma. This international congress gathered more than 30 international faculty members who in an interactive atmosphere which stimulated discussion and exchange of their experience regarding the most recent advances in research and clinical management of melanoma patients

Effect of simvastatin on endothelial cell apoptosis mediated by Fas and TNF-α

Although there is evidence suggesting that statins may exert an endothelial protecting effect, recent in vitro data have shown that these compounds may induce endothelial cells (EC) apoptosis. We previously reported that the Fas-death receptor may induce apoptosis of the liver sinusoid endothelial cells (LSEC), and that TNF-α increases the susceptibility of these cells to suffer Fas-mediated apoptosis. Based on this evidence, in this study, we investigated the effect of simvastatin on Fas-mediated LSEC apoptosis. Simvastatin induced a significant reduction in LSEC viability, in a dose dependent manner, under serum-containing or serum-free conditions. This effect was prevented by mevalonate and GGPP, indicating the role of hydroxy-3-methylglutaryl-CoA reductase. The simvastatin effect on LSEC death was not associated with increased activation of caspase-3. We found that simvastatin increased the susceptibility of LSEC death mediated by Fas. Further, simvastatin increased LSEC-apoptosis induced by Fas and TNF-α. Mevalonate and GGPP partially prevented simvastatin-induced sensitization to LSEC death mediated by Jo2 and TNF-α, but not Jo2 alone. Simvastatin did not induce up-regulation of the Fas on the LSEC. Our results provide evidence of simvastatin in modulating Fas-mediated apoptosis in endothelial cells. These results may have clinical implications in those clinical conditions associated with high levels of FasL and TNF-α

Abstract 5093: In vitro, in vivo and molecular effects of stromal selective targeting by uPAR retargeted oncoytic measles virus on breast cancer progression

Abstract The tumor microenvironment is a relevant target for novel biological therapies. While it has been demonstrated that tumor-stromal cell interactions are important in the sensitivity of the cancer cells to oncolytic virues, few studies have investigated the direct effects of an oncolytic virus on the stroma, and its implications on the virus antitumor efficacy. MV-m-uPA and MV-h-uPA are fully retargeted, species specific, oncolytic measles viruses directed against murine or human urokinase receptor (uPAR). The effects of stromal selective targeting by uPAR retargeted MVs were investigated. In vitro infection, gene expression and cytotoxicity by MV-h-uPA and MV-m-uPA were demonstrated in human and murine cancer cells and cancer associated fibroblasts in a species specific manner. In murine fibroblast (3T3)/human breast cancer (T47D) 3-D co-cultures, selective fibroblast targeting by MV-m-uPA inhibited breast cancer cell growth.  These effects were validated in vivo, in a human breast cancer xenograft (MDA-MB-231), where intravenous administration of the murine specific MV-m-uPA led to significant tumor growth delay and improved survival compared to controls. Experiments comparing the effects of tumor (MV-h-uPA) vs. stromal (MV-m-uPA) vs. combined treatment showed that tumor and stromal targeting was associated with improved tumor control. Correlative studies demonstrated in vivo tumor targeting, increased apoptosis, and MV-m-uPA induced differential regulation of both stromal (murine) genes and cancer (human) genes associated with inflammation, angiogenesis and survival, among others, indicating viral induced modulation of tumor-stromal interactions. Our results demonstrate for the first time the feasibility of stromal selective targeting by an oncolytic MV, viral induced modulation of the tumor microenvironment, and subsequent tumor growth delay. These findings further validate the critical role of stromal uPAR in cancer progression and the potential of oncolytic viruses as anti-stromal agents. Citation Format: Yuqi Jing, Valery Chavez, Nicolas Acquavella, Doraya El-Ashry, Yuguang Ban, Xi Chen, Jaime Merchan. In vitro, in vivo and molecular effects of stromal selective targeting by uPAR retargeted oncoytic measles virus on breast cancer progression [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 5093. doi:10.1158/1538-7445.AM2017-5093</jats:p

Molecular Effects of Stromal-Selective Targeting by uPAR-Retargeted Oncolytic Virus in Breast Cancer

The tumor microenvironment (TME) is a relevant target for novel biological therapies. MV-m-uPA and MV-h-uPA are fully retargeted, species-specific, oncolytic measles viruses (MV) directed against murine or human urokinase receptor (PLAUR/uPAR), expressed in tumor and stromal cells. The effects of stromal-selective targeting by uPAR-retargeted MVs were investigated.infection, virus-induced GFP expression, and cytotoxicity by MV-h-uPA and MV-m-uPA were demonstrated in human and murine cancer cells and cancer-associated fibroblasts in a species-specific manner. In a murine fibroblast/human breast cancer 3D coculture model, selective fibroblast targeting by MV-m-uPA inhibited breast cancer cell growth. Systemic administration of murine-specific MV-m-uPA in mice bearing human MDA-MB-231 xenografts was associated with a significant delay in tumor progression and improved survival compared with controls. Experiments comparing tumor (MV-h-uPA) versus stromal (MV-m-uPA) versus combined virus targeting showed that tumor and stromal targeting was associated with improved tumor control over the other groups. Correlative studies confirmedviral targeting of tumor stroma by MV-m-uPA, increased apoptosis, and virus-induced differential regulation of murine stromal genes associated with inflammatory, angiogenesis, and survival pathways, as well as indirect regulation of human cancer pathways, indicating viral-induced modulation of tumor-stroma interactions. These data demonstrate the feasibility of stromal-selective targeting by an oncolytic MV, virus-induced modulation of tumor-stroma pathways, and subsequent tumor growth delay. These findings further validate the critical role of stromal uPAR in cancer progression and the potential of oncolytic viruses as antistromal agents.The current report demonstrates for the first time the biological,, andantitumor and molecular effects of stromal selective targeting by an oncolytic virus.

The evolving landscape of oncolytic virotherapy (OV) clinical trials (CT): Meta-analysis

e14636 Background: The number of new OV CT have been increasing along with the evolution of cancer immunotherapy. The OVs induce direct oncolysis and enhances the host innate and adaptive immunity. There are ongoing efforts to improve the anticancer efficacy of OVs with combinational strategies. However, there has been no direct comparison of OV CTs to evaluate their different dose levels, administration routes, frequencies, and the types of OVs and combinations. Methods: A random-effect meta-analysis was performed to evaluate pooled best ORR of all the existing OV phase II and III trials from publications and presented abstracts from ASCO, AACR, and ASGCT from 1/1/2016 to 12/4/2016. MeSH term “oncolytic” was used in PubMed. The inclusion criteria were: phase II or III, solid tumor, reported ORR. We evaluated the best ORR among different viruses, DNA vs. RNA, intratumoral (IT) vs. intravenous (IV) / intra-arterial (IA), and single vs. combination. Results: From 79 publications and 176 presented abstracts identified, 6 published studies and 12 presented abstracts were selected and pooled (n=875). The best ORRs were: DNA OV 23% (15 ~ 34%) vs. RNA OV 31% (13 ~ 58%), IT 36% (23 ~ 51%) vs. IV/IA 16% (10 ~ 25%), and single agent 22% (16 ~ 31%) vs. combinations 35% (17 ~ 58%). The combination OV CTs were either with chemotherapy (n= 144), chemoradiation (n= 23), or immunotherapy (n= 69). Each OV’s ORR is summarized in the table below. Direct comparison of the secondary endpoints: clinical outcome and adverse events will be presented with the poster. In general, the OV CTs had good overall safety profile and most adverse events were less than grade 3. Conclusions: The antitumor effect of OVs against solid tumors is evident and consistent in many trials. The largest data currently available is with herpes virus and coxsackie virus appears to have the best ORR possibly due to the combination with immunotherapy. The above results confirm the promising clinical activity of novel oncolytic viral vectors both alone and in combination. [Table: see text

A Phase Ib Study of Sotrastaurin, a PKC Inhibitor, and Alpelisib, a PI3Kα Inhibitor, in Patients with Metastatic Uveal Melanoma

Uveal melanoma (UM) is a rare subset of melanoma characterized by the presence of early initiating GNAQ/11 mutations, with downstream activation of the PKC, MAPK, and PI3Kα pathways. Activity has been observed with the PKC inhibitors sotrastaurin (AEB071) and darovasertib (IDE196) in patients with UM. Inhibition of the PI3K pathway enhances PKC inhibition in in vivo models. We therefore conducted a phase Ib study of sotrastaurin in combination with the PI3Kα inhibitor alpelisib to identify a tolerable regimen that may enhance the activity of PKC inhibition alone. Patients with metastatic uveal melanoma (n = 24) or GNAQ/11 mutant cutaneous melanoma (n = 1) were enrolled on escalating dose levels of sotrastaurin (100–400 mg BID) and alpelisib (200–350 mg QD). The primary objective was to identify the maximum tolerated dose (MTD) of these agents when administered in combination. Treatment-related adverse events (AE) occurred in 86% (any grade) and 29% (Grade 3). No Grade 4–5-related AEs occurred. Dose Level 4 (sotrastaurin 200 mg BID and alpelisib 350 mg QD) was identified as the maximum tolerated dose. Pharmacokinetic analysis demonstrated increasing concentration levels with increasing doses of sotrastaurin and alpelisib, without evidence of interaction between agents. Pharmacodynamic assessment of pMARCKS and pAKT protein expression with drug exposure suggested modest target inhibition that did not correlate with clinical response. No objective responses were observed, and median progression-free survival was 8 weeks (range, 3–51 weeks). Although a tolerable dose of sotrastaurin and alpelisib was identified with pharmacodynamic evidence of target inhibition and without evidence of a corresponding immunosuppressive effect, limited clinical activity was observed

Preliminary safety data from a randomized multicenter phase Ib/II study of neoadjuvant chemoradiation therapy (CRT) alone or in combination with pembrolizumab in patients with resectable or borderline resectable pancreatic cancer

4125 Background: Pancreatic cancer (PC) is a challenging target for immunotherapy.Tumor-infiltrating lymphocytes (TILs) do not reach the PC cells in significant numbers due to the presence of stroma and a suppressive microenvironment. Neoadjuvant chemoradiation (CRT) can increase the presence of TILs in the PC microenvironment. We hypothesized that combination of CRT and pembrolizumab can lead to further increase in TILs and their activation. Methods: Patients with resectable or borderline resectable PC have been randomized 2:1 to the investigational treatment (Arm A) to receive pembrolizumab 200mg IV every 3 weeks on days 1, 22, and 43 during concurrent CRT with capecitabine (825 mg/m2 orally twice daily, Monday-Friday, on days of radiation only) and radiation (50.4 Gy in 28 fractions over 28 days) or Arm B to receive only concurrent CRT with capecitabine. Restaging CT scan or MRI is performed at 4-6 weeks after completion of neoadjuvant treatment, and patients with resectable disease will undergo surgical resection. Here we report the preliminary safety data based on 22 enrolled patients. Results: As of February 3-2017,22 patients have been enrolled (14 Arm A and 8 Arm B). 50% of the patients had resectable disease (7 arm A; 4 arm B) and the other 50% had borderline resectable disease (7 Arm A; 4 arm B). Post-neoadjuvant therapy, 6 patients had unresectable disease (3 on each arm), and 14 patients underwent surgery (10 arm A and 4 arm B). There were 7 grade 3 treatment-related toxicities in Arm A (5 patients): 2 grade 3 diarrhea attributed to CRT; 4 grade 3 lymphopenias attributed to pembrolizumab, CRT or the combination; and one patient had elevated alkaline phosphatase probably related to the combination that met the definition of DLT and resolved after holding the treatment and receiving steroids. There was only one grade 3 toxicity on Arm B: lymphopenia attributed to CRT. No grade 4 toxicities have been reported on either arm. There were no major surgical complications reported within 30 days post-surgery. Conclusions: The combination of CRT and pembrolizuamb is safe based on the presented data. Clinical trial information: NCT02305186