The combination of molecular chemotherapy with radiation therapy has the potential to become a powerful approach for treatment of pancreatic cancer. We have developed an adenoviral vector (AdbCD-D314A) encoding a mutant bacterial cytosine deaminase (bCD) gene, which converts the prodrug 5-fluorocytosine (5-FC) into the active drug 5-fluorouracil. The aim of this study was to investigate AdbCD-D314A/5-FC-mediated cytotoxicity in vitro and therapeutic efficacy in vivo alone and in combination with radiation against human pancreatic cancer cells and xenografts. AdbCD-D314A/5-FC-mediated cytotoxicity alone and in combination with radiation was analyzed using crystal violet inclusion and clonogenic survival assays. CD enzyme activity was determined by measuring conversion of [ 3

This study demonstrates the efficacy of the death receptor monoclonal antibody TRA-8 in combination with conventional chemotherapy in an ex vivo human ovarian cancer model. This model can be used to assess cytotoxicity of novel agents in combination with chemotherapy in ovarian cancer.

Aim: To molecularly characterize the tumor microenvironment and evaluate immunologic parameters in canine glioma patients before and after treatment with oncolytic human IL-12-expressing herpes simplex virus (M032) and in treatment naïve canine gliomas. Methods: We assessed pet dogs with sporadically occurring gliomas enrolled in Stage 1 of a veterinary clinical trial that was designed to establish the safety of intratumoral oncoviral therapy with M032, a genetically modified oncolytic herpes simplex virus. Specimens from dogs in the trial and dogs not enrolled in the trial were evaluated with immunohistochemistry, NanoString, Luminex cytokine profiling, and multi-parameter flow cytometry. Results: Treatment-naive canine glioma microenvironment had enrichment of Iba1 positive macrophages and minimal numbers of T and B cells, consistent with previous studies identifying these tumors as immunologically “cold”. NanoString mRNA profiling revealed enrichment for tumor intrinsic pathways consistent with suppression of tumor-specific immunity and support of tumor progression. Oncolytic viral treatment induced an intratumoral mRNA transcription signature of tumor-specific immune responses in 83% (5/6) of canine glioma patients. Changes included mRNA signatures corresponding with interferon signaling, lymphoid and myeloid cell activation, recruitment, and T and B cell immunity. Multiplexed protein analysis identified a subset of oligodendroglioma subjects with increased concentrations of IL-2, IL-7, IL-6, IL-10, IL-15, TNFα, GM-CSF between 14 and 28 days after treatment, with evidence of CD4+ T cell activation and modulation of IL-4 and IFNγ production in CD4+ and CD8+ T cells isolated from peripheral blood. Conclusion: These findings indicate that M032 modulates the tumor-immune microenvironment in the canine glioma model.

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The human lung resistance protein (LRP) is a multidrug resistance protein that has been shown to be overexpressed in numerous chemotherapy resistance models. The precise role of LRP in platinum-resistant epithelial ovarian cancer (EOC) has yet to be fully elucidated. In this study, we sought to determine LRP expression in the tumor cells of ovarian cancer patient ascites of chemotherapy-naïve patients with advanced EOC. After IRB approval was obtained, patient ascites was collected and evaluated for platinum sensitivity, and LRP expression using western blot and immunohistochemistry (IHC). Both patient ascites and primary tumor were treated with 50 uM carboplatin for 48h and cell viability was analyzed. LRP, activated Caspase 3, and tunnel were analyzed using IHC on samples treated with 50uM carboplatin and untreated. A total of 27 patients with advanced-stage EOC undergoing primary cytoreductive surgery at the University of Alabama at Birmingham were consented for the study. Ten patient ascites samples were deemed adequate for analysis. Of these, 3/10 (30%) had increased LRP levels in ascites samples demonstrated by strong IHC staining with capping and confirmed by western blot. These patient samples were platinum resistant as verified by cytotoxicity analysis. Two ascites specimens (20%) lacked LRP expression by IHC and western blot and demonstrated platinum sensitivity on cytotoxicity. Five ascites specimens (50%) displayed intermediate LRP staining and platinum cytotoxicity. Tumor cells in ascites treated with carboplatin had an inverse correlation of LRP staining and activated Caspase 3. There is a strong correlation between LRP expression in the ascites of patients with advanced EOC and platinum resistance in this ex vivo model. This protein may therefore predict poor prognosis disease unlikely to respond to adjuvant platinum therapy. Specifically targeting the LRP in a clinical model may reverse carboplatin resistance. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 2688.