Oxana V. Makarova-Rusher

The yin and yang of evasion and immune activation in HCC

Current systemic treatment options for patients with hepatocellular carcinoma (HCC) are limited to sorafenib. With the recent FDA approval of the second PD1-PD-L1 pathway inhibitor, immunotherapy has gained even more interest as a potential novel treatment option for patients with HCC. This is due not only because of the failure of other treatment approaches in the past, but also because immunological mechanisms have been shown to play an important role during tumor development, growth, and treatment. Here we present a review of immunological mechanisms in the liver relevant for tumor progression and treatment. We summarize our current knowledge on immune activating and immune suppressing mechanisms during tumor initiation, development, and treatment. We try to explain the paradox of how inflammatory responses in a setting of chronic infection promote tumor development, while the primary aim of immunotherapy is to activate immunity. Finally we summarize recent advances in addition to providing an outlook for the immunotherapy of HCC.

Population attributable fractions of risk factors for hepatocellular carcinoma in the United States

Hepatocellular carcinoma (HCC) incidence has been increasing in the United States for several decades; and, as the incidence of hepatitis C virus (HCV) infection declines and the prevalence of metabolic disorders rises, the proportion of HCC attributable to various risk factors may be changing.

A phase II study of TRC105 in patients with hepatocellular carcinoma who have progressed on sorafenib

Background Endoglin is an endothelial cell membrane receptor essential for angiogenesis and highly expressed on the vasculature of many tumor types, including hepatocellular carcinoma (HCC). TRC105 is a chimeric IgG1 anti-CD105 monoclonal antibody that inhibits angiogenesis and tumor growth by endothelial cell growth inhibition, ADCC and apoptosis, and complements VEGF inhibitors. Objective The aim of this phase II study was to evaluate the efficacy of anti-endoglin therapy with TRC105 in patients with advanced HCC, post-sorafenib. Methods Patients with HCC and compensated liver function (Childs-Pugh A/B7), ECOG 0/1, were enrolled to a single-arm, phase II study of TRC105 15 mg/kg IV every two weeks. Patients must have progressed on or been intolerant of prior sorafenib. A Simon optimal two-stage design was employed with a 50% four-month PFS target for progression to the second stage. Correlative biomarkers evaluated included DCE-MRI as well as plasma levels of angiogenic biomarkers and soluble CD105. Results A total accrual of 27 patients was planned. However, because of lack of efficacy and in accordance with the Simon two-stage design, 11 patients were enrolled. There were no grade 3/4 treatment-related toxicities. Most frequent toxicities were headache (G2; N = 3) and epistaxis (G1; N = 4). One patient had a confirmed partial response by standard RECIST criteria and biologic response on DCE-MRI but the four-month PFS was insufficient to proceed to the second stage of the study. Conclusions: TRC105 was well tolerated in this HCC population following sorafenib. Although there was evidence of clinical activity, this did not meet prespecified criteria to proceed to the second stage. TRC105 development in HCC continues as combination therapy with sorafenib.

Pancreatic Squamous Cell Carcinoma: A Population-Based Study of Epidemiology, Clinicopathologic Characteristics and Outcomes.

Objectives Squamous metaplasia is commonly detected in pancreatic parenchyma; however, primary pancreatic squamous cell carcinoma (SCC) is a rare malignancy with unknown incidence and unclear prognosis. Methods Surveillance, Epidemiology, and End Results (SEER) registries were examined identifying pancreatic SCC and adenocarcinoma cases from 2000 to 2012. Age-adjusted incidence rates were calculated. Patients with SCC versus adenocarcinoma were compared by clinical features and relative survival outcomes. Results We identified 214 patients with SCC and 72,860 with adenocarcinoma. For SCC, incidence rates tripled between 2000 and 2012. Significantly higher SCC incidence rates were observed in older age groups, blacks, and males. Greater proportion of patients with SCC than those with adenocarcinoma had poorly differentiated histology (73.0% vs 43.7%, P < 0.001). In both subtypes, majority of patients had stage IV disease, 59.0% for adenocarcinoma versus 62.6% for SCC. The 1- and 2-year relative survival rate was significantly lower in patients with SCC versus adenocarcinoma. The 1-year relative survival was 14.0% (95% confidence interval, 9.5%–19.4%) for SCC, compared with 24.5% (95% confidence interval, 24.2%–24.8%) for adenocarcinoma. Conclusions Although primary pancreatic SCC is a rare neoplasm, incidence rates for this subtype are increasing. Relative to adenocarcinoma, pancreatic SCC is characterized by poorly differentiated histology and worse survival.

Modulation of tumor eIF4E by antisense inhibition: A phase I/II translational clinical trial of ISIS 183750 – an antisense oligonucleotide against eIF4E – in combination with irinotecan in solid tumors and irinotecan‐refractory colorectal cancer

The eukaryotic translation initiation factor 4E (eIF4E) is a potent oncogene that is found to be dysregulated in 30% of human cancer, including colorectal carcinogenesis (CRC). ISIS 183750 is a second‐generation antisense oligonucleotide (ASO) designed to inhibit the production of the eIF4E protein. In preclinical studies we found that EIF4e ASOs reduced expression of EIF4e mRNA and inhibited proliferation of colorectal carcinoma cells. An additive antiproliferative effect was observed in combination with irinotecan. We then performed a clinical trial evaluating this combination in patients with refractory cancer. No dose‐limiting toxicities were seen but based on pharmacokinetic data and tolerability the dose of irinotecan was reduced to 160 mg/m2 biweekly. Efficacy was evaluated in 15 patients with irinotecan‐refractory colorectal cancer. The median time of disease control was 22.1 weeks. After ISIS 183750 treatment, peripheral blood levels of eIF4E mRNA were decreased in 13 of 19 patients. Matched pre‐ and posttreatment tumor biopsies showed decreased eIF4E mRNA levels in five of nine patients. In tumor tissue, the intracellular and stromal presence of ISIS 183750 was detected by IHC in all biopsied patients. Although there were no objective responses stable disease was seen in seven of 15 (47%) patients who were progressing before study entry, six of whom were stable at the time of the week 16 CT scan. We were also able to confirm through mandatory pre‐ and posttherapy tumor biopsies penetration of the ASO into the site of metastasis.

Phase I and Preliminary Phase II Study of TRC105 in Combination with Sorafenib in Hepatocellular Carcinoma

Purpose: Endoglin (CD105) is an endothelial cell membrane receptor highly expressed on proliferating tumor vasculature, including that of hepatocellular carcinoma (HCC), and is associated with poor prognosis. Endoglin is essential for angiogenesis, and its expression is induced by hypoxia and VEGF pathway inhibition. TRC105 is a chimeric IgG1 CD105 mAb that inhibits angiogenesis and causes antibody-dependent cellular cytotoxicity and apoptosis of proliferating endothelium. Experimental Design: Patients with HCC (Child–Pugh A/B7), ECOG 0/1, were enrolled in a phase I study of TRC105 at 3, 6, 10, and 15 mg/kg every 2 weeks given with sorafenib 400 mg twice daily. Correlative biomarkers included DCE-MRI and plasma levels of angiogenic factors, including soluble endoglin. Pharmacokinetics were assessed in serum. Results: Twenty-six patients were enrolled, of whom 25 received treatment, 15 with cirrhosis. Hep B/C: 3/15; M:F 19:6; mean age of 60 (range, 18–76); 1 DLT (grade 3 AST) occurred at 10 mg/kg. The most frequent toxicity was low-grade epistaxis, a known toxicity of TRC105. One patient experienced an infusion reaction and was replaced. One patient with coronary stenosis developed a fatal myocardial infarction, and one patient developed G3 cerebral tumor hemorrhage. MTD was not established and DL4 (15 mg/kg) was expanded. The overall response rate in 24 evaluable patients at all 4 dose levels was 21% [95% confidence interval (CI), 7.1–42.2], and 25% (95% CI, 8.7–49.1) in patients with measureable disease. Four patients had confirmed stable disease, one of whom was treated for 22 months. Median progression-free survival (PFS) for 24 patients evaluable for PFS was 3.8 months (95% CI, 3.2–5.6 months); median overall survival was 15.5 months (95% CI, 8.5–26.3 months). Conclusions: TRC105 combined with sorafenib was well tolerated at the recommended single agent doses of both drugs. Encouraging evidence of activity to date (PR rate 25%) was observed, and the study is now continuing to recruit in the phase II stage as a multicenter study to confirm activity of the combination. Clin Cancer Res; 23(16); 4633–41. ©2017 AACR.

The case for immune‐based approaches in biliary tract carcinoma

Biliary tract cancers (BTC) comprise a group of uncommon malignancies in which the standard therapies are minimally effective and evolve slowly. Like the majority of gastrointestinal cancers, with some notable exceptions, the impact of immune‐based approaches has yet to be seen. However, the etiological background of BTC—overlapping in almost every known causative or associated factor with inflammation—provides a strong clue that these approaches may have an impact in this group of diseases. This review covers what we currently know about the role of the immune system in the etiology of BTC, highlighting differences by subtype, and pointing to the therapeutic opportunities currently entering the clinic or about to do so. (Hepatology 2016;64:1785‐1791)

Pancreatic squamous cell carcinoma: Epidemiology, clinicopathologic characteristics, and outcomes.

220 Background: Although squamous metaplasia is commonly detected in pancreatic parenchyma, primary pancreatic squamous cell carcinoma (SCC) is a rare malignancy with unknown incidence and unclear prognosis. Methods: Using SEER-18 database primary code C25 in conjunction with histology codes for SCC (8052-8053, 8070-8078, 8083-8084) and for adenocarcinoma (AC) (8052-8053, 807-8078, 8083-8084), we identified cases diagnosed from 2000 to 2012. Age-adjusted incidence rates and trends over time were calculated. Patients with SCC were compared with AC by clinical features (TNM categories and histological differentiation), and 1-year and 2-year relative survival (RS) outcomes. Chi-square tests for categorical variables and t-tests for continuous variables were conducted. Kaplan-Meier method was used to estimate RS and Z-test was used to compare RS rates. SEERStat and GraphPad were used for analysis. Results: We identified 214 patients with microscopically confirmed SCC and 72,860 patients with AC. SCC constitut...

Abstract A195: Tremelimimab activates CD4 and CD8+ T cells in patients with hepatocellular carcinoma

Introduction: Tremelimumab is a fully human monoclonal antibody that binds to CTLA-4 expressed on the surface of activated T lymphocytes and results in inhibition of B7-CTLA-4-mediated downregulation of T-cell activation. Patients with advanced hepatocellular carcinoma, who progressed on standard of care, were treated with tremelimumab and tumor ablation (radiofrequency ablation and transcatheter arterial chemoembolization) to augment anti-tumor immunity. Treatment was safe and feasible. Encouraging clinical activity has been seen with objective confirmed partial responses in 4/12 (33%) evaluable patients and a time to progression of 7.4 months. Here we report first results from immunoanalysis evaluating tumor biopsies, immune cell subsets in peripheral blood and serum viral loads in patients with chronic HBV or HCV infection. Methods: 20 Patients with HCC were treated with tremelimumab and tumor ablation on clinical trial NCT01853618. Tumor biopsies were taken at the time of ablation and peripheral blood mononuclear cells (PBMC) were collected before and during treatment in a subset of patients. Serum samples were tested for viral load (quantitative HCV RNA). Serum HBsAg titers were measured by chemiluminescent microparticle immunoassay (CMIA) using the ARCHITECT platform (Abbott Laboratories, Chicago, IL), as per the manufacturer9s instructions. Tumor biopsies with analyzed by immunohistochemistry for CD3, CD4, CD8, CD20 and Granzyme B. Eleven-color flow cytometry was performed to study PBMC using the following antibodies: CD4, CD3, CD4, CD8, CD11c, CD14, CD19, CD20, CD25, CD38, CD45RA, CD56, CD123, CD127, CCR7, CCR4, CXCR3, PD-1, 4-1BB, TIM3, CTLA4, PD-L1, ICOS, HLA-DR. Statistical analysis was done using the Wilcoxon signed rank test. Results presented are preliminary and update data will be presented at meeting. Results: Immunohistochemical analysis of tumor biopsies demonstrated an increase in the CD3+CD8+ T cell population in tumors. CD8+ T cells stained positive for Granzyme A. No changes in the number of CD68+ macrophages were seen. Multi-color flow cytotometry PBMC revealed statistically significant changes after the 1st cycle of activated CD4+ and CD8+ T cells. There was a trend towards a reduction in CD4+ Tregs. Activated CD8+ T cells remained elevated for more than three months. Eight of 9 patients with quantifiable HCV experienced a marked reduction in viral load. Four of 4 HBV patients experienced a reduction in quantitative HepBsAg. Analysis of immune cell phenotype and more in depth analysis of tumor samples is ongoing and will be reported. Conclusions: Tremelimumab in combination with subtotal TACE or RFA leads to an accumulation of intratumoral CD8+ T cells, an activation of CD4+ and CD8+ T cells in peripheral blood and reductions in HCV viral load and HBsAg. Citation Format: Firouzeh Korangy, Mei ElGindi, Drew Pratt, David Venzon, Austin Duffy, Oxana Makarova-Rusher, Sid Kerkar, David Kleiner, Bradford Wood, Tim Greten. Tremelimimab activates CD4 and CD8+ T cells in patients with hepatocellular carcinoma. [abstract]. In: Proceedings of the CRI-CIMT-EATI-AACR Inaugural International Cancer Immunotherapy Conference: Translating Science into Survival; September 16-19, 2015; New York, NY. Philadelphia (PA): AACR; Cancer Immunol Res 2016;4(1 Suppl):Abstract nr A195.

Abstract 3421: Epidemiology and survival in patients with extragastric signet ring carcinoma

Background: Signet ring carcinoma (SRC) is a distinct histological phenotype of adenocarcinoma. There are only a few published studies specifying the epidemiology of SRC with extragastric presentation. The purpose of our study was to define the most common primary sites of extragastric SRC, determine the incidence, and to compare survival by primary site and disease stage. Methods: The Surveillance Epidemiology and End Result (SEER) database was examined from 2000 to 2012 in order to identify SRC histology (8490) and determine its most common primary sites, incidence, and survival by site and stage. The five most common primary extragastric sites were identified by utilizing ICD-0-3/WHO 2008 classification. Age-adjusted incidence rates for extragastric SRC were calculated and compared to gastric SRC. Relative survival (RS) and overall survival (OS) at 1 and 3 years were analyzed by primary site and stage using Kaplan-Meier method. Chi-square test was used for categorical variables. Results: A total of 24,522 histologically confirmed cases of SRC were identified, and SRC comprised 0.5% of all malignant neoplasms. Among cases with known histological grade, 89.7% had poorly differentiated tumors. Overall, digestive system origin was recorded for 90% of SRC cases. Approximately half (44.2%) of primary SRC tumors were detected outside of the stomach. The most common primary sites for extragastric SRC were colon (40.5%), esophagus (11.9%), rectum (9.8%), lung/bronchus (7.3%), and pancreas (4.7%). The incidence rates for common extragastric SRC were much lower than for gastric SRC, and were higher for males than females (p Conclusion: Our study indicated that extragastric SRC most commonly occurs in the colorectum, esophagus and lung/bronchus. We confirmed that the primary site substantially impacts survival. Thus, development of unique molecular or histologic markers may help to identify the organ of origin and thereby determine prognosis in these phenotypically similar neoplasms. Citation Format: Chul Kim, Susanna Ulahannan, Julius Strauss, Jaydira Del Rivero, Austin Duffy, Tim F. Greten, Oxana V. Makarova-Rusher. Epidemiology and survival in patients with extragastric signet ring carcinoma. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 3421.