Patel, Tushar

Abstract Background: Hepatocellular carcinoma (HCC) is a lethal malignancy that currently ranks fourth in cancer-related deaths in the US and is projected to become the third leading cause of cancer death in the US by 2030. Thus, there is a pressing need to identify modifying risk factors to improve survival after diagnosis of HCC. Statins and metformin are among the most commonly prescribed medications in the elderly in the US and there are experimental data suggesting that these medications may improve overall survival after cancer diagnosis; however, results from observational studies have been equivocal. We therefore investigated the potential benefits of pre- and post-diagnosis use of statins and metformin both independently and jointly on overall survival after diagnosis of HCC. Methods: The study was performed using data from the Surveillance, Epidemiology, and End Results (SEER-18) registry linked to Medicare claims data and included 8,922 elderly (≥65 years) patients diagnosed with HCC between 2009-2013. Data on metformin and statins use were extracted from the Medicare Part D Claims file and the patients were grouped as statins only users, metformin only users, both statins and metformin users, or neither (i.e., non-users, referent group). We assessed association of both pre-diagnosis (≥2 years) and post-diagnosis statins and metformin use on risk of death after diagnosis of HCC. Statins users were further categorized into high potency statins users (simvastatin, atorvastatin, and rosuvastatin) or low potency statins users (pravastatin, lovastatin, and fluvastatin) and compared with non-users. Cox proportional hazard models were used to calculate hazard ratios (HRs) and 95% confidence intervals (CIs), adjusting for multiple risk factors, including age sex, race, cancer stage at diagnosis, cancer grade, first course therapy, neighborhood level education and income, Charlson comorbidity index, and diabetes severity index. Results: Compared with non-users, post-diagnosis statins use was independently associated with 27% lower risk of death after diagnosis of HCC (HR=0.73, 95% CI: 0.60-0.88; p-value = 0.002), adjusting for pre-diagnosis statins use and other risk factors. Further analysis showed that the association for post-diagnosis statins use is evident only among high potency statins users (HR=0.72, 95% CI: 0.60-0.88; users versus non-users) but not low potency statins users (HR=0.83, 95% CI: 0.55-1.25; users versus non-users). No association was found for pre-diagnosis statins use or for pre- or post-diagnosis metformin use. Conclusions: This study suggests that post-diagnosis statins use, particularly high potency statins use, may improve overall survival after diagnosis of HCC. Metformin use, both before and after diagnosis of HCC, is not associated with overall survival. Citation Format: Samuel O. Antwi, Zhuo Li, Kabir Mody, Tushar C. Patel. Independent and joint use of statins and metformin on overall survival after diagnosis of hepatocellular carcinoma: A SEER-Medicare matched study [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 1192.

Introduction and aim: Combined hepatocellular-cholangiocarcinoma (HCC-CCA) is a rare liver malignancy distinct from either hepatocellular carcinoma (HCC) or cholangiocarcinoma. Liver transplantation (LT) is not recommended for HCC-CCA because of suboptimal outcomes. Because non-invasive diagnosis of HCC-CCA is extremely challenging, some HCC-CCAs are presumed as HCC on imaging and listed for LT with the correct diagnosis ultimately made on explant pathology. We compared HCC-CCA with HCC to determine the utility of response to pre-transplant loco-regional therapy (LRT) in predicting outcomes for HCC-CCA after LT as a potential means of identifying appropriate HCC-CCA patients for LT. Materials and methods: Retrospective review of 19 patients with pathologically confirmed HCC-CCA individually matched to 38 HCC patients based on age, sex, and Milan criteria at listing was performed. The modified response evaluation criteria in solid tumors was used to categorize patients as responders or non-responders to pre-transplant LRT based on imaging performed before and after LRT. Overall survival (OS) and recurrence-free survival (RFS) were examined. Results: OS at 3 years post-transplant was 74% for HCC-CCA and 87% for HCC. RFS at 3 years was 74% for HCC-CCA, and 87% for HCC. Among responders to LRT, the 3-year OS was 92% for HCC-CCA and 88% for HCC; among non-responders, 3-year OS was 43% for HCC-CCA and 83% for HCC. Higher 3-year OS was observed among HCC-CCA responders (77%) compared with HCC-CCA non-responders (23%). Conclusions: OS was similarly high among responders to pre-transplant LRT irrespective of tumor type. Radiologic response to LRT could potentially be used to select appropriate HCC-CCA patients for LT if the findings are validated in independent studies.

Although hepatocellular carcinoma (HCC) has become a common indication for liver transplantation (LT), intrahepatic cholangiocarcinoma (ICC) and combined hepatocellular carcinoma–cholangiocarcinoma (cHCC‐CCA) are historically contraindicated due to their aggressive behavior. On the basis of recent experiences, some groups have proposed a clinical trial investigating the role of LT for patients with early cholangiocarcinoma (CCA), defined as a single lesion ≤ 2 cm. The purpose of this study is to assess the clinicopathologic features and outcomes following LT for patients who were initially diagnosed with HCC and subsequently found to have either ICC or cHCC‐CCA on explant. Patients with the diagnosis of primary liver cancer (PLC) after LT from a single center were retrospectively reviewed. Outcomes for patients with early CCA were compared with patients with HCC within Milan criteria (MC). Out of 618 patients transplanted with PLC, 44 patients were found to have CCA on explant. On the basis of preoperative imaging, 12 patients met criteria for early CCA and were compared with 319 patients who had HCC within MC. The 1‐ and 5‐year overall survival for early CCA versus HCC was 63.6% versus 90.0% and 63.6% versus 70.3% (log‐rank, P = 0.25), respectively. Overall recurrence was 33.3% for early CCA versus 11% for HCC. On explant the patients with CCA were more likely understaged with higher tumor grade and vascular invasion. In conclusion, patients with CCA present a diagnostic challenge, which often leads to the finding of more aggressive lesions on explant after LT, higher recurrence rates, and worse post‐LT survival. Careful consideration of this diagnostic conundrum needs to be made before a clinical trial is undertaken. Liver Transplantation 24 634–644 2018 AASLD.

The importance of proteases during apoptosis is becoming increasingly apparent. Because apoptosis contributes to a diverse variety of disease processes, understanding the roles played by proteases and their inhibitors might provide insight into the pathogenesis of these conditions and suggest novel therapeutic strategies. In this review, we discuss the involvement and role of specific proteases, substrates, and protease inhibitors that appear to participate in the apoptotic process.—Patel, T., Gores, G. J., Kaufmann, S. H. The role of proteases during apoptosis. FASEB J. 10, 587‐597 (1996)

Glycodeoxycholate (GDC) induces apoptosis in hepatocytes by a mechanism associated with DNA cleavage by endonucleases. In many models of apoptosis, proteolysis is required prior to DNA cleavage. Our aims were to determine if enhanced proteolysis is a mechanism causing GDC-mediated apoptosis. In cultured rat hepatocytes exposed to 50 microM GDC for 4 h, nonlysosomal proteolysis increased by 65% compared with controls. The serine protease inhibitor N alpha-p-tosyl-L-lysine chloromethyl ketone (TLCK; 100 microM) reduced cell death from apoptosis by 75% after 4 h of treatment with GDC. TLCK also inhibited DNA fragmentation. There was a twofold increase in nuclear serinelike protease activity during GDC-induced apoptosis accompanied by a 2.5-fold reduction in nonnuclear serine protease activity, suggesting translocation of the protease from the cytosol to the nucleus. Zn2+, an inhibitor of apoptosis, also inhibited nonlysosomal proteolysis and nuclear serinelike protease activity. These novel data suggest that nonlysosomal serinelike protease activity contributes to hepatocyte apoptosis. These data may be important in understanding apoptosis in other cell types and in providing insight into the mechanisms of liver injury during cholestasis.

Abstract Background: Mixed hepatocellular cholangiocarcinoma (HCC-CCA) is a rare primary malignancy of the liver which is distinct from hepatocellular carcinoma (HCC) or cholangiocarcinoma. HCC-CCA is presumed to have a poor prognosis and is not recommended for transplantation. The clinical and radiological presentation of HCC-CCA overlaps with HCC; thus, patients with these cancers may be mis-diagnosed as HCC and undergo liver transplantation, with the precise diagnosis ultimately determined on explant pathology. Patients undergoing transplant for presumed HCC receive loco-regional therapy (LRT), such as transarterial chemoembolization and radiofrequency ablation pre-transplant. Our goals were to (1) evaluate pre-transplant response to LRT, as predictors of recurrence and survival after transplant in HCC-CCA, and to (2) compare outcomes of transplant with adjuvant LRT in HCC-CCA and HCC. Methods: A retrospective study of 57 patients with presumed HCC who underwent liver transplantation and had pre-transplant LRT was performed. The study included 19 HCC-CCA cases and 38 HCC cases diagnosed on explant pathology, and individually matched (1:2) on age, sex, and Milan criteria. Response to LRT was determined by MRI performed before and after LRT. The response evaluation criterion in solid tumors (RECIST) was used to categorize treatment responses as “responders” if a patient had a complete or partial response or “non-responders” if a patient had stable or progressive disease. Recurrence rates, recurrence-free survival (RFS), and overall survival (OS) following LRT and transplant were compared between groups using Fisher’s exact tests. Results: The overall 1- and 3-year survival rates were 84% and 74% for HCC-CCA, and 95% and 87% for HCC, respectively. RFS at 1 and 3 years was 79% and 74% for HCC-CCA, and 92% and 87% for HCC (p-values >0.05). For HCC-CCA, one-year OS and RFS in LRT responders were 92% and 83%, whereas for LRT non-responders, OS and RFS were 71% each. In contrast, for HCC, one-year OS and RFS in LRT responders were both 97%, whereas among non-responders, they were 83% and 67%, respectively. At three years, OS and RFS in responders were 92% and 75% for HCC-CCA and 88% and 90% for HCC, respectively; whereas among non-responders, OS and RFS rates were 43% and 57% for HCC-CCA and 83% and 50% for HCC, respectively (all p-value >0.05). Conclusions: Short-term, post-transplant survival was poorer for HCC-CCA than HCC. However, OS among LRT responders for both cancers was similar. Response to LRT predicts favorable RFS in both HCC-CCA and HCC. Among non-responders, recurrence rate and RFS at three years were dismal and similar for both HCC-CCA and HCC, although OS is much lower for HCC-CCA patients. Response to pre-transplant LRT can be used for identifying HCC-CCA patients at high risk of recurrence and poor survival after liver transplantation. Citation Format: Yacob Y. Habboush, Samuel O. Antwi, Lori Chase, Tushar C. Patel. Response to loco-regional therapy as predictors of outcomes after transplantation for mixed hepatocellular cholangiocarcinoma [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 LB-237. doi:10.1158/1538-7445.AM2017-LB-237

Abstract Background: The paucity of effective therapeutic agents for hepatocellular cancer (HCC) underscores the critical need for more effective therapeutic strategies. Recent studies indicate lipid biosynthesis and desaturation is required for HCC survival. Targeting these may prove beneficial because such changes contribute to therapeutic resistance. Stearoyl CoA desaturase (SCD1), a key mediator of fatty acid (FA) biosynthesis and rate-limiting in conversion of saturated fatty acids (SFAs) to mono-unsaturated fatty acids (MUFAs), is upregulated in HCC and many other cancers. As such, we therapeutically targeted a novel lipogenic tumor survival mechanism mediated by SCD1 as a means to combat the chemoresistance associated with HCC. In so doing, we evaluated a novel lead SCD1 inhibitor in HCC. Methods: Paraffin embedded patient HCC tissues were examined for SCD1 expression. Using combined computational and synthetic chemistry approaches, we synthesized four novel specific SCD1 inhibitors with SSI-4 being the lead SCD1 inhibitor. HCC cell lines were examined using proliferation assays for response to SSI-4. IC50 concentrations for blocking SCD1 enzyme activity was determined. Blood half-life and bioavailability of single dose SSI-4 was determined. Mechanisms of action of SCD1 were examined that included Endoplasmic reticulum (ER) stress. In vivo, antitumor activity was determined using HCC patient derived xenograft (PDX) mouse models. Results: We identified elevated SCD1 mRNA and protein in HCCs tissues. SSI-4 dose-dependently inhibits cell proliferation in HCC cell lines with specificity demonstrated by oleic acid (MUFA) co-culture. Single dose oral gavage SSI-4 demonstrated a half-life of ~4 hours and excellent oral bioavailability. SSI-4 was well tolerated with long-term daily dosing. SSI-4 treatment of HCC cells and tumors led to endoplasmic reticulum (ER) stress followed by apoptotic cell death. Single agent SSI-4 demonstrated antitumor activity in HCC PDX mouse models with suppression of ER stress regulated proteins. Conclusions: Targeting a novel lipid metabolic pathway in HCC may provide effective therapy for aggressive HCC. Citation Format: John Alton Copland, Laura A. Marlow, Ilah Bok, James L. Miller, Matsuda Akiko, Yan W. Asmann, Vivekananda Sarangi, Steven R. Alberts, Kabir Mody, Lewis R. Roberts, Mark J. Truty, Tushar C. Patel. Targeting stearoyl CoA desaturase 1 (SCD1) in hepatobilliary carcinoma [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 192. doi:10.1158/1538-7445.AM2017-192

Cholangiocarcinoma (CCA) includes a heterogeneous group of biliary cancers with poor prognosis. Several conditions, such as primary sclerosing cholangitis (PSC), are risk factors. Noninvasive differential diagnosis between intrahepatic CCA and hepatocellular carcinoma (HCC) is sometimes difficult. Accurate noninvasive biomarkers for PSC, CCA, and HCC are not available. In the search for novel biomarkers, serum extracellular vesicles (EV) were isolated from CCA (n = 43), PSC (n = 30), or HCC (n = 29) patients and healthy individuals (control, n = 32); and their protein content was characterized. By using nanoparticle tracking analysis, serum EV concentration was found to be higher in HCC than in all the other groups. Round morphology (by transmission electron microscopy), size (∼180 nm diameter by nanoparticle tracking analysis), and markers (clusters of differentiation 9, 63, and 81 by immunoblot) indicated that most serum EV were exosomes. Proteome profiles (by mass spectrometry) revealed multiple differentially expressed proteins among groups. Several of these proteins showed high diagnostic values with maximum area under the receiver operating characteristic curve of 0.878 for CCA versus control, 0.905 for CCA stage I‐II versus control, 0.789 for PSC versus control, 0.806 for noncirhottic PSC versus control, 0.796 for CCA versus PSC, 0.956 for CCA stage I‐II versus PSC, 0.904 for HCC versus control, and 0.894 for intrahepatic CCA versus HCC. Proteomic analysis of EV derived from CCA human cells in vitro revealed higher abundance of oncogenic proteins compared to EV released by normal human cholangiocytes. Orthotopic implant of CCA human cells in the liver of immunodeficient mice resulted in the release to serum of EV containing some similar human oncogenic proteins. Conclusion : Proteomic signatures found in serum EV of CCA, PSC, and HCC patients show potential usefulness as diagnostic tools. (H epatology 2017;66:1125‐1143).

ABSTRACTBioinformatics tools are imperative for the in depth analysis of heterogeneous high‐throughput data. Most of the software tools are developed by specific laboratories or groups or companies wherein they are designed to perform the required analysis for the group. However, such software tools may fail to capture “what the community needs in a tool”. Here, we describe a novel community‐driven approach to build a comprehensive functional enrichment analysis tool. Using the existing FunRich tool as a template, we invited researchers to request additional features and/or changes. Remarkably, with the enthusiastic participation of the community, we were able to implement 90% of the requested features. FunRich enables plugin for extracellular vesicles wherein users can download and analyse data from Vesiclepedia database. By involving researchers early through community needs software development, we believe that comprehensive analysis tools can be developed in various scientific disciplines.