Roberts, Lewis R

Abstract Background: Hepatocellular Carcinoma (HCC) is the 6th most common cancer and the 2nd leading cause of cancer-related mortality in the world. Sub-Saharan Africa and Eastern Asia are regions endemic for viral hepatitis, accounting for 80% of all HCC cases worldwide. A recent hospital-based study assessing the frequency of hepatitis B (HBV), hepatitis C (HCV), and HCC among Somali immigrants seen at Mayo Clinic determined the adjusted frequency for HBsAg positivity was 10-fold higher and anti-HCV positivity was 3-fold higher as compared to non-Somali residents of Olmsted County, Minnesota. Furthermore, HCV infection was identified as the leading contributor to HCC development among Somalis. The overall goal of this study is to determine the risk factors, surveillance, treatment options, and outcomes of Somalis with HCC seen at Mayo Clinic. Methods: The Mayo Clinic Unified Data Platform Advanced Cohort Explorer (ACE) query tool was used to identify Somali patients seen at Mayo Clinic from March 1, 1998 to March 31, 2015. Clinical notes were searched in ACE using conjunction and disjunction combinations: the terms Somali, Somalia or Somalian were linked with the terms HCC, Hepatocellular Carcinoma or Liver Cancer. Diagnosis was validated using histopathology and/or imaging reports from the electronic medical record (EMR). To confirm the ethnicity of identified patients, names were screened by author HMA who is of Somali heritage. Variables abstracted from the EMR include demographics, etiology of HCC, diagnosis date, date of death or last contact, Child-Turcotte-Pugh class, Barcelona Clinic Liver Cancer (BCLC) stage, comorbid conditions, initial and subsequent treatments, HCC surveillance, cirrhosis and other malignancies. Results: 54 Somali patients diagnosed with HCC were seen at Mayo Clinic from March 1, 1998 to March 31, 2015. The mean age was 63±16.3 and 36 (67%) individuals were male. Thirty-eight (70%) of the 54 HCC patients had HCV, 14 (26%) had HBV, 1 (2%) had non-alcoholic steatohepatitis (NASH), and 1 (2%) had unknown etiology for HCC. Of those with known HCV genotypes, the most common were genotype 4 (45%) and 3 (35%). At the time of HCC diagnosis, 16 (32%) presented with BCLC stage A, 5 (10%) with stage B, 17 (34%) with stage C, and 12 (24%) with stage D. Of the 54 patients, 43 (80%) had cirrhosis, 15 (28%) had vascular invasion, and 10 (19%) had metastatic HCC. Regarding treatment, 12 (22%) patients received curative treatment while 42 (78%) received palliative treatment. Orthotopic liver transplantation (OLT) was received by 3 (6%) of Somali patients compared to 19% of non-Somali HCC patients seen at Mayo Clinic between 2007 and 2009. HCC was detected during surveillance in 11 (20%) Somali HCC patients; of the 11, 2 (4%) received semiannual surveillance. Conclusions: These findings provide a starting point to address liver cancer disparities among Somalis. HCV genotype 4 was most commonly associated with HCC development among the study population. Due to low surveillance rates, more Somalis presented with end-stage liver disease. Furthermore, advanced stage HCC was disproportionately found among Somalis compared to the general North American population. A recent study demonstrated that 11% of North American HCC patients seen at 4 major medical centers presented with stage D. By contrast, our study found 25% of Somalis had Stage D HCC. As a result, Somalis are more likely to receive palliative rather than curative treatments. Improving the identification of individuals with chronic HBV or HCV who are at increased risk for HCC and implementing more comprehensive HCC surveillance is likely to reduce the burden of HCC among this population. Citation Format: Hawa M. Ali, Nasra H. Giama, Hager Ahmed Mohammed, Essa A. Mohamed, Ju Dong Yang, Abdirashid M. Shire, Lewis R. Roberts. Hepatocellular carcinoma characteristics and outcomes among Somali immigrants. [abstract]. In: Proceedings of the Eighth AACR Conference on The Science of Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; Nov 13-16, 2015; Atlanta, GA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2016;25(3 Suppl):Abstract nr B64.

Abstract Background: The rising incidence of hepatocellular carcinoma in the US is partly due to increased immigration from sub-Saharan Africa. Viral hepatitis is prevalent in sub-Saharan Africa, resulting in ~20% of all hepatocellular carcinoma cases worldwide. Community-based education and screening efforts aimed at identifying viral hepatitis cases among African immigrants will likely reduce the burden of hepatocellular carcinoma. Aim: To determine the knowledge, attitudes and behaviors (KAB) of Liberian and Kenyan immigrants residing in Minnesota about hepatitis B virus and hepatitis C virus screening, vaccination, acquisition, and disease management. Methods: A community-engaged research framework was used for the development of this cross-sectional study. The team created a survey using validated items designed to assess the KAB of viral hepatitis measured on a 1 to 20 scale with 1 being low and 20 being high. Using community-engaged methodology, participants who were ≥18 years of age and self-identified either as Liberian and Kenyan were recruited from churches, community centers, and community events. The survey was administered between June 2014 and February 2015. Spearman's rho correlation was used to identify associations among scores while the Mann-Whitney U-test was used for comparisons between Liberians and Kenyans. Results: Of 80 distributed surveys, 73 were returned, achieving a response rate of 91%. Respondents were 50 (64%) Liberians and 23 (29%) Kenyans; 42 (54%) were female; the mean age was 42 years (range 18-90); most were college educated (57%) and had health insurance (83%). 55% reported previous screening for hepatitis B, 51% had completed hepatitis B vaccination and 38% reported being screened for hepatitis C. Mean scores ± SD were 4.6±2.8 for knowledge, 4.7±1.0 for attitude, and 4.2±1.9 for behavior, resulting in poor knowledge and adequate attitude and behavioral levels. Significant and positive linear correlation was observed between attitude and behavior (r=.385, p<.001), while there were no significant correlations between knowledge and attitude (r=-.115, p=.33) or knowledge and behavior (r=-.11, p=.36). When Liberians and Kenyans were compared, knowledge was higher in Liberians (6.2±1.9 vs1.5±1.0; p<.001); there were no significant differences observed in attitude or behavior scores (p>.05 for both). Conclusions: There is lack of awareness among African immigrants of the health risks associated with viral hepatitis which contributes to disparities in healthcare seeking behaviors. It is important to implement comprehensive education and screening programs on viral hepatitis in these communities in order to reduce the burden of viral hepatitis and hepatocellular carcinoma development. Citation Format: Hassan M. Shaleh, Nasra H. Giama, Essa A. Mohamed, Hager F. Ahmed Mohammed, Linda M. Kerandi, Abdul M. Oseini, Abdiwahab O. Ali, Ibrahim A. Waaeys, Jonggi Choi, Henry M. Kerandi, Safra A. Mohamed, Hamdi A. Ali, Hawa M. Ali, Joyce E. Balls-Berry, Lewis R. Roberts. A cross-sectional assessment of knowledge, attitudes, and behaviors about viral hepatitis and hepatocellular carcinoma among Kenyan and Liberian immigrants living in Minnesota. [abstract]. In: Proceedings of the Eighth AACR Conference on The Science of Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; Nov 13-16, 2015; Atlanta, GA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2016;25(3 Suppl):Abstract nr A46.

Purpose The inclusion of metformin in the treatment arms of cancer clinical trials is based on improved survival that has been demonstrated in retrospective epidemiologic studies; however, unintended biases may exist when analysis is performed by using a conventional Cox proportional hazards regression model with dichotomous ever/never categorization. We examined the impact of metformin exposure definitions, analytical methods, and patient selection on the estimated effect size of metformin exposure on survival in a large cohort of patients with pancreatic ductal adenocarcinoma (PDAC). Patients and Methods Of newly diagnosed patients with PDAC with diabetes, 980 were retrospectively included, and exposure to metformin documented. Median survival was assessed by using Kaplan-Meier and log-rank methods. Hazard ratios (HR) and 95% CIs were computed to compare time-varying covariate analysis with conventional Cox proportional hazards regression analysis. Results Median survival of metformin users versus nonusers was 9.9 versus 8.9 months, respectively. By the time-varying covariate analysis, metformin use was not statistically significantly associated with improved survival (HR, 0.93; 95% CI, 0.81 to1.07; P = .28). There was no evidence of benefit in the subset of patients who were naïve to metformin at the time of PDAC diagnosis (most representative of patients enrolled in clinical trials; HR, 1.01; 95% CI, 0.80 to 1.30; P = .89); however, when the analysis was performed by using the conventional Cox model, an artificial survival benefit of metformin was detected (HR, 0.88; 95% CI, 0.77 to 1.01; P = .08), which suggested biased results from the conventional Cox analysis. Conclusion Our findings did not suggest the benefit of metformin use after patients are diagnosed with PDAC. We highlight the importance of patient selection and appropriate statistical analytical methods when studying medication exposure and cancer survival.

Whether aspirin use is protective against cholangiocarcinoma (CCA) remains unclear. We determined the association between aspirin use and other risk factors for each CCA subtype individually. In a hospital‐based case‐control study, 2395 CCA cases (1169 intrahepatic, 995 perihilar, and 231 distal) seen at the Mayo Clinic, Rochester, MN, from 2000 through 2014 were enrolled. Controls selected from the Mayo Clinic Biobank were matched two to one with cases by age, sex, race, and residence (n = 4769). Associations between aspirin use, other risk factors, and CCA risk were determined. Aspirin was used by 591 (24.7%) CCA cases and 2129 (44.6%) controls. There was a significant inverse association of aspirin use with all CCA subtypes, with adjusted odds ratios (AORs) of 0.35 (95% confidence interval [CI], 0.29‐0.42), 0.34 (95% CI 0.27‐0.42), and 0.29 (95% CI 0.19‐0.44) for intrahepatic, perihilar, and distal CCA, respectively (P < 0.001 for all). Primary sclerosing cholangitis was more strongly associated with perihilar (AOR = 453, 95% CI 104‐999) than intrahepatic (AOR = 93.4, 95% CI 27.1‐322) or distal (AOR = 34.0, 95% CI 3.6‐323) CCA, whereas diabetes was more associated with distal (AOR = 4.2, 95% CI 2.5‐7.0) than perihilar (AOR = 2.9, 95% CI 2.2‐3.8) or intrahepatic (AOR = 2.5, 95% CI 2.0‐3.2) CCA. Cirrhosis not related to primary sclerosing cholangitis was associated with both intrahepatic and perihilar CCA, with similar AORs of 14. Isolated inflammatory bowel disease without primary sclerosing cholangitis was not associated with any CCA subtype. Conclusions: Aspirin use was significantly associated with a 2.7‐fold to 3.6‐fold decreased risk for the three CCA subtypes; our study demonstrates that individual risk factors confer risk of different CCA subtypes to different extents. (Hepatology 2016;64:785‐796)

The hypoxia‐inducible factor (HIF), HIF‐1, is a central regulator of the response to low oxygen or inflammatory stress and plays an essential role in survival and function of immune cells. However, the mechanisms regulating nonhypoxic induction of HIF‐1 remain unclear. Here, we assess the impact of germline heterozygosity of a novel, oxygen‐independent ubiquitin ligase for HIF‐1α: hypoxia‐associated factor (HAF; encoded by SART1). SART1−/− mice were embryonic lethal, whereas male SART1+/− mice spontaneously recapitulated key features of nonalcoholic steatohepatitis (NASH)‐driven hepatocellular carcinoma (HCC), including steatosis, fibrosis, and inflammatory cytokine production. Male, but not female, SART1+/− mice showed significant up‐regulation of HIF‐1α in circulating and liver‐infiltrating immune cells, but not in hepatocytes, before development of malignancy. Additionally, Kupffer cells derived from male, but not female, SART1+/− mice produced increased levels of the HIF‐1‐dependent chemokine, regulated on activation, normal T‐cell expressed and secreted (RANTES), compared to wild type. This was associated with increased liver‐neutrophilic infiltration, whereas infiltration of lymphocytes and macrophages were not significantly different. Neutralization of circulating RANTES decreased liver neutrophilic infiltration and attenuated HCC tumor initiation/growth in SART1+/− mice. Conclusion: This work establishes a new tumor‐suppressor role for HAF in immune cell function by preventing inappropriate HIF‐1 activation in male mice and identifies RANTES as a novel therapeutic target for NASH and NASH‐driven HCC. (Hepatology 2016;63:1576‐1591)

The large diversity and volume of extracellular RNA (exRNA) data that will form the basis of the exRNA Atlas generated by the Extracellular RNA Communication Consortium pose a substantial data integration challenge. We here present the strategy that is being implemented by the exRNA Data Management and Resource Repository, which employs metadata, biomedical ontologies and Linked Data technologies, such as Resource Description Framework to integrate a diverse set of exRNA profiles into an exRNA Atlas and enable integrative exRNA analysis. We focus on the following three specific data integration tasks: (a) selection of samples from a virtual biorepository for exRNA profiling and for inclusion in the exRNA Atlas; (b) retrieval of a data slice from the exRNA Atlas for integrative analysis and (c) interpretation of exRNA analysis results in the context of pathways and networks. As exRNA profiling gains wide adoption in the research community, we anticipate that the strategies discussed here will increasingly be required to enable data reuse and to facilitate integrative analysis of exRNA data.

AbstractGenetic risk factors for cholangiocarcinoma (CCA) remain poorly understood. We assessed the effect of single‐nucleotide polymorphisms (SNPs) of genes modulating inflammation or carcinogenesis on CCA risk and survival. We conducted a case‐control, candidate gene association study of 370 CCA patients and 740 age‐, sex‐, and residential area‐matched healthy controls. Eighteen functional or putatively functional SNPs in nine genes were genotyped. The log‐additive genotype effects of SNPs on CCA risk and survival were determined using logistic regression and the log‐rank test, respectively. Initial analysis identified significant associations between SNP rs2143417 and rs689466 in cyclooxygenase 2 (COX‐2) and CCA risk, after adjusting for multiple comparisons (cutoff of P = 0.0028). However, these findings were not replicated in another independent cohort of 212 CCA cases and 424 matched controls. No significant association was found between any SNP and survival of CCA patients. Although COX‐2 has been shown to contribute to cholangiocarcinogenesis, the COX‐2 SNPs tested were not associated with risk of CCA. This study shows a lack of association between variants of genes related to inflammation and carcinogenesis and CCA risk and survival. Other factors than these genetic variants may play more important roles in CCA risk and survival.

Abstract Purpose: Methylated DNA markers can discriminate upper from lower GI neoplasms (Gastroenterology 2013;144(5):S84). It is unknown if organ-specific molecular prediction of GI tumor site can be achieved. Experimental design: An unbiased search for neoplasm markers at each major GI organ site was conducted by reduced representation bisulfite sequencing. Top marker candidates were then blindly validated by methylation specific PCR on independent tissue DNA samples from normal mucosa [17 esophagus (E), 13 stomach (S), 33 pancreas (P), 35 bile duct/liver (BD), 21 colorectal (CR)] and neoplasia [42 E, 43 S, 36 P, 48 BD, 97 CR]. Recursive partitioning (rPart) trees modeled all stepwise combinations of single markers to classify controls vs neoplasms and then neoplasms by site (CR, gastroesophageal or pancreaticobiliary). A 2nd model was designed from tissue data for blinded clinical piloting on 42 independent plasma DNA samples (14 normal and 28 cancers (14 P, 14 CR). Results: From the top 100 markers, 95 were validated and used for rPart modeling. A 3- marker panel (chr12.133484978-5047, BMP3, chr11.123301058-255) was selected for the universal detection of GI neoplasms, as it classified neoplasms and control tissues with 95% accuracy. Two markers (chr7.25896389-501, QKI) then assigned lower vs upper GI neoplasms with 94% accuracy. Finally, 3 markers (PDGFD, ELOVL2, PCBP3) called pancreaticobiliary vs gastroesophageal neoplasms with 94% accuracy. All 8 markers applied in a single model (Table) accurately predicted control vs tumor by site [88% (p &lt;0.0001)]. In plasma, a 2-marker panel (BMP3, QKI) was 78% accurate in assigning patients to cancer or control groups (p&lt;0.0009) and 83% accurate in assigning cancer origin to CR or P sites (p&lt;0.0001). Predicted by ModelTissue SourceControlsColorectal neoplasiaPancreatico-biliary cancerGastro-esophageal neoplasiaControls1169102Colorectal neoplasia18617Pancreatico-biliary cancer10654Gastro-esophageal neoplasia12872 Conclusion: Panels of methylated DNA markers were identified for both universal detection of GI neoplasia and accurate prediction of tumor site. Pilot testing of these markers in plasma supports potential clinical feasibility. Citation Format: John B. Kisiel, William R. Taylor, Tracy C. Yab, Hassan M. Ghoz, Patrick H. Foote, Mary E. Devens, Douglas W. Mahoney, Thomas C. Smyrk, Lisa A. Boardman, Gloria M. Petersen, Navtej S. Buttar, Lewis R. Roberts, Graham P. Lidgard, David A. Ahlquist. Accurate site prediction of gastrointestinal cancer by novel methylated DNA markers: Discovery & validation. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 4252. doi:10.1158/1538-7445.AM2015-4252