Hassan M. Shaleh

Brivanib Attenuates Hepatic Fibrosis In Vivo and Stellate Cell Activation In Vitro by Inhibition of FGF, VEGF and PDGF Signaling

Background and Aims Brivanib is a selective inhibitor of vascular endothelial growth factor receptor (VEGFR) and fibroblast growth factor receptor (FGFR) tyrosine kinases, which are both involved in mechanisms of liver fibrosis. We hypothesized that inhibition of VEGFR and FGFR by brivanib would inhibit liver fibrosis. We therefore examined the effect of brivanib on liver fibrosis in three mouse models of fibrosis. Methods In vivo, we induced liver fibrosis by bile duct ligation (BDL), chronic carbon tetrachloride (CCl4), and chronic thioacetamide (TAA) administration. Liver fibrosis was examined by immunohistochemistry and Western immunoblotting. In vitro, we used LX-2 human hepatic stellate cells (HSCs) to assess the effect of brivanib on stellate cell proliferation and activation. Results After in vivo induction with BDL, CCl4, and TAA, mice treated with brivanib showed reduced liver fibrosis and decreased expression of collagen Iα1 and α-smooth muscle actin in the liver. In vitro, brivanib decreased proliferation of HSCs induced by platelet-derived growth factor (PDGF), VEGF, and FGF. Brivanib also decreased stellate cell viability and inhibited PDGFBB-induced phosphorylation of its cognate receptor. Conclusion Brivanib reduces liver fibrosis in three different animal models and decreases human hepatic stellate cell activation. Brivanib may represent a novel therapeutic approach to treatment of liver fibrosis and prevention of liver cancer.

Antitumor effect of FGFR inhibitors on a novel cholangiocarcinoma patient derived xenograft mouse model endogenously expressing an FGFR2-CCDC6 fusion protein

Cholangiocarcinoma is a highly lethal cancer with limited therapeutic options. Recent genomic analysis of cholangiocarcinoma has revealed the presence of fibroblast growth factor receptor 2 (FGFR2) fusion proteins in up to 13% of intrahepatic cholangiocarcinoma (iCCA). FGFR fusions have been identified as a novel oncogenic and druggable target in a number of cancers. In this study, we established a novel cholangiocarcinoma patient derived xenograft (PDX) mouse model bearing an FGFR2-CCDC6 fusion protein from a metastatic lung nodule of an iCCA patient. Using this PDX model, we confirmed the ability of the FGFR inhibitors, ponatinib, dovitinib and BGJ398, to modulate FGFR signaling, inhibit cell proliferation and induce cell apoptosis in cholangiocarcinoma tumors harboring FGFR2 fusions. In addition, BGJ398 appeared to be superior in potency to ponatinib and dovitinib in this model. Our findings provide a strong rationale for the investigation of FGFR inhibitors, particularly BGJ398, as a therapeutic option for cholangiocarcinoma patients harboring FGFR2 fusions.

Antitumor effect of the novel sphingosine kinase 2 inhibitor ABC294640 is enhanced by inhibition of autophagy and by sorafenib in human cholangiocarcinoma cells

Sphingosine kinase 2 (Sphk2) has an oncogenic role in cancer. A recently developed first-in-class Sphk2 specific inhibitor ABC294640 displays antitumor activity in many cancer models. However, the role of Sphk2 and the antitumor activity of its inhibitor ABC294640 are not known in cholangiocarcinoma. We investigated the potential of targeting Sphk2 for the treatment of cholangiocarcinoma. We found that Sphk2 is overexpressed in five established human cholangiocarcinoma cell lines (WITT, HuCCT1, EGI-1, OZ and HuH28) and a new patient-derived cholangiocarcinoma cell line (LIV27) compared to H69 normal cholangiocytes. Inhibition of Sphk2 by ABC294640 inhibited proliferation and induced caspase-dependent apoptosis. Furthermore, we found that ABC294640 inhibited STAT3 phosphorylation, one of the key signaling pathways regulating cholangiocarcinoma cell proliferation and survival. ABC294640 also induced autophagy. Inhibition of autophagy by bafilomycin A1 or chloroquine potentiated ABC294640-induced cytotoxicity and apoptosis. In addition, ABC294640 in combination with sorafenib synergistically inhibited cell proliferation of cholangiocarcinoma cells. Strong decreases in STAT3 phosphorylation were observed in WITT and HuCCT1 cells exposed to the ABC294640 and sorafenib combination. These findings provide novel evidence that Sphk2 may be a rational therapeutic target in cholangiocarcinoma. Combinations of ABC294640 with sorafenib and/or autophagy inhibitors may provide novel strategies for the treatment of cholangiocarcinoma.

Transcriptional Induction of Periostin by a Sulfatase 2–TGFβ1–SMAD Signaling Axis Mediates Tumor Angiogenesis in Hepatocellular Carcinoma

Existing antiangiogenic approaches to treat metastatic hepatocellular carcinoma (HCC) are weakly effectual, prompting further study of tumor angiogenesis in this disease setting. Here, we report a novel role for sulfatase 2 (SULF2) in driving HCC angiogenesis. Sulf2-deficient mice (Sulf2 KO) exhibited resistance to diethylnitrosamine-induced HCC and did not develop metastases like wild-type mice (Sulf2 WT). The smaller and less numerous tumors formed in Sulf2 KO mice exhibited a markedly lower microvascular density. In human HCC cells, SULF2 overexpression increased endothelial proliferation, adhesion, chemotaxis, and tube formation in a paracrine fashion. Mechanistic analyses identified the extracellular matrix protein periostin (POSTN), a ligand of αvβ3/5 integrins, as an effector protein in SULF2-induced angiogenesis. POSTN silencing in HCC cells attenuated SULF2-induced angiogenesis and tumor growth in vivo The TGFβ1/SMAD pathway was identified as a critical signaling axis between SULF2 and upregulation of POSTN transcription. In clinical HCC specimens, elevated levels of SULF2 correlated with increased microvascular density, POSTN levels, and relatively poorer patient survival. Together, our findings define an important axis controlling angiogenesis in HCC and a mechanistic foundation for rational drug development. Cancer Res; 77(3); 632-45. ©2016 AACR.

Abstract C76: Community-wide outreach and screening to reduce hepatitis B, hepatitis C and liver cancer disparities among African immigrants in Minnesota

Background: In Minnesota, the 2012 Cancer Report by the Department of Health reported both the incidence of liver cancer and mortality rates due to liver cancer among Blacks were significantly higher than Caucasians. African immigration to Minnesota is the third highest by percentage of state population in the US. Given that viral hepatitis disproportionately affects sub-Saharan Africans and that these individuals are emigrating from countries where childhood HBV vaccination has only recently been implemented on a national scale, we speculate that this unique immigrant community may be a major contributor to the increased burden of viral hepatitis and liver cancer complications in the state. Limited research exists on the burden of viral hepatitis and hepatocellular carcinoma among African immigrants. Thus, we conducted a prospective community-wide screening to assess the rates of chronic HBV and HCV infections among Somali, Liberian and Kenyan immigrants in Minnesota. Methods: Several African community health centers and organizations in Minnesota were selected for the study. Individuals of Somali, Liberian or Kenyan descent were enrolled in a prospective screening study for chronic HBV and HCV infection. Blood samples were collected and tested for hepatitis B surface antigen (HBsAg), hepatitis B core antibody (HBcAb), hepatitis B surface antibody (HBsAb), and anti-hepatitis C virus antibody (anti-HCV). Follow-up testing, health education, counseling, and referral were provided to participants. Results: 853 participants provided blood specimens. 13.5% of participants had chronic HBV infection while 32.4% had prior HBV exposure with spontaneous viral clearance. 7% of participants had chronic HCV infection. Follow up and linkage to care were provided to participants with chronic hepatitis while preventive advice was provided to those who were negative for both infections. In particular, participants susceptible to HBV were informed about the availability of HBV vaccine in order to protect against future HBV infection. Conclusions: Chronic HBV and HCV are major health problems among recent African immigrants in Minnesota. Community-based screening is an effective way to identify and provide health education and linkage to care for individuals with or at risk for viral hepatitis. Citation Format: Essa A. Mohamed, Nasra H. Giama, Hassan M. Shaleh, Abdul M. Oseini, Hager Ahmed Mohammed, Jessica Cvinar, Ibrahim A. Waaeys, Hamdi A. Ali, Loretta K. Allotey, Lewis R. Roberts. Community-wide outreach and screening to reduce hepatitis B, hepatitis C and liver cancer disparities among African immigrants in Minnesota. [abstract]. In: Proceedings of the Ninth AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2016 Sep 25-28; Fort Lauderdale, FL. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2017;26(2 Suppl):Abstract nr C76.

Abstract A46: A cross-sectional assessment of knowledge, attitudes, and behaviors about viral hepatitis and hepatocellular carcinoma among Kenyan and Liberian immigrants living in Minnesota

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. Spearman9s 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 .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.

Abstract C01: Evaluating knowledge, attitudes, and behaviors about viral hepatitis and hepatocellular carcinoma among recent African immigrants in Minnesota: A community-engaged qualitative study

Background: African immigrants in the US have substantially higher prevalences of viral hepatitis and hepatocellular carcinoma than the general population. In Minnesota, which has the third largest state population of African immigrants in the US, the incidence and mortality for hepatocellular carcinoma among Blacks is 3 times higher than Caucasians (The 2012 Minnesota Department of Health Cancer Report). Most African immigrants are unaware of their risk for hepatocellular carcinoma which contributes to substantial liver health disparities. Limited research exists on the burden of viral hepatitis and hepatocellular carcinoma among African immigrants. Thus, we conducted a pilot study to evaluate the knowledge, attitudes, and behaviors (KAB) of African immigrants related to liver disease. Methods: The study used a community-engaged research framework. The research team consisted of stakeholders from an academic medical center and Ethiopian, Liberian, and Kenyan community-based organizations and faith-based centers. A semi-structured focus group guide was developed using a KAB approach with open-ended questions. Content analysis was used to thematically code the transcribed data. Qualitative analysis software (ATLAS.TI) was used to organize codes and highlight major themes contributing to liver health disparities. Results: We enrolled 63 participants and conducted 9 focus groups (1 in Amharic, 2 in Oromo, and 6 in English) in Rochester and Minneapolis, Minnesota. The mean age was 47±19; 32 participants (51%) were male; the median years lived in the US was 12 years. General knowledge of the modes of transmission of viral hepatitis and of the prevention and development of liver cancer was minimal. Themes related to barriers to viral hepatitis screening and vaccination included perceived cultural stigma and use of traditional remedies. Common sources of general health information included internet, pamphlets, friends, family, spiritual leaders and healthcare professionals. Healthcare professionals are the source for information on screening, prevention, transmission and treatment of viral hepatitis and liver cancer. Most participants sought healthcare at reputable medical institutions. Media sources and community-based events at faith-centers were preferred modes of information dissemination on viral hepatitis and liver cancer screening and prevention. Conclusions: Participants identified several factors contributing to the increased burden of hepatocellular carcinoma in Minnesota including lack of knowledge of disease transmission and progression, cultural stigma/taboos, and lack of preventive care. Culturally and linguistically appropriate interventions are needed to increase awareness, prevention, early detection, and treatment of viral hepatitis and liver cancer among African immigrants in Minnesota. Citation Format: Essa A. Mohamed, Nasra H. Giama, Hassan M. Shaleh, Linda M. Kerandi, Abdul M. Oseini, Hager F. Ahmed Mohammed, Henry M. Kerandi, Dekermue Togbah, Abdiwahab O. Ali, Ibrahim A. Waaeys, Hamdi A. Ali, Safra A. Mohamed, Hawa M. Ali, Joyce E. Balls-Berry, Lewis R. Roberts. Evaluating knowledge, attitudes, and behaviors about viral hepatitis and hepatocellular carcinoma among recent African immigrants in Minnesota: A community-engaged qualitative study. [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 C01.

Sa1709 Antitumor Effect of the Potent FGFR Inhibitor Ponatinib on an FGFR2-Fusion Driven Cholangiocarcinoma Mouse Model

Background: Overcrowding always lead to the shedding of live cells to maintain homeostasis in epithelial cell sheets. Recently, some reports have shown that overcrowded cancer cells can be basally extruded by their neighbors, and then form metastases. However, this interesting phenomenon needs to be further clarified, and the exact mechanisms driving the extrusion of crowded cancer cell sheets remain elusive. We have previously confirmed that BVES, a novel adhesion molecule regulating tight junction formation, could inhibit liver cancer cell extrusion in a simply and skillfully designed 2D cell culture model, as cancer cells are always basally extruded, in this study, we performed a 3D cell culture model to further confirm the inhibition role of BVES in liver cancer cell extrusion. Methods: We designed a 3D cell culture model, after centrifuge, 5×10 6 cells were resuspended by 120μl 10% sucrose solutions, and quickly mixed with equal volume of 0.5% hydrogel solution( BeaverNanoTM ), the cells were then seeded in a Class Bottom Cell Culture Dish(NEST), and allowed to grow for six days. Then, cells were fixed with 4 % paraformaldehyde, incubated with primary antibody and secondary antibody, observed under a confocal microscopy. Extracted cell number were also investigated after enhanced or silenced expression of BVES. RhoA agonist U-46619 and inhibitor C3 enzyme were used to verify the role of RhoA/Rho-kinase pathway in BVES inhibited cancer cell extrusion. Results: Cells successfully grown to form an overcrowded cell mass in the 3D cell culture model, the number of extruded SK-Hep-1 cells, a high metastasis potential cell line, was significantly more than Huh7 cells with low metastasis potential, the normal liver cell line LO2 cells nearly had no cell extruded. Meanwhile, the extruded cells had decreased expression of BVES. Overexpression of BVES inhibited cells extrusion in the 3D cell culture model and increased RhoA activity in SK-Hep-1 cells, while stable knockdown of BVES remarkably promoted cells extrusion and decreased RhoA activity in Huh7 cells. U-46619 increased Huh7 cells extrusion while treated with C3 enzyme significantly diminished cells extrusion. Conclusion: These results suggest that in crowding liver cancer, BVES inactivate RhoA signaling pathway to decrease liver cancer cells extrusion, subsequently may inhibits tumor metastasis. (This study is supported by the National Natural Science Foundation of China NO:81472311 and the Fundamental Research Funds for the Central Universities 2014ZHYX020)