Nellie A. Campbell

Upamostat is an orally available small-molecule serine protease inhibitor that is a highly potent inhibitor of trypsin 1, trypsin 2, trypsin 3 (PRSS1/2/3), and the urokinase-type plasminogen activator (uPA). These enzymes are expressed in many cancers, especially during tissue remodeling and subsequent tumor cell invasion. Opaganib (ABC294640), a novel, orally available small molecule is a selective inhibitor of the phosphorylation of sphingosine to sphingosine-1-phosphate (S-1-P) by sphingosine kinase 2 (SPHK2). Both sphingosine kinase 1 (SPHK1) and SPHK2 are known to regulate the proliferation-inducing compound S-1-P. However, SPHK2 is more critical in cancer pathogenesis. The goal of this project was to investigate the potential antitumor effects of upamostat and opaganib, individually and in combination, on cholangiocarcinoma (CCA) xenografts in nude mice. PAX165, a patient-derived xenograft (PDX) from a surgically resected CCA, expresses substantial levels of SPHK2, PRSS1, PRSS2, and PRSS3. Four groups of 18 mice each were treated with upamostat, opaganib, both, or vehicle. Mouse weights and PAX165 tumor volumes were measured. Tumor volumes in the upamostat, opaganib, and upamostat plus opaganib groups were significantly decreased compared to the control group.

Mixed acinar neuroendocrine carcinoma of the pancreas (MANEC-P) is an extremely rare malignancy with a poor prognosis. However, epidemiological estimates of MANEC-P remain unknown. This study aimed to estimate and compare the incidence, prevalence, and cancer-specific survival (CSS) of MANEC-P in the United States (US). Patients with MANEC-P were identified through the Surveillance, Epidemiology, and End Results (SEER) and National Program of Cancer Registries databases between 2000–2017. The primary outcomes included age-adjusted incidence rate, limited-duration prevalence, and CSS. A total of 630 patients were identified for the incidence analysis and 149 for the prevalence and CSS analyses. The MANEC-P incidence rate was 0.011 per 100,000 individuals, which was the lowest among pancreatic cancer histologic subtypes. The incidence rate was significantly higher in men and Black races and peaked at 75–79 years of age. The incidence rate was the lowest in the midwestern region (0.009) and the highest in the northeastern US (0.013). The 17-year prevalence was 0.00005%, indicating that 189 patients were alive in the United States at the beginning of 2018. The median CSS of MANEC-P was estimated to be 41 (23, 69) months. In conclusion, MANEC-P is very rare, and its incidence rate has been steady in the US over the last two decades. MANEC-P has a poor prognosis and is the 5th leading cause of pancreatic cancer-related death in the US.

Cholangiocarcinoma (CCA) is a highly lethal cancer arising from the biliary tract epithelium. The cancer biology of this neoplasm is not well understood. To date, only a few CCA cell lines have been reported, which were mostly developed from Asian patients. In this study, we report and characterize a new intrahepatic CCA cell line, LIV27, derived from a surgically resected tumor in a 67-year-old Caucasian woman with primary sclerosing cholangitis (PSC). LIV27 cells grow well in collagen-coated flasks or plates with a doubling time of 57.8 h at passage 14. LIV27 cells have high tumorigenicity in nude mice and stain positive for CK7 and CK19, markers that differentiate CCA from hepatocellular carcinoma. Karyotype analysis showed that LIV27 is aneuploid. We established a single-locus short tandem repeat profile for the LIV27 cell line. This newly established cell line will be a useful model for studying the molecular pathogenesis of, and developing novel therapies for, cholangiocarcinoma.

Background: Mixed acinar neuroendocrine carcinoma (MANEC) of the pancreas is an extremely rare histopathologic subtype. MANEC is an amphicrine malignancy composed of at least 25% of acinar cell carcinoma (PACC) and neuroendocrine carcinoma (pNET). No standard systemic treatment is available for MANEC and current recommendations are derived from standard of care for PACC or pNET. Platinum based regimens have been approved for PACC while targeted agents (sunitinib and everolimus) are approved for pNET. This study aimed to investigate the antitumor effect and toxicities of both platinum based and targeted agents on a successfully first described patient derived xenograft (PDX) of metastatic MANEC of the pancreas. Methods: Several generations of PDX from a surgically resected metastatic MANEC of the pancreas was histologically validated. PDX-MANEC tumors were heterotopically implanted into NOD/SCID mice and randomized into 6 groups (4 mice each) as in table 1. The study continued for 3 weeks. Antitumor efficacy was determined based on change in the tumor volume. Toxicity was assessed change in mice weights. Results: Table 1 shows the changes in tumor volume and mouse weight in all study arms compared to controls end point. Only FOLFIRINOX and gemcitabine/cisplatin arms revealed overall decrease in tumor volume lower than starting volume in controls. All arms other than sunitinib, led to decrease in overall tumor volume compared to control tumor volumes over time. All treatment arms led to lower trending mouse weights (toxicities) except sunitinib, however only the everolimus arm had statistical significance. Conclusion: Both platinum-based regimens and everolimus revealed significant tumor control. No synergistic effect observed in sunitinib/everolimus. Preclinical studies are undergoing to investigate other effective and less toxic therapeutics for MANEC. Citation Format: Amro M. Abdelrahman, Jennifer A. Yonkus, Roberto Alva-Ruiz, Jennifer L. Leiting, Nellie A. Campbell, Lewis R. Roberts, Michael L. Kendrick, David M. Nagorney, Sean P. Cleary, Travis E. Grotz, Gregory J. Gores, Jun Yin, Rondell P. Graham, Thorvardur R. Halfdanarson, Rory L. Smoot, Mark J. Truty. Preclinical efficacy of platinum based chemotherapy regimens and targeted therapeutics in the first successful described patient derived xenograft model of mixed acinar neuroendocrine carcinoma of the pancreas [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 413.

Background and Aims: Existing therapeutic approaches to treat cholangiocarcinoma (CCA) have limited effectiveness, prompting further study to develop therapies for CCA. We report a mechanistic role for the heparan sulfate editing enzyme sulfatase 2 (SULF2) in CCA pathogenesis. Approach and Results: In silico analysis revealed elevated SULF2 expression in human CCA samples, occurring partly through gain of SULF2 copy number. We examined the effects of knockdown or overexpression of SULF2 on tumor growth, chemoresistance, and signaling pathway activity in human CCA cell lines in vitro. Up‐regulation of SULF2 in CCA leads to increased platelet‐derived growth factor receptor beta (PDGFRβ)–Yes‐associated protein (YAP) signaling activity, promoting tumor growth and chemotherapy resistance. To explore the utility of targeting SULF2 in the tumor microenvironment for CCA treatment, we tested an anti‐SULF2 mouse monoclonal antibody, 5D5, in a mouse CCA xenograft model. Targeting SULF2 by monoclonal antibody 5D5 inhibited PDGFRβ–YAP signaling and tumor growth in the mouse xenograft model. Conclusions: These results suggest that SULF2 monoclonal antibody 5D5 or related agents may be potentially promising therapeutic agents in CCA.

Background: Upamostat is an orally available small molecule serine protease inhibitor that is a highly potent inhibitor of trypsin 1, trypsin 2 and trypsin 3 (PRSS1/2/3) as well as urokinase-type plasminogen activator (uPA) which are expressed in many cancers and mediate cell migration, invasion and tissue remodeling. Opaganib (ABC294640), a novel, orally available small molecule is a specific inhibitor of sphingosine kinase 2 (SPHK2), which phosphorylates sphingosine to sphingosine-1-phosphate (S-1-P). While proliferation induced by S-1-P is regulated by both sphingosine kinase 1 (SPHK1) and SPHK2, SPHK2 appears to be more involved in cancer. We aimed to investigate the potential antitumor effect of upamostat and opaganib, individually and in combination, on cholangiocarcinoma (CCA) patient derived xenografts (PDX) in nude mice. Methods: PAX165, a PDX from a surgically resected CCA, expresses substantial levels of SPHK2, PRSS1, PRSS2 and PRSS3. 4 groups of 18 mice were treated with either drug or both. Mouse weights and tumor volumes were measured. In addition, experiments were conducted using the chorioallantoic membrane (CAM) of chicken embryos. Results: Table 1 shows the average tumor size for the control, upamostat, opaganib, and upamostat+opaganib groups at the study end point (Day 42). Tumor volumes in the upamostat, opaganib, and upamostat+opagnib groups were significantly decreased compared to the control group. The CAM experiments are ongoing and will be presented at the AACR Annual Meeting. Conclusion: This preclinical study demonstrated that upamostat and opaganib resulted in tumor regression in mice. Body weights of the mice showed no significant inter- or intra- group differences. The combination of upamostat and opaganib treatment showed greater regression compared to either upamostat or opaganib alone. Studies are underway to identify the molecular mechanisms of their interaction. Citation Format: Faizal Z. Asumda, Mohamed A. Hassan, Yo Han Kim, Nellie A. Campbell, Xin Luo, Daniel R. O'Brien, Sarah A. Buhrow, Joel M. Reid, Michael J. Moore, Vered Katz Ben-Yair, Reza Fathi, Mark L. Levitt, Fabrice Lucien-Matteoni, Jennifer L. Leiting, Mark J. Truty, Lewis R. Roberts. Effects of upamostat and opaganib on cholangiocarcinoma patient derived xenografts [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 3078.

Sulfatase 2 (SULF2) is a heparan sulfate editing enzyme that regulates the milieu of growth factors and cytokines involved in a variety of cellular processes. We used a murine model of diet-induced steatohepatitis to assess the effect of SULF2 down-regulation on the development of nonalcoholic steatohepatitis (NASH) and liver fibrosis. Wildtype B6;129 mice (WT) and Sulf2-knockout B6;129P2-SULF2^{Gt(PST111)Byg} mice (Sulf2-KO) were fed a fast food diet (FFD) rich in saturated fats, cholesterol and fructose or a standard chow diet (SC) ad libitum for 9 months. WT mice on FFD showed a 3-fold increase in hepatic SULF2 mRNA expression, and a 2.2-fold increase in hepatic SULF2 protein expression, compared to WT mice on SC. Knockout of Sulf2-led to a significant decrease in diet-mediated weight gain and dyslipidemia compared to WT mice on FFD. Knockout of Sulf2-KO also abrogated diet-induced steatohepatitis and hepatic fibrosis compared to WT mice on FFD. Furthermore, expression levels of the profibrogenic receptors TGFβR2 and PDGFRβ were significantly decreased in Sulf2-KO mice compared to WT mice on FFD. Together, our data suggest that knockout of Sulf2 significantly downregulates dyslipidemia, steatohepatitis and hepatic fibrosis in a diet-induced mouse model of NAFLD, suggesting that targeting of SULF2 signaling may be a potential therapeutic mechanism in NASH.