No abstract

The global burden of hepatocellular carcinoma (HCC), one of the frequent causes of cancer-related deaths worldwide, is rapidly increasing partly due to the limited treatment options available for this disease and recurrence due to therapy resistance. Immune checkpoint inhibitors that are proved to be beneficial in the treatment of advanced melanoma and other cancer types are currently in clinical trials in HCC. These ongoing trials are testing the efficacy and safety of a few select checkpoints in HCC. Similar to observations in other cancers, these immune checkpoint blockade treatments as monotherapy may benefit only a fraction of HCC patients. Studies that assess the prevalence and distribution of other immune checkpoints/modulatory molecules in HCC have been limited. Moreover, robust predictors to identify which HCC patients will respond to immunotherapy are currently lacking. The objective of this study is to perform a comprehensive evaluation on different immune modulators as predictive biomarkers to monitor HCC patients at high risk for poor prognosis. We screened publically available HCC patient databases for the expression of previously well described immune checkpoint regulators and evaluated the usefulness of these immune modulators to predict high risk, patient overall survival and recurrence. We also identified the immune modulators that synergized with known immune evasion molecules programmed death receptor ligand-1 (PD-L1), programmed cell death protein-1 (PD-1), and cytotoxic T lymphocyte-associated antigen-4 (CTLA-4) and correlated with worse patient outcomes. We evaluated the association between the expression of epithelial-to-mesenchymal transition (EMT) markers and PD-L1 in HCC patient tumors. We also examined the relationship of tumor mutational burden with HCC patient survival. Notably, expression of immune modulators B7-H4, PD-L2, TIM-3, and VISTA were independently associated with worse prognosis, while B7-H4, CD73, and VISTA predicted low recurrence-free survival. Moreover, the prognosis of patients expressing high PD-L1 with high B7-H4, TIM-3, VISTA, CD73, and PD-L2 expression was significantly worse. Interestingly, PD-L1 expression in HCC patients in the high-risk group was closely associated with EMT marker expression and prognosticates poor survival. In HCC patients, high tumor mutational burden (TMB) predicted worse patient outcomes than those with low TMB.

Extrahepatic biliary atresia is a severe neonatal liver disease resulting from a sclerosing cholangiopathy of unknown etiology. Although biliary obstruction may be surgically corrected by a "Kasai" hepatoportoenterostomy , most patients still develop progressive hepatic fibrosis , although the source of increased collagen deposition is unclear. This study examined the role of hepatic stellate cells (HSCs) and assessed the source of transforming growth factor-␤ (TGF-␤) production in hepatic fibrogenesis in patients with biliary atresia. Liver biopsies from 18 biliary atresia patients (including 5 pre-and post-Kasai) were subjected to immunohistochemistry for ␣-smooth muscle actin and in situ hybridization for either procollagen ␣ 1 (I) mRNA or TGF-␤ 1 mRNA. Sections were also subjected to immunohistochemistry for active TGF-␤ 1 protein. The role of Kupffer cells in TGF-␤ 1 production was assessed by immunohistochemistry for CD68. Procollagen ␣ 1 (I) mRNA was colocalized to ␣-smooth muscle actin-positive HSCs within the region of increased collagen protein deposition in fibrotic septa and surrounding hyperplastic bile ducts. The number of activated HSCs was decreased in only one post-Kasai biopsy. TGF-␤ 1 mRNA expression was demonstrated in bile duct epithelial cells and activated HSCs and in hepatocytes in close proximity to fibrotic septa. Active TGF-␤ 1 protein was demonstrated in bile duct epithelial cells and activated HSCs. This study provides evidence that activated HSCs are responsible for increased collagen production in patients with biliary atresia and therefore play a definitive role in the fibrogenic process. We have also shown that bile duct epithelial cells , HSCs , and hepatocytes are all involved in the production of the profibrogenic cytokine , TGF-␤ 1 . (Am J Pathol 1998, 153:527-535)Extrahepatic biliary atresia is a progressive, sclerosing, inflammatory process in neonates, causing atresia of all or part of the extrahepatic biliary system and rapidly extending to involve the major intrahepatic biliary ducts.