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The complexity of liver tumorigenesis is underscored by the recently observed anti-oncogenic effects of oncoproteins, although the mechanisms are unclear. Shp2/Ptpn11 is a proto-oncogene in hematopoietic cells and antagonizes the effect of tumor suppressor Pten in leukemogenesis. In contrast, we show here cooperative functions of Shp2 and Pten in suppressing hepatocarcinogenesis. Ablating both Shp2 and Pten in hepatocytes induced early-onset non-alcoholic steatohepatitis (NASH) and promoted genesis of liver tumor-initiating cells likely due to augmented cJun expression/activation and elevated ROS and inflammation in the hepatic microenvironment. Inhibiting cJun partially suppressed NASH-driven liver tumorigenesis without improving NASH. SHP2 and PTEN deficiencies were detected in liver cancer patients with poor prognosis. These data depict a mechanism of hepato-oncogenesis and suggest a potential therapeutic strategy.

Hepatitis B virus (HBV) causes serious health issues worldwide. Despite this, current treatment options for HBV have many drawbacks. Strategies to safely and specifically target HBV replication and survival at the transcriptional level within host cells are needed to combat current drawbacks in treatment. In this study, we designed a novel artificial transcription factor (ATF) with suppressive function to target and bind to the HBV core promoter, a component that plays a central role in the viral life cycle. ATF has attached specifically to the intended target site by using electrophoretic mobility shift assays (EMSA). We tested whether targeting this suppressive ATF had any effect on HBV gene expression by transfection factor, western blotting, and real-time PCR. In the presence of ATF, viral mRNA and DNA levels were significantly decreased within HepG2.2.15 cells compared to control cells. The HBV-derived protein expression of HBV-e antigen (HBeAg) and HBV-c antigen (HBcAg) was also significantly inhibited. These results show that ATF treatment targeting the HBV core protein promoter has an antiviral effect and inhibits HBV infection in host cells. These results further suggest that the design of new artificial transcription factors may be valuable antiviral therapies to treat HBV patients., (© 2020 by the Association of Clinical Scientists, Inc.)

Objective To investigate the protective effect of fisetin (FIS) against hypoxia/reoxygenation (H/R) injury in rat hepatocytes and its mechanism. Methods H/R injury model of BRL-3A cells was established and the cells were pretreated with FIS. Survival rate was detected by CCK-8 assay. Cell apoptosis was measured by flow cytometry. The levels of ALT and AST were determined by microplate assay. The production of TNF-α and IL-1β were detected by ELISA. The mRNA and protein levels of TLR4 and NF-κBp65 were analyzed by quantitative real-time PCR and Western blotting, respectively. Results After subjected to H/R, cell survival rate decreased and the apoptosis level increased. The levels of ALT and AST in cell supernatant were elevated, so were the production of TNF-α and IL-1β. FIS pretreatment increased the cell survival rate and inhibited apoptosis. The levels of ALT, AST and the production of TNF-α and IL-1β were reduced significantly. Moreover, FIS inhibited the increasing expression levels of TLR4 and NF-κBp65 induced by H/R. Conclusion FIS alleviates the hepatocyte injury induced by H/R via modulation of TLR4/NF-κB signaling pathway.

Objective To investigate the roles of tumor-associated macrophages (TAMs) and epithelial growth factor receptor (EGFR)/β-catenin signaling pathway in sorafenib resistance of hepatocellular carcinoma cells. Methods Macrophages were isolated from peripheral blood mononuclear cells (PBMCs) and cultured in the presence of colony-stimulating factor (M-CSF) to obtain TAMs. Phenotypes of TAMs were identified. The level of epithelial growth factor (EGF) secreted by TAMs was detected by ELISA. CCK-8 assay was performed to verify the effects of EGF on HepG2 and SMMC7721 cell proliferation. Transwell TM assay was used to examine the effects of EGF on the invasion and migration ability of HepG2 and SMMC7721 cells. TAMs and hepatocellular carcinoma cells were co-cultured to study the downstream signaling pathways. Sorafenib-resistant HepG2 and SMMC7721 strains (R-HepG2 and R-SMMC7721 cells) were prepared and then subjected to Western blotting and immunohistochemistry to examine the expression levels of β-catenin and EGFR. Results TAMs we prepared were confirmed. Compared with HepG2 and SMMC7721 cells, R-HepG2 and R-SMMC7721 showed enhanced proliferation, invasion and migration abilities. The growth rates of sorafenib-resistant cell lines after co-cultured with TAMs were significantly higher than those of the controls. The protein expressions of β-catenin and EGFR in sorafenib-resistant cells and hepatocellular carcinoma tissues were higher than those in the controls. Conclusion TAMs and EGFR/β-catenin signaling pathway promote the proliferation, invasion and migration of sorafenib resistance of hepatocellular carcinoma cells.

Objective To study the effect of microRNA-21 (miR-21) on hypoxia/reoxygenation (H/R)-treated primary hepatocytes from C57BL/6J mice and analyze its possible molecular mechanism. Methods The H/R model of primary hepatocytes was established and the expression of miR-21 was detected by the quantitative real-time PCR. Western blotting was used to detect protein expression levels of phosphatase and tension homology deleted on chromosome 10 (PTEN), phosphorylated AKT (p-AKT), Bcl-2 and Bax. Flow cytometry was performed to observe the hepatocyte apoptosis. Results The expression of miR-21 in primary hepatocytes decreased after H/R injury. After transfected with exogenous miR-21 mimics, the expression of PTEN decreased, while the expressions of p-AKT and Bcl-2 and the ratio of Bcl-2/Bax increased in hepatocytes; the apoptotic level of hepatocytes was downregulated. The inhibition of AKT phosphorylation could downregulate the expression of Bcl-2 and the ratio of Bcl-2/Bax, and upregulate the level of hepatocyte apoptosis. Conclusion The miR-21 can alleviate the hepatocyte apoptosis by inhibiting the PTEN/PI3K/AKT signaling pathway in the process of H/R.