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Background & Aims: The biological relevance and regulation mechanism of aberrant miR-223 expression in human hepatocellular carcinoma (HCC) remain unknown. Our aim was to investigate miR-223 regulation in HCC. Methods: miR-223 and integrin αV dysregulation were verified in 57 HCC specimens. Immunohistochemical analysis of integrin αV and sulfatide levels was performed on another cohort of 103 HCC samples. Epigenetic analysis was used to explore the effect of sulfatide on miR-223 transcription. Orthotopic growth, and intrahepatic and pulmonary metastasis of tumors derived from SMMC-7721 cells expressing miR-223 or cerebroside sulfotransferase were monitored in mice. Results: miR-223 was reduced in HCC specimens and highly metastatic cell lines. Enhanced miR-223 expression had a negative effect on integrin αV-mediated cell migration. In vivo assays of metastasis in an orthotopically implanted model demonstrated that miR-223 effectively inhibited HCC metastasis. Further analysis demonstrated that integrin αV is negatively regulated by miR-223. Moreover, the integrin αV subunit was significantly positively correlated with highly expressed sulfatide in 103 HCC specimens. Intriguingly, miR-223 expression was suppressed by sulfatide in HCC in association with reduced recruitment of acetylated histone H3 and C/EBPα to the pre-miR-223 gene promoter, where monocytic leukemia zinc finger (MOZ) protein, a MYST-type histone acetyltransferase, lost its attachment. The expression of histone deacetylases, HDAC9 and HDAC10, were greatly stimulated by sulfatide and their recruitment to miR-223 gene promoter was enhanced. Conclusions: Downregulation of miR-223 in HCC is associated with the epigenetic regulation by highly expressed sulfatide and involved in tumor metastasis. [Copyright &y& Elsevier]

Highlights • IL-2 promotes sorafenib-mediated apoptosis in Huh7 cells. • IL-2 in combination with sorafenib interrupts mitochondrial metabolism. • Mitochondrial fragmentation is augmented by IL-2 in the presence of sorafenib. Abstract Sorafenib is a standard targeted drug used to treat hepatocellular carcinoma (HCC). Notably, cytokine has been found to further enhance the therapeutic effectiveness of the targeted drug. Thereby, the aim of this study is to verify whether cytokine IL-2 could increase the anti-cancer effects of sorafenib on liver cancer in vitro. Huh7 cells were used in the present study and the cell apoptosis and migration were determined in response to sorafenib treatment. Then, siRNA and pathway blocker were used to determine the molecular mechanisms by which IL-2 enhance the therapeutic effectiveness of Huh7 liver cancer cell in vitro. The data in our study illustrated that sorafenib treatment induced apoptosis in Huh7 liver cancer cell in vitro, an effect that was accompanied with a drop in cell proliferation and migration. Biological investigation demonstrated that IL-2 supplementation further augmented the pro-apoptotic effects of sorafenib in vitro. At the molecular levels, the combination of IL-2 and sorafenib impaired mitochondrial respiratory function, reduced mitochondrial potential, promoted mitochondrial ROS overloading and activated mitochondrial apoptotic pathway. Meanwhile, we found that IL-2 supplementation induced mitochondrial stress via activating mitochondrial fragmentation in a manner dependent on MAPK-JNK signalling pathway and TAZ protein. Blockade of the JNK signalling pathway and/or knockdown of TAZ could abrogate the inhibitor effects of IL-2/sorafenib on liver cancer survival, growth and mobility. Collectively, these data indicated that IL-2 supplementation could further augment the anti-cancer effectiveness of sorafenib via activating mitochondrial fragmentation in a manner dependent on MAPK-JNK signalling pathway and TAZ protein. This finding identifies mitochondrial stress and the JNK-Hippo pathway as the potential targets to treat liver cancer. [ABSTRACT FROM AUTHOR]

Tumor-associated macrophages (TAMs) are well accepted and the pathological role of macrophages in hematopoietic malignancies have been proposed. Hepatomegaly is frequently observed in T cell acute lymphoblastic leukemia (T-ALL) patients with poor prognosis. However, the role of leukemia-associated macrophages (LAMs) in hepatic microenvironment remains unclear. Here, the characteristics of hepatic LAMs (H-LAMs) were studied in Notch1 induced T-ALL model. Increase in proportion and absolute counts of H-LAMs was detected with infiltration of inflammatory cells. Furthermore, H-LAMs exhibited a more M1-like phenotype distinct from that of TAMs in hepatocellular carcinoma and LAMs from BM or spleen in leukemia. Moreover, H-LAMs expressed increased level of cytokines in charge of recruiting inflammatory cells, which contributed to pro-inflammatory hepatic microenvironment. [ABSTRACT FROM AUTHOR]

Large tumor suppressor 2 (LATS2), an important mediator of the cell apoptotic response pathway, has been linked to the progression of several cancers. Here, we described the molecular feature of LATS2 as a novel antitumor factor in liver cancer cells in vitro. Western blotting was used to detect the expression of LATS2 and its downstream factors. ELISA, immunofluorescence, and flow cytometry were used to evaluate the alterations of mitochondrial function in response to LATS2 overexpression. Adenovirus-loaded LATS2 and siRNA against DRP1 were transfected into liver cancer cells to overexpress LATS2 and knockdown DRP1 expression, respectively. The results of the present study demonstrated that overexpression of LATS2 was closely associated with more liver cancer cell death. Mechanistically, LATS2 overexpression increased the expression of DRP1, and DRP1 elevated mitochondrial division, an effect that was accompanied by mitochondrial dysfunction, including mitochondrial membrane potential reduction, mitochondrial respiratory complex downregulation, mitochondrial cyt-c release into the nucleus and mitochondrial oxidative injury. Moreover, LATS2 overexpression also initiated mitochondrial apoptosis, and this process was highly dependent on DRP1-related mitochondrial division. Molecular investigations demonstrated that LATS2 modulated DRP1 expression via the Wnt/β-catenin pathway. Inhibition of the Wnt/β-catenin pathway pregented LATS2-mediated DRP1 upregulation, ultimately sustaining mitochondrial function and cell viability in the presence of LATS2 overexpression. Altogether, the above data identify LATS2-Wnt/β-catenin/DRP1/mitochondrial division as a novel anticancer signaling pathway promoting cancer cell death, which might be an attractive therapeutic target for the treatment of hepatocellular carcinoma. [ABSTRACT FROM AUTHOR]

Purpose To investigate the role of miR-20a in hepatocellular carcinoma (HCC) cell radioresistance, which may reveal potential strategies to improve treatment. Methods and Materials The expression of miR-20a and PTEN were detected in HCC cell lines and paired primary tissues by quantitative real-time polymerase chain reaction. Cell radiation combined with colony formation assays was administrated to discover the effect of miR-20a on radiosensitivity. Bioinformatics prediction and luciferase assay were used to identify the target of miR-20a . The phosphatidylinositol 3-kinase inhibitor LY294002 was used to inhibit phosphorylation of Akt , to verify whether miR-20a affects HCC cell radioresistance through activating the PTEN/PI3K/Akt pathway. Results MiR-20a levels were increased in HCC cell lines and tissues, whereas PTEN was inversely correlated with it. Overexpression of miR-20a in Bel-7402 and SMMC-7721 cells enhances their resistance to the effect of ionizing radiation, and the inhibition of miR-20a in HCCLM3 and QGY-7701 cells sensitizes them to it. PTEN was identified as a direct functional target of miR-20a for the induction of radioresistance. Overexpression of miR-20a activated the PTEN/PI3K/Akt signaling pathway. Additionally, the kinase inhibitor LY294002 could reverse the effect of miR-20a –induced radioresistance. Conclusion MiR-20a induces HCC cell radioresistance by activating the PTEN/PI3K/Akt pathway, which suggests that miR-20a/PTEN/PI3K/Akt might represent a target of investigation for developing effective therapeutic strategies against HCC. [ABSTRACT FROM AUTHOR]