Identification of m6A modification patterns and RBM15 mediated macrophage phagocytosis in pancreatic cancer: An integrative analysis.

Pancreatic cancer (PC) responds weakly to conventional immunotherapy. RNA N6-methyladenosine (m6A) modification has an essential role in the immune response, while its potential role in PC tumor microenvironment (TME) immune cell infiltration remains unknown. In this study, we thoroughly assessed the m6A modification patterns of 472 PC samples using 19 m6A regulators, and we systematically correlated these modification patterns with TME immune cell infiltration characteristics. We also created the m6Ascore and evaluated the m6A modification patterns of individual tumors, identified three different m6A modification patterns, and explored the role of the important m6A "writer" RBM15 in the regulation of macrophage function in PC. Two independent PC cohorts confirmed that patients with higher m6Ascore showed significant survival benefit. We verified that knockdown of RBM15 has the ability to inhibit PC growth and to promote macrophage infiltration and enhance phagocytosis of PC cells by macrophages. In conclusion, m6A modifications play a non-negligible role in the formation of TME diversity and complexity in PC. We reveal that inhibition of RBM15 suppresses PC development and modulates macrophage phagocytosis, and provide a more effective immunotherapeutic strategy for PC.

HSP4 triggers epithelial-mesenchymal transition and promotes motility capacities of hepatocellular carcinoma cells via activating AKT.

BACKGROUND AND AIMS: Heat shock factor (HSF4) plays a vital role in carcinogenesis and tumour progression. However, its clinical significance implications in hepatocellular carcinoma (HCC) remained elusive. METHODS: RT-PCR and western blot were used to detect the HSF4 expression levels in HCC cells and tissues. Immunohistochemistry staining was performed on a tissue microarray containing 104 HCC patients received radical resection. In vitro effects of HSF4 on proliferation, migration and invasion were determined by colony formation and transwell assays in HCCLM3, Huh7, MHCC97L and SMMC7721 cells. Epithelial-mesenchymal transition (EMT) was identified by RT-PCR, WB and immunofluorescence in HCCLM3 and MHCC97L cells. AKT pathway activation was detected by WB and dual luciferase report system in HCCLM3 and MHCC97L cells. RESULTS: HSF4 expression was higher in primary HCC tissues derived from recurrent patients, and positively correlated with invasiveness potentials of cell lines. Clinically, patients with high HSF4 expression had significant poorer prognosis. In vitro experiments showed HSF4 silencing inhibited HCC cell proliferation, migration and invasion, whereas HSF4 overexpression had inverse effects. Moreover, silence of HSF4 induced an epithelial-like phenotype, whereas the overexpression of HSF4 resulted in a mesenchymal-like phenotype in HCC by activating AKT pathway. Further experiments showed that HSF4 could activate AKT pathway in a hypoxia-inducible factor-1α (HIF-1α) dependent, but transforming growth factor-ß (TGF-ß) independent manner. CONCLUSIONS: HSF4 is upregulated in HCC, resulting in greater proliferation, migration and invasion capacities. Moreover, high HSF4 expression is a promising predictive indicator of poor outcome after radical resection. HSF4 may promote aggressive tumour behaviour by enhancing EMT through activating AKT pathway in a HIF1α-dependent manner.

Exosomal miR-9-3p suppresses HBGF-5 expression and is a functional biomarker in hepatocellular carcinoma.

BACKGROUND: Hepatocellular carcinoma (HCC) is the fifth most common cancer and the third leading cause of cancer-related death worldwide. Exosomes are secreted membrane vesicles that play important roles in various diseases by transporting proteins and RNAs, including microRNAs, between cells. However, the function of exosomal miRNA in HCC has not been fully investigated. METHODS: Exosomes were obtained from the sera by ultracentrifugation and were processed for transmission electron microscopy (TEM). Real time PCR were revealed changes of miRNA between patients and normal donors. Predicted targets of miRNA were described by bioinformatics analysis, luciferase reporter assay was used to confirmed whether miR-9-3p regulates target expression. And then miRNA were over-expressed in HCC cell line to study its function, western blotting were used to test expression of miRNA targets, Cell viability and proliferation were analyzed after over-expressed miR-9-3p using MTT and BrdU assay. RESULTS: Serum exosomes from patients with HCC contained significantly lower levels of the miR-9-3p than did serum exosomes from normal donors, suggesting a potential role for this microRNA in HCC. Bioinformatics analysis identified fibroblast growth factor 5 (HBGF-5), which plays an important role in cell proliferation, as a potential miR-9-3p target mRNA. Luciferase reporter assay confirming that miR-9-3p can directly regulate HBGF-5 expression. Consistent with this finding, overexpression of miR-9-3p in three HCC cell lines significantly downregulated HBGF-5 expression at both the mRNA and protein levels. Finally, overexpression of miR-9-3p reduced HCC cell viability and proliferation, and additionally reduced ERK1/2 expression, suggesting a potential mechanism by which miR-9-3p acts. CONCLUSIONS: These results provide new insight into the functions of miR-9-3p and HBGF-5 in HCC and identify miR-9-3p as a potential therapeutic target for HCC.

Hepatogenic differentiation from human adipose-derived stem cells and application for mouse acute liver injury.

Adipose-derived stem cells (ADSCs) derived from adipose tissue have the capacity to differentiate into endodermal, mesoderm, and ectodermal cell lineages in vitro, which are an ideal engraft in tissue-engineered repair. In this study, human ADSCs were isolated from subcutaneous fat. The markers of ADSCs, CD13, CD71, CD73, CD90, CD105, CD166, CYP3A4, and ALB were detected by immunofluorescence assays. Human ADSCs were cultured in a specific hepatogenesis differentiation medium containing HGF, bFGF, nicotinamide, ITS, and oncostatin M for hepatogenic differentiation. The hepatocyte markers were analyzed using immunofluorescence and real-time PCR after dramatic changes in morphology. Hepatocytes derived from ADSCs or ADSCs were transplanted into the mice of liver injury for observation cells colonization and therapy in liver tissue. The result demonstrated that human ADSCs were positive for the CD13, CD71, CD73, CD90, CD105, and CD166 but negative for hepatocyte markers, ALB and CYP3A4. After hepatogenic differentiation, the hepatocytes were positive for liver special markers, gene expression level showed a time-lapse increase with induction time. Human ADSCs or ADSCs-derived hepatocyte injected into the vein could improve liver function repair and functionally rescue the CCl4-treated mice with liver injury, but the ADSCs transplantation was better than ADSCs-derived hepatocyte transplantation. In conclusion, our research shows that a population of hepatocyte can be specifically generated from human ADSCs and that cells may allow for participation in tissue-repair.