Methyltransferase-like 3 Aggravates HCC Development via Mediating N6-Methyladenosine of Ubiquitin-Specific Protease 7.

We aimed to investigate the role of methyltransferase-like 3 (METTL3) in regulating HCC by mediating m6A level of ubiquitin-specific protease (USP7). METTL3 levels and m6A contents in HCC tissues and cells were detected. Potential correlations between METTL3 level and lymphatic metastasis, tumor size, tumor staging, and overall survival of HCC patients were analyzed. Moreover, its regulatory effects on proliferative, migratory, and invasive rates of HCC cells were examined. Potential methylation of USP7 in HCC was predicted using an online software, and the correlation between USP7 and METTL3 was assessed. METTL3 and m6A were increased both in HCC cells and tissues. High level of METTL3 was associated with the incidence of lymphatic metastasis, large tumor size, advanced tumor staging, and low overall survival of HCC. Silencing of METTL3 reduced proliferation, migration, and invasion rates. USP7 was predicted to have a methylation site regulated by METTL3. It was upregulated in HCC and associated with METTL3 level positively. USP7 silencing decreased proliferation, migration, and invasion rates of HCC cells. METTL3 promotes HCC to proliferate, migrate, and invade by regulating m6A methylation of USP7.

LncRNA PCGEM1 mediates oxaliplatin resistance in hepatocellular carcinoma via miR-129-5p/ETV1 axis in vitro.

BACKGROUND: Hepatocellular carcinoma (HCC) is one of the most severe malignant cancers that leads to high death rate worldwide. Recent research revealed that long non-coding RNAs (lncRNAs) exert a critical role regarding chemoresistance in numerous cancers, including HCC. OBJECTIVES: Our research aimed to explore the function and molecular mechanism of lncRNA PCGEM1 on oxaliplatin resistance of HCC in vitro. MATERIAL AND METHODS: Expression of the lncRNA PCGEM1, together with miR-129-5p, and the mRNA level of ETV1 and drug resistance-related genes including LRPA, MDR1 and MDR3 were determined using quantitative real-time polymerase chain reaction (qRT-PCR) in an oxaliplatin-resistant HCC cell line (Hep3B/OXA). Cell Counting Kit-8 (CCK-8) was employed to assess the viability and cell survival rate, and transwell assays were performed to measure the number of migrated or invaded cells. In addition, the relation among lncRNA PCGEM1, miR-129-5p and ETV1 were determined using luciferase assay. RESULTS: Our data indicated that PCGEM1 and ETV1 expression were enhanced in Hep3B/OXA cells. Furthermore, knockdown of lncRNA PCGEM1 significantly decreased the migration, invasion and mRNA expressions of LRPA, MDR1 and MDR3, and the cell viability in Hep3B/OXA cells. The starBase online tool and luciferase assays verified that miR-129-5p targeted PCGEM1 and ETV1, signifying that PCGEM1 could enhance ETV1 expression via suppressing miR-129-5p. CONCLUSIONS: Our findings demonstrated that PCGEM1 modulated oxaliplatin resistance by targeting the miR-129-5p/ETV1 pathway in HCC in vitro, suggesting a potential strategy for the treatment of chemoresistant HCC.

Clinicopathological significance of expression of Tspan-1, Jab1 and p27 in human hepatocellular carcinoma.

The aim of this study was to investigate the expression of Tspan-1, Jab1 and p27 in human hepatocellular carcinoma (HCC) and their clinicopathological significance. The expression of Tspan-1, Jab1 and p27 was detected in HCC tissues, the tissues around cancer (76 cases), and the normal tissues around the liver hemangiomas (10 cases). The overexpression of Tspan-1 and Jab1 was found in HCC tissues, positively correlated with clinical stage and negatively correlated with survival rate. The expression of p27 was found inversely linked to which of Tspan-1 and Jab1. In conclusion, the expression of Tspan-1, Jab1 and p27 is significantly associated with development of HCC. Overexpression of Tspan-1 and Jab1 suggests poor prognosis but overexpression of p27 may expect good prognosis for patients with HCC.

Suppression of TSPAN1 by RNA interference inhibits proliferation and invasion of colon cancer cells in vitro.

AIMS AND BACKGROUND: To investigate effect ofTSPAN1 downregulation by RNA interference (RNAi) on proliferation and invasion of human colon cancer cells in vitro. METHODS AND STUDY DESIGN: RNAi was performed using the vector (pU6H1-GFP)-based small-interfering RNA (siRNA) plasmid gene silencing system to specifically knock down TSPAN1 expression in a colon cancer cell line, HCT-8. The expression of TSPAN1 mRNA was detected by reverse-transcription polymerase chain reaction. TSPAN1 protein expression was observed using Western blots and immunofluorescent microscopy. Cell proliferation and cell cycle assay were measured using methyl thiazolyl tetrazolium (MTT) and flow cytometry, respectively. The invasive ability of HCT-8 cells was examined using a duel culture chamber separated by polycarbonate membranes coated with Matrigel (8.0-microm pore size). RESULTS: After transfection with the TSPAN1 siRNA plasmid, TSPAN1 mRNA and protein expression was significantly decreased. The decrease in mRNA and protein was associated with a significant decrease in TSPAN1 fluorescent staining and a decrease in cell proliferation due to cell cycle arrest in the G1/G0 phase. A significant decrease in the number of invading HCT-8 cells was associated with these changes. CONCLUSION: RNAi-mediated downregulation of TSPAN1 expression significantly inhibits the proliferation and invasion of colon cancer cells in vitro. This finding suggests that TSPAN1 plays an important role in colon cancer progression, and RNAi targeting of TSPAN1 may be a potential therapeutic strategy for the treatment of colon cancer.