Comprehensive analysis on expression and biological role of miR-224 in hepatocellular carcinoma / 中国肿瘤生物治疗杂志

ABSTRACT

@#[Abstract] Objective: To analyze the expression level of miR-224 in cancer tissues and plasma of hepatocellular carcinoma (HCC) patients, and its correlation with clinicopathological characteristics, diagnosis and prognosis of HCC patients, and to further analyze its mechanism of action in the occurrence and development of liver cancer through bioinformatics analysis and in vitro experiments. Methods: The expression level of miR-224 in HCC tissues and normal tissues was analyzed using large sample data from Gene Expression Omnibus (GEO). qPCR method was used to verify the expression level of miR-224 in the tumor tissues and corresponding adjacent tissues that surgically resected from 80 HCC patients in Hebei Provincial People ’s Hospital from January 2017 to January 2020; in addition, the miR-224 level was also examined in plasma samples from 30 HCC patients. The Kaplan-Meier plotter database was used to analyze the correlation between the miR-224 expression and the overall survival time of HCC patients. The biological processes and signal pathways involving miR-224 were analyzed using bioinformatics tools. Hepatocellular carcinoma HepG2 cells were transfected with miR-224 inhibitor, and then Clone formation experiment, Transwell chamber experiment, qPCR and WB methods were used to detect the effect of miR-224 knockdown on the proliferation and invasion of HepG2 cells and the expression level of EMT-related molecules. Results: The results of GEO database analysis showed that the expression level of miR-224 in HCC tissues was significantly higher than that in normal tissues. The results of clinical specimen verification showed that the expression level of miR-224 in the tumor tissues and plasma of HCC patients was significantly higher than that in the corresponding adjacent tissues and plasma from healthy controls (all P<0.01). The expression level of miR-224 was significantly correlated with the TNM stage, lymph node metastasis status and tumor size of HCC patients (P<0.05 or P<0.01). ROC analysis indicated that miR-224 showed a prominent diagnostic value in liver cancer, and the increased expression level of miR-224 was significantly related to the poor prognosis of HCC patients (P<0.05). Functional enrichment analysis revealed that miR-224 was mainly involved in the mTOR signaling pathway, AGE-RAGE signaling pathway, Rap1 signaling pathway, Ras signaling pathway, ErbB signaling pathway, HIF-1 signaling pathway and p53 signaling pathway and other signaling pathways related to tumor occurrence and development. Knockdown of miR-224 could significantly inhibit the colony formation and invasion of HepG2 cells and affect the expression of EMT-related markers (P<0.05 or P<0.01). Conclusion: miR-224 is highly expressed in HCC tissues and plasma and is significantly related to the poor prognosis of HCC patients. Knockdown of miR-224 expression can inhibit the colony formation, invasion and EMT process of liver cancer HepG2 cells.