miR-93-5p knockdown repressed hepatocellular carcinoma progression via increasing ERBB4 and TETs-dependent DNA demethylation

Background: microRNAs (miRNAs) are involved in hepatocellular carcinoma (HCC) development and can control gene expression via directly targeting or regulating DNA methylation. This research aims to analyse the mechanism of miR-93-5p on HCC progression.

Methods: miR-93-5p, Erb-B2 receptor tyrosine kinase 4 (ERBB4) and ten-eleven translocation methyl-cytosine dioxygenases (TET1, TET2 and TET3) abundances were measured via quantitative reverse transcription polymerase chain reaction and Western blotting. The binding interaction was examined by dual-luciferase reporter analysis and chromatin immunoprecipitation. Cell proliferation and apoptosis were assessed via Cell Counting Kit-8, colony formation and flow cytometry. The DNA methylation of ERBB4 was detected via specific polymerase chain reaction. SNU-449 cells were subcutaneously inoculated into the BALB/c nude mice to establish the in vivo model for HCC, and the in vivo function of miR-93-5p was analysed by intratumoral injections of miR-93-5p antogomir.

Results: miR-93-5p abundance was enhanced and ERBB4 level was reduced in HCC tumour tissues of 62 patients and HCC cell lines, in contrast with that in paired normal tissues of 62 patients and normal cell lines. ERBB4 was targeted by miR-93-5p. miR-93-5p knockdown or ERBB4 overexpression repressed HCC cell proliferation and promoted apoptosis via decreasing cell viability and colony ability and inducing cycle arrest. ERBB4 silence attenuated the influence of miR-93-5p knockdown on cell proliferation and apoptosis. ERBB4 promoter DNA methylation level was enhanced in HCC samples and cell lines, and ERBB4 abundance was increased via TETs (TET1, TET2 and TET3). miR-93-5p targeted TETs to modulate ERBB4 abundance. TETs silence relieved the influence of miR-93-5p knockdown on cell proliferation and apoptosis. miR-93-5p knockdown decreased HCC growth in a xenograft model.

Conclusion: miR-93-5p knockdown repressed the progression of HCC via increasing ERBB4 and TETs-dependent DNA demethylation.