This study was aimed to uncover the effects of miR-124-3p on bladder cancer (BC) by regulating DNA methyltransferase 3B. The expressions of miR-124-3p and DNMT3B mRNA in BC tissues and cell lines were detected using RT-PCR. The expression of DNMT3B in cells was determined using Western blot and immunohistochemistry in tissues. In addition， chromogenic in situ hybridization staining was used to measure the expression of miR-124-3p in tissues. BC cells were transfected with miR-124-3p mimics， miR-124-3p inhibitors， DNMT3B siRNAs， and DNMT3B cDNAs + miR-124-3p mimics. Subsequently， cell proliferation， apoptosis， migration， and invasion were measured using CCK-8， the cytometry test， wound he... More
This study was aimed to uncover the effects of miR-124-3p on bladder cancer (BC) by regulating DNA methyltransferase 3B. The expressions of miR-124-3p and DNMT3B mRNA in BC tissues and cell lines were detected using RT-PCR. The expression of DNMT3B in cells was determined using Western blot and immunohistochemistry in tissues. In addition， chromogenic in situ hybridization staining was used to measure the expression of miR-124-3p in tissues. BC cells were transfected with miR-124-3p mimics， miR-124-3p inhibitors， DNMT3B siRNAs， and DNMT3B cDNAs + miR-124-3p mimics. Subsequently， cell proliferation， apoptosis， migration， and invasion were measured using CCK-8， the cytometry test， wound healing assay， and Transwell assay， respectively. Finally， the relationship between miR-124-3p and DNMT3B was confirmed using dual luciferase reporter gene assay. MiR-124-3p expression was significantly lower and the level of DNMT3B was significantly higher in BC tissues and cell lines compared with the normal controls. MiR-124-3p was verified to target DNMT3B. The transfection of miR-124-3p mimics and DNMT3B siRNAs down-regulated BC cell proliferation， migration， and invasion， as well as induced cell apoptosis; miR-124-3p inhibitors promoted BC cell proliferation， migration， invasion， and reduced cell apoptosis; and the effects of DNMT3B cDNAs can be compromised by miR-124-3p mimics. Thus， we concluded that miR-124-3p could suppress the proliferation， migration， invasion， and promote apoptosis of BC cells by targeting DNMT3B.
