Dysregulation of MiR-144-5p/RNF187 Axis Contributes To the Progression of Colorectal Cancer

BACKGROUND AND OBJECTIVES: RING finger protein 187 (RNF187) belongs to RING domain-containing E3 ligases family, which was recently reported to be involved in oncogenesis and development of several cancers. This research aims to clarify the role of RNF187 in colorectal cancer (CRC) development. METHODS: The expression of RNF187 and miR-144-4p were determined by quantitative real-time polymerase chain reaction (qRT-PCR). The levels of RNF187 protein were assessed by western blot analysis. Cell Counting Kit-8 (CCK8) assay, clonogenic assay, cell scratch test and transwell assay were used to determine the proliferation, migration and invasion of CRC cells in vitro. The binding of miR-144-5p and RNF197 mRNA was validated by luciferase reporter assays. Tumor-bearing nude mice were used to determine CRC cells growth in vivo. RESULTS: RNF187 expression significantly increased in CRC specimens and cell lines compared to normal colon tissues and normal colonic mucosa cell line, respectively. Upregulation of RNF187 expression was inversely correlated to poor prognosis in CRC patients. In addition, knockdown of RNF187 expression inhibited the proliferation, migration, and invasion but promoted the apoptosis of CRC lines Caco-2 and SW480 cells. Further studies validated that RNF187 was the direct target of miR-144-5p. The expression of miR-144-5p was downregulated in CRC tissues, which was negatively correlated to the expression of RNF187. Restoration of miR-144-5p significantly inhibited the progression of CRC cells and its anti-tumor effects could be abrogated by overexpression of RNF187. CONCLUSION: Our findings demonstrate the deregulation of miR-144-5p/ RNF187 axis in CRC, as well as its role in regulation of the tumor progression, thus providing a novel therapeutic strategy for CRC treatment.