miR-144-3p inhibits cell proliferation of colorectal cancer cells by targeting BCL6 via inhibition of Wnt/β-catenin signaling

Background It has been shown that miR-144-3p regulates cell proliferation, apoptosis, migration and invasion in various cancers. However, the function and expression of miR-144-3p in colorectal cancer (CRC) remained obscure. Methods Immunohistochemical (IHC) staining was performed to investigate the protein expression of BCL6 in CRC tissues. The effect of BCL6 and miR-144-3p on CRC cells was explored through methylthiazolyl tetrazolium (MTT) assay, colony formation and cell cycle assays. Luciferase reporter assays, reverse transcription quantitative polymerase chain reaction (RT-qPCR) and Western blot assay were carried out to determine that BCL6 is directly regulated by miR-144-3p. Results Our results showed that miR-144-3p is down-regulated in CRC and correlates with the tumor progression of CRC patients. miR-144-3p inhibits cell proliferation and delays G1/S phase transition of CRC cells. Moreover, we found that BCL6 is a new target of miR-144-3p. Furthermore, BCL6 is a mediator of miR-144-3p repression of cell proliferation and cell cycle arrest in CRC cells. miR-144-3p repression of Wnt/beta-catenin signaling is mediated by BCL6 in CRC cells. Conclusions Overall, the effect of the miR-144-3p/BCL6 axis on regulating CRC carcinogenesis was demonstrated, and miR-144-3p was identified as a potential prognostic and therapeutic target in colorectal cancer.