Downregulation of 5-hydroxytryptamine receptor 3A expression exerts an anticancer activity against cell growth in colorectal carcinoma cells in vitro.

5-hydroxytryptamine receptor 3A (HTR3A) is an important member of the 5-HT family, which has been suggested to contribute to human tumor development. However, the functions of HTR3A in human cancer, particularly in colorectal carcinoma (CRC) have not been well-characterized. Reverse transcription quantitative polymerase was performed to detect endogenous HTR3A expression in 6 CRC cell lines. HTR3A was then knocked down via a lentivirus-mediated shRNA system to detect the effect of HTR3A silencing on cell proliferation and apoptosis by MTT, colony formation, flow cytometry and western blotting assays in CRC. HTR3A was expressed at different levels in the 6 CRC cell lines. In addition, HTR3A knockdown inhibited CRC cell proliferation and colony formation, resulting in cell cycle arrest and the promotion of cell apoptosis. Additionally, the expression levels of apoptosis-associated proteins including BAD and BAX were increased, while Bcl-2 expression was decreased following HTR3A knockdown. In summary, the data of the present study indicated that HTR3A serves an important role in colon carcinogenesis, but in-depth studies of the mechanisms underlying these data are required to demonstrate whether it may be used as a novel target for CRC therapy.