ART1 knockdown decreases the IL-6-induced proliferation of colorectal cancer cells.

Colorectal cancer (CRC) is a worldwide health concern. Chronic inflammation is a risk factor for CRC, and interleukin-6 (IL-6) plays a pivotal role in this process. Arginine-specific mono-ADP-ribosyltransferase-1 (ART1) positively regulates inflammatory cytokines. ART1 knockdown reduces the level of glycoprotein 130 (gp130), a key transducer in the IL-6 signalling pathway. However, the relationship between ART1 and IL-6 and the resulting effects on IL-6-induced proliferation in CRC cells remain unclear. The aims of this study were to investigate the effects of ART1 knockdown on IL-6-induced cell proliferation in vitro and use an in vivo murine model to observe the growth of transplanted tumours. The results showed that compared with the control, ART1-sh cancer cells induced by IL-6 exhibited reduced viability, a lower rate of colony formation, less DNA synthesis, decreased protein levels of gp130, c-Myc, cyclin D1, Bcl-xL, and a reduced p-STAT3/STAT3 ratio (P < 0.05). Moreover, mice transplanted with ART1-sh CT26 cells that had high levels of IL-6 displayed tumours with smaller volumes (P < 0.05). ART1 and gp130 were colocalized in CT26, LoVo and HCT116 cells, and their expression was positively correlated in human CRC tissues. Overall, ART1 may serve as a promising regulatory factor for IL-6 signalling and a potential therapeutic target for human CRC.