The HSP90AB1-mediated upregulation of IDO1 can promote the progression of colorectal cancer

Abstract

Colorectal cancer (CRC) is a global challenge, and heat shock protein 90 (HSP90) is identified as a key driver in cancer progression. However, the tumor-promoting mechanism of HSP90 in CRC, particularly HSP90AB1, remains unclear. This study aims to explore and analyze the oncogenic mechanism of HSP90AB1 in CRC and identify potential therapeutic targets. HSP90AB1 expression underwent analysis in CRC cell lines and tissues at mRNA and protein levels. Through the use of shRNA, targeted suppression of HSP90AB1 was achieved in CRC cell lines, enabling analysis of its influence on cell proliferation, invasion, apoptosis, and cell cycle progression. Subsequent investigation focused on elucidating the regulatory relationship between HSP90AB1 and IDO1, employing a combination of bioinformatics approaches and in vitro/vivo experiments. These efforts confirmed IDO1 as a downstream target of HSP90AB1 and provided insight into its role in driving CRC progression. HSP90AB1 exhibits overexpression in both CRC cell lines and tumor tissues (p<0.05). Its downregulation impedes cell proliferation and invasion (p<0.01), promotes apoptosis and cell cycle arrest (p<0.05). Investigation reveals that decreased HSP90AB1 leads to the inhibition of IDO1 (p<0.01), suggesting that IDO1 regulation plays a crucial role in mediating the pro-tumorigenic effects of HSP90AB1. In vivo experiments confirm the substantial reduction in tumor growth upon HSP90AB1 knockdown in xenograft models (p<0.01). However, this tumor-suppressive effect is reversed upon IDO1 overexpression (p<0.01), highlighting IDO1 as a downstream target of HSP90AB1 in CRC progression. HSP90AB1 exerts a regulatory role in the progression of CRC by upregulating IDO1.