Deubiquitinating enzyme JOSD2 modulates cGAS to facilitate immune evasion in colorectal cancer.

Colorectal cancer (CRC) remains a formidable clinical challenge, many patients exhibit limited responses to conventional chemotherapy and targeted therapies. Although immunotherapy has demonstrated potential, its efficacy is largely restricted to a subset of patients with high microsatellite instability (MSI-H), highlighting the critical need to identify key molecular drivers of immune evasion in CRC. Through comprehensive bioinformatic analysis, we identified the deubiquitinating enzyme JOSD2 as a key player in CRC progression, with elevated expression correlating with poor prognosis in MSI-H patients (HR = 4.79, 95% CI: 3.6-7.96) and dysregulation of multiple immune-related pathways. Mechanistically, we discovered that JOSD2 suppresses cGAS enzymatic activity by removing K27-linked ubiquitination, thereby promoting M2 polarization of macrophages, a process critical for immunosuppression in the tumor microenvironment. Furthermore, using the JOSD2 catalytic inhibitor HY041004, we demonstrated both in vitro and in vivo that the inhibition of JOSD2 activated the cGAS-STING signaling pathway, leading to robust anti-tumor effects in CRC. These findings not only uncover a novel immunomodulatory mechanism in colorectal cancer but also provide a therapeutic rationale for the development of JOSD2-targeted anticancer strategies.