A novel exploration of COL11A1's role in regulating myeloid-derived suppressor cell activation within the colon cancer microenvironment.

This study aimed to elucidate the role of collagen type XI alpha 1 (COL11A1)-positive cancer-associated fibroblasts (CAFs) in modifying the tumor microenvironment of colon cancer (CC) and facilitating immune evasion through interactions with myeloid-derived suppressor cells (MDSCs). Using single-cell transcriptomic sequencing, we analyzed the interplay between COL11A 1-positive CAFs and MDSCs in the CC microenvironment, focusing on how COL11A1 impacts MDSC differentiation and activation. The results demonstrate that COL11A1 expression in fibroblasts significantly enhances matrix metalloproteinase (MMP)3 and MMP13 expression, leading to paracrine induction of MDSC differentiation and activation, which promotes immune evasion and tumor growth. Additionally, we observed that COL11A1 knockout (COL11A1(KO)) suppresses tumor growth and hinders immune evasion. These findings underscore the essential role of COL11A 1-positive CAFs in establishing an immunosuppressive tumor microenvironment conducive to CC progression. By elucidating the molecular pathway through which COL11A1 influences MDSC activity, this research suggests new therapeutic avenues for targeting the tumor microenvironment in CC, particularly through modulating COL11A1 expression in CAFs.