COL1A2 and intrahepatic cholangiocarcinoma: Furthermore, ligand-receptor pair analysis found that fibroblasts preferentially sent signals to cholangiocytes, endothelial cells, and malignant cells by COL1A2-(ITGA2 + ITDB1) (L-R) in tumor samples, which influenced the tumor microbiome through intercellular information exchange and then mediated the immunosuppression and progression of ICC.