CD274 and bile duct cancer: Correlation analysis of TCGA pan-cancer cohorts revealed that the relationship between the ROS-related signature and the CD274 mRNA expression exhibited heterogeneous patterns (Fig. S6C), in which the ROS-related signature did not correlate significantly with the CD274 mRNA expression in liver cancer (LIHC), breast cancer (BRCA), esophageal cancer (ESCA), stomach cancer (STAD), prostate cancer (PRAD), endometrioid cancer (UCEC), MESO, rectal cancer (READ), PAAD, ocular melanoma (UVM), uterine carcinosarcoma (UCS), kidney chromophobe (KICH), ACC, and bile duct cancer (CHOL) cohorts (Fig. S6C).