We then analyzed the correlation between POSTN and PTK7 in other types of tumors, including Bladder Urothelial Carcinoma (BLCA), Cholangiocarcinoma (CHOL), Kidney Chromophobe (KICH), Pancreatic adenocarcinoma (PAAD), and the results showed that POSTN was most highly correlated with PTK7 in the tumors (Supplementary Figure 3D–3F). Here, PTK7 is linked to cholangiocarcinoma.