COL8A1 and pancreatic adenocarcinoma: In PAAD, the top 10 related genes were COL6A3, COL5A2, RAB31, ADAM12, FBN1, COL8A1, NID2, COL3A1, CDH11, and FSTL1. In the other six cancers, COL6A3 and its family collagen members appeared most frequently, all of which were associated with extracellular matrix (ECM) organization in GO analysis (Figure 3A).