PDGFB and colorectal carcinoma: To test the above hypothesis, several angiogenesis-related cytokines were analyzed for their mRNA levels in CRC cells with sh-USP13 or Flag-USP13 expression (Fig. 4A,B) and the mRNA levels of VEGFA, VEGFB, VEGFC, VEGFD, PDGFB, PDGFC, THBS1, WNT7B, PGF, bFGF, MMP2, and CXCL9 were quantified.