COL4A2 and esophageal squamous cell carcinoma: In the current study, potential targeted genes for anti-angiogenesis in both upper and lower ESCC treatment were preliminarily screened out, including ITGB1, Col4A1, Col4A2, ITGA6, LAMA4, LAMB1, and LAMC1, VWF, ITGA5, THBS1, PDGFB, PGF, RHOC, and CTNNB1 (involved in signaling transduction) and UPP1, MGST3, MGST2, AK1, PNP, DAD1, HYAL2, MGLL, COX7A1, and PGM2L1 (involved in cell metabolism).