CXCL12 and colorectal cancer: In phase II, we focused on five HIF-coding genes (HIF1A, HIF1B, HIF2A, HIF2B and HIF3A) and two hypoxia-inducible genes (LOX and CXCL12) and investigated the relationship of their SNPs (n = 77) with the risk of outcome in an additional colorectal cancer patient cohort (n = 535).