Analysis of TCGA colorectal cancer data revealed that GLS1 expression is significantly correlated with a HIF metagene signature, which is based on the combined expression of 10 HIF-1 target genes implicated in breast cancer metastasis (VEGFA, PDGFB, LOX, CXCR3, ANGPTL4, L1CAM, SLC2A1, P4HA1, P4HA2, and MET). This evidence concerns the gene P4HA1 and breast cancer.