Thus, at least for five enzymes SQLE, FDFT1, MVD, CYP51A1 and TM7SF2, the significance of PPIs with their participation in the cancer context was shown, so the revealing of other cancer-specific PPIs through gene co-expression analysis, functional and clinical annotation of common protein partners for target enzymes can help to expand current understanding of cancer interactomics. This evidence concerns the gene CYP51A1 and cancer.