TPMT and xeroderma pigmentosum: Whereas epidermal growth factor receptor (EGFR), FBJ murine osteosarcoma viral oncogene homolog (FOS), nuclear factor of kappa light polypeptide gene enhancer in B-cells 1 (NFKB1), peroxisome proliferator-activated receptor alpha (PPARα), retinoid X receptor alpha (RXRα), retinoid X receptor beta (RXRβ), thiopurine S-methyltransferase (TPMT), UDP-glucose ceramide glucosyltransferase (UGCG), and xeroderma pigmentosum, complementation group C (XPC) genes were significantly downregulated in DLD-1 BAX–BAK DKO cells.