There is an upregulation of folate-dependent 1C metabolic enzymes, including folate receptor-1 (FOLR1), dihydrofolate reductase (DHFR), and serine hydroxymethyltransferase 1 (SHMT1) in CRC cells, unlike in non-transformed cells (162, 163). The gene discussed is DHFR; the disease is colorectal carcinoma.