MGMT and malignant colon neoplasm: Genes specific to colon cancer and altered only in the proximal colon include DNA repair enzymes Mgmt (O-6-Methylguanine-DNA Methyltransferase) and Parp1 (Poly(ADP-Ribose) Polymerase 1), Mtor, a mediator of response to cellular stress including DNA damage – all were downregulated by one or more HFDs.