{"database":"biostudies-literature","file_versions":[],"scores":null,"additional":{"omics_type":["Unknown"],"volume":["95(4)"],"submitter":["Engelbergs J"],"pubmed_abstract":["Differential repair of structurally distinct mutagenic lesions in critical genes may influence the cellular risk of malignant conversion. We have investigated rat mammary tumorigenesis induced by N-ethyl-N-nitrosourea (EtNU) versus N-methyl-N-nitrosourea (MeNU) with respect to tumor incidence, ras gene mutation, and gene-specific repair. Both carcinogens induced mammary adenocarcinomas at high yield. In mammary epithelia (very low expression of O6-alkylguanine-DNA alkyltransferase, MGMT), O6-methylguanine (O6-MeGua) was eliminated from transcribed (H-ras and beta-actin) and inactive genes (IgE heavy chain) at the same slow rate as determined for bulk genomic DNA. The persistence of O6-MeGua in DNA correlated with a high frequency of G:C --> A:T transition mutations at codon 12 of the H-ras"],"journal":["Proceedings of the National Academy of Sciences of the United States of America"],"pagination":["1635-40"],"full_dataset_link":["https://www.ebi.ac.uk/biostudies/studies/S-EPMC19127"],"repository":["biostudies-literature"],"pubmed_title":["Fast repair of O6-ethylguanine, but not O6-methylguanine, in transcribed genes prevents mutation of H-ras in rat mammary tumorigenesis induced by ethylnitrosourea in place of methylnitrosourea."],"pmcid":["PMC19127"],"pubmed_authors":["Engelbergs J","Rajewsky MF","Galhoff A","Thomale J"],"additional_accession":[]},"is_claimable":false,"name":"Fast repair of O6-ethylguanine, but not O6-methylguanine, in transcribed genes prevents mutation of H-ras in rat mammary tumorigenesis induced by ethylnitrosourea in place of methylnitrosourea.","description":"Differential repair of structurally distinct mutagenic lesions in critical genes may influence the cellular risk of malignant conversion. We have investigated rat mammary tumorigenesis induced by N-ethyl-N-nitrosourea (EtNU) versus N-methyl-N-nitrosourea (MeNU) with respect to tumor incidence, ras gene mutation, and gene-specific repair. Both carcinogens induced mammary adenocarcinomas at high yield. In mammary epithelia (very low expression of O6-alkylguanine-DNA alkyltransferase, MGMT), O6-methylguanine (O6-MeGua) was eliminated from transcribed (H-ras and beta-actin) and inactive genes (IgE heavy chain) at the same slow rate as determined for bulk genomic DNA. The persistence of O6-MeGua in DNA correlated with a high frequency of G:C --> A:T transition mutations at codon 12 of the H-ras","dates":{"release":"1998-01-01T00:00:00Z","publication":"1998 Feb","modification":"2025-04-04T09:42:11.612Z","creation":"2019-03-27T00:17:46Z"},"accession":"S-EPMC19127","cross_references":{"pubmed":["9465068"],"doi":["10.1073/pnas.95.4.1635"]}}