|
1
|
Stepp MW, Doll MA, Samuelson DJ, Sanders MAG, States JC, Hein DW. Congenic rats with higher arylamine N-acetyltransferase 2 activity exhibit greater carcinogen-induced mammary tumor susceptibility independent of carcinogen metabolism. BMC Cancer 2017; 17:233. [PMID: 28359264 PMCID: PMC5374573 DOI: 10.1186/s12885-017-3221-9] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2016] [Accepted: 03/22/2017] [Indexed: 11/19/2022] Open
Abstract
Background Recent investigations suggest role(s) of human arylamine N-acetyltransferase 1 (NAT1) in breast cancer. Rat NAT2 is orthologous to human NAT1 and the gene products are functional homologs. We conducted in vivo studies using F344.WKY-Nat2rapid/slow rats, congenic at rat Nat2 for high (rapid) and low (slow) arylamine N-acetyltransferase activity, to assess a possible role for rat NAT2 in mammary tumor susceptibility. Methods Mammary carcinogens, methylnitrosourea (MNU) and 7,12-dimethylbenzanthracene (DMBA) neither of which is metabolized by N-acetyltransferase, were administered to assess mammary tumors. MNU was administered at 3 or 8 weeks of age. DMBA was administered at 8 weeks of age. NAT2 enzymatic activity and endogenous acetyl-coenzyme A (AcCoA) levels were measured in tissue samples and embryonic fibroblasts isolated from the congenic rats. Results Tumor latency was shorter in rapid NAT2 rats compared to slow NAT2 rats, with statistical significance for MNU administered at 3 and 8 weeks of age (p = 0.009 and 0.050, respectively). Tumor multiplicity and incidence were higher in rapid NAT2 rats compared to slow NAT2 rats administered MNU or DMBA at 8 weeks of age (MNU, p = 0.050 and 0.035; DMBA, p = 0.004 and 0.027, respectively). Recombinant rat rapid-NAT2, as well as tissue samples and embryonic fibroblasts derived from rapid NAT2 rats, catalyzed p-aminobenzoic acid N-acetyl transfer and folate-dependent acetyl-coenzyme A (AcCoA) hydrolysis at higher rates than those derived from rat slow-NAT2. Embryonic fibroblasts isolated from rapid NAT2 rats displayed lower levels of cellular AcCoA than slow NAT2 rats (p < 0.01). Conclusions A novel role for rat NAT2 in mammary cancer was discovered unrelated to carcinogen metabolism, suggesting a role for human NAT1 in breast cancer.
Collapse
Affiliation(s)
- Marcus W Stepp
- Department of Pharmacology and Toxicology, School of Medicine, University of Louisville, Louisville, KY, 40202, USA.,James Graham Brown Cancer Center, University of Louisville, Louisville, KY, 40202, USA
| | - Mark A Doll
- Department of Pharmacology and Toxicology, School of Medicine, University of Louisville, Louisville, KY, 40202, USA.,James Graham Brown Cancer Center, University of Louisville, Louisville, KY, 40202, USA
| | - David J Samuelson
- James Graham Brown Cancer Center, University of Louisville, Louisville, KY, 40202, USA.,Department of Biochemistry & Molecular Genetics, School of Medicine, University of Louisville, Louisville, KY, 40202, USA
| | - Mary Ann G Sanders
- Department of Pathology, University of Louisville Hospital, Louisville, KY, 40202, USA
| | - J Christopher States
- Department of Pharmacology and Toxicology, School of Medicine, University of Louisville, Louisville, KY, 40202, USA.,James Graham Brown Cancer Center, University of Louisville, Louisville, KY, 40202, USA
| | - David W Hein
- Department of Pharmacology and Toxicology, School of Medicine, University of Louisville, Louisville, KY, 40202, USA. .,James Graham Brown Cancer Center, University of Louisville, Louisville, KY, 40202, USA.
| |
Collapse
|