title: Inhibition of stearoyl-CoA desaturase activity by the cis-9,trans-11 isomer and the trans-10,cis-12 isomer of conjugated linoleic acid in MDA-MB-231 and MCF-7 human breast cancer cells.
abstract: Conjugated linoleic acid (CLA) is a collective term for a group of positional and geometric conjugated dienoic isomers of linoleic acid. CLA has been shown to have strong inhibitory effects on mammary carcinogenesis both in vitro and in vivo. In this study, we investigated the regulation of human stearoyl-CoA desaturase (SCD, EC 1.14.99.5) expression by CLA in human breast cancer cell lines, MDA-MB-231 and MCF-7. Treatment of the cells with the cis-9,trans-11 and trans-10,cis-12 CLA isomers (45 microM) did not repress SCD mRNA in both MDA-MB-231 and MCF-7 cells. However, the cis-9,trans-11 and trans-10,cis-12 CLA isomers significantly decreased SCD protein levels and SCD activity in MDA-MB-231 cells. In MCF-7 cells, both isomers did not affect protein levels, but they inhibited SCD activity. These results suggest that in MDA-MB-231 cells the cis-9,trans-11 and trans-10,cis-12 CLA isomers regulate human SCD by reducing SCD protein levels, while in MCF-7 cells both isomers have a direct inhibitory effect on SCD enzyme activity.
authors.affiliation: Department of Biochemistry, University of Wisconsin-Madison, 53706, USA.
authors.forename: Youngjin
authors.initials: Y
authors.lastname: Choi
authors.forename: Yeonhwa
authors.initials: Y
authors.lastname: Park
authors.forename: Jayne M
authors.initials: JM
authors.lastname: Storkson
authors.forename: Michael W
authors.initials: MW
authors.lastname: Pariza
authors.forename: James M
authors.initials: JM
authors.lastname: Ntambi
mesh_terms: D016588:Anticarcinogenic Agents / Q000737:chemistry / Q000494:pharmacology*; D015152:Blotting, Northern; D015153:Blotting, Western; D001943:Breast Neoplasms / Q000201:enzymology*; D005227:Fatty Acids / Q000378:metabolism; D006801:Humans; D008041:Linoleic Acids / Q000737:chemistry / Q000494:pharmacology*; D044243:Linoleic Acids, Conjugated; D050356:Lipid Metabolism; D008861:Microsomes / Q000378:metabolism; D012313:RNA / Q000378:metabolism; D012333:RNA, Messenger / Q000378:metabolism; D013230:Stearoyl-CoA Desaturase / Q000187:drug effects* / Q000235:genetics / Q000378:metabolism*; D013237:Stereoisomerism; D014407:Tumor Cells, Cultured
chemical_list: C094849:10,12-octadecadienoic acid; D016588:Anticarcinogenic Agents; D005227:Fatty Acids; D008041:Linoleic Acids; D044243:Linoleic Acids, Conjugated; D012333:RNA, Messenger; C046938:9,11-linoleic acid; D012313:RNA; D013230:Stearoyl-CoA Desaturase