title: Retinoic acid induced growth arrest of human breast carcinoma cells requires protein kinase C alpha expression and activity.
abstract: Retinoic acid inhibits proliferation of hormone-dependent, but not hormone-independent breast cancer cells. Retinoic acid-induced changes in cellular proliferation and differentiation are associated with disturbances in growth factor signaling and frequently with changes in protein kinase C expression. PKC delta, epsilon, and zeta are expressed in both hormone-dependent (T-47D) and hormone-independent (MDA-MB-231) cell lines. Retinoic acid arrested T-47D proliferation, induced PKC alpha expression and concomitantly repressed PKC zeta expression. The changes in PKC alpha and PKC zeta reflect retinoic acid-induced changes in mRNA. In contrast, retinoic acid had no effect on growth, or PKC expression in MDA-MB-231 cells. Growth arrest and the induction of PKC alpha, but not the reduction in PKC zeta, resulted from selective activation of RAR alpha. In total, these results support an important role for PKC alpha in mediating the anti-proliferative action of retinoids on human breast carcinoma cells.
authors.affiliation: Institute of Human Nutrition, Columbia University, New York, New York 10032, USA.
authors.forename: Y
authors.initials: Y
authors.lastname: Cho
authors.forename: A P
authors.initials: AP
authors.lastname: Tighe
authors.forename: D A
authors.initials: DA
authors.lastname: Talmage
mesh_terms: D001565:Benzoates / Q000494:pharmacology; D015152:Blotting, Northern; D015153:Blotting, Western; D001943:Breast Neoplasms / Q000201:enzymology / Q000235:genetics / Q000473:pathology*; D002455:Cell Division / Q000187:drug effects*; D004305:Dose-Response Relationship, Drug; D015971:Gene Expression Regulation, Enzymologic; D006801:Humans; D007527:Isoenzymes / Q000235:genetics* / Q000378:metabolism; D009376:Neoplasms, Hormone-Dependent / Q000201:enzymology / Q000235:genetics / Q000473:pathology*; D011493:Protein Kinase C / Q000235:genetics* / Q000378:metabolism; D051571:Protein Kinase C-alpha; D051745:Protein Kinase C-delta; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D018168:Receptors, Retinoic Acid / Q000378:metabolism; D000072482:Retinoic Acid Receptor alpha; D012176:Retinoids / Q000494:pharmacology; D013764:Tetrahydronaphthalenes / Q000494:pharmacology; D014212:Tretinoin / Q000494:pharmacology*; D014407:Tumor Cells, Cultured; D000099221:Protein Kinase C zeta
chemical_list: D001565:Benzoates; D007527:Isoenzymes; D011493:Protein Kinase C; D051571:Protein Kinase C-alpha; D051745:Protein Kinase C-delta; D012333:RNA, Messenger; D018168:Receptors, Retinoic Acid; D000072482:Retinoic Acid Receptor alpha; D012176:Retinoids; D013764:Tetrahydronaphthalenes; D014212:Tretinoin; D000099221:Protein Kinase C zeta; C000607071:RARA protein, human; C068073:Am 580; C496628:PRKCA protein, human; C497258:PRKCD protein, human