title: Carnosic acid inhibits proliferation and augments differentiation of human leukemic cells induced by 1,25-dihydroxyvitamin D3 and retinoic acid.
abstract: Carnosic acid, the polyphenolic diterpene derived from rosemary, is a strong dietary antioxidant that exhibits antimutagenic properties in bacteria and anticarcinogenic activity in various cell and animal models. In the present study, we show that carnosic acid (2.5-10 microM) inhibits proliferation of HL-60 and U937 human myeloid leukemia cells (half-maximal inhibitory concentration = 6-7 microM) without induction of apoptotic or necrotic cell death. Growth arrest occurred concomitantly with a transient cell cycle block in the G1 phase, which was accompanied by an increase in the immunodetectable levels of the universal cyclin-dependent kinase inhibitors p21WAFI and p27Kipl. Carnosic acid caused only a marginal induction of differentiation, as monitored by the capacity to generate superoxide radicals and the expression of cell surface antigens (CD11b and CD14) and receptors for the chemotactic peptide N-formyl-L-methionyl-L-leucyl-L-phenylalanine. However, at low concentrations, this polyphenol substantially augmented (100- to 1,000-fold) the differentiating effects of 1,25-dihydroxyvitamin D3 and all-trans retinoic acid. Furthermore, such combinations of carnosic acid and any of these differentiation inducers synergistically inhibited proliferation and cell cycle progression. These results indicate that carnosic acid is capable of antiproliferative action in leukemic cells and can cooperate with other natural anticancer compounds in growth-inhibitory and differentiating effects.
authors.affiliation: Department of Clinical Biochemistry, Faculty of Health Sciences, Ben-Gurion University of the Negev and Soroka Medical Center of Kupat Holim, Beer-Sheva 84 105, Israel. misha@bgumail.bgu.ac.il
authors.forename: M
authors.initials: M
authors.lastname: Steiner
authors.forename: I
authors.initials: I
authors.lastname: Priel
authors.forename: J
authors.initials: J
authors.lastname: Giat
authors.forename: J
authors.initials: J
authors.lastname: Levy
authors.forename: Y
authors.initials: Y
authors.lastname: Sharoni
authors.forename: M
authors.initials: M
authors.lastname: Danilenko
mesh_terms: D045784:Abietanes; D000972:Antineoplastic Agents, Phytogenic; D017209:Apoptosis / Q000187:drug effects; D002117:Calcitriol / Q000494:pharmacology*; D002453:Cell Cycle / Q000187:drug effects; D018797:Cell Cycle Proteins / Q000378:metabolism; D002454:Cell Differentiation / Q000187:drug effects*; D002455:Cell Division / Q000187:drug effects*; D050759:Cyclin-Dependent Kinase Inhibitor p21; D050760:Cyclin-Dependent Kinase Inhibitor p27; D016213:Cyclins / Q000378:metabolism; D004224:Diterpenes / Q000494:pharmacology*; D004347:Drug Interactions; D005434:Flow Cytometry; D016193:G1 Phase / Q000187:drug effects; D018922:HL-60 Cells / Q000473:pathology; D006801:Humans; D007938:Leukemia / Q000473:pathology*; D007951:Leukemia, Myeloid / Q000473:pathology; D010936:Plant Extracts / Q000494:pharmacology*; D027542:Rosmarinus / Q000737:chemistry; D014212:Tretinoin / Q000494:pharmacology*; D014407:Tumor Cells, Cultured; D025521:Tumor Suppressor Proteins / Q000378:metabolism; D020298:U937 Cells / Q000473:pathology
chemical_list: D045784:Abietanes; D000972:Antineoplastic Agents, Phytogenic; C493956:CDKN1A protein, human; D018797:Cell Cycle Proteins; D050759:Cyclin-Dependent Kinase Inhibitor p21; D016213:Cyclins; D004224:Diterpenes; D010936:Plant Extracts; D025521:Tumor Suppressor Proteins; D050760:Cyclin-Dependent Kinase Inhibitor p27; D014212:Tretinoin; D002117:Calcitriol; C018381:salvin