title: Resveratrol inhibits cancer cell metabolism by down regulating pyruvate kinase M2 via inhibition of mammalian target of rapamycin.
abstract: Metabolism of cancer cells with pyruvate kinase M2 (PKM2) at its centre stage has assumed a prime significance in cancer research in recent times. Cancer cell metabolism, characterized by enhanced glucose uptake, production of lactate and anabolism is considered an ideal target for therapeutic interventions. Expression of PKM2 switches metabolism in favor of cancer cells, therefore, the present study was designed to investigate the hitherto unknown effect of resveratrol, a phytoalexin, on PKM2 expression and resultant implications on cancer metabolism. We observed that resveratrol down-regulated PKM2 expression by inhibiting mTOR signaling and suppressed cancer metabolism, adjudged by decreased glucose uptake, lactate production (aerobic glycolysis) and reduced anabolism (macromolecule synthesis) in various cancer cell lines. A contingent decrease in intracellular levels of ribose-5-phosphate (R5P), a critical intermediate of pentose phosphate pathway, accounted for a reduced anabolism. Consequently, the state of suppressed cancer metabolism resulted in decreased cellular proliferation. Interestingly, shRNA-mediated silencing of PKM2 inhibited glucose uptake and lactate production, providing evidence for the critical role of PKM2 and its mediation in the observed effects of resveratrol on cancer metabolism. Further, an over-expression of PKM2 abolished the observed effects of resveratrol, signifying the role of PKM2 downregulation as a critical function of resveratrol. The study reports a novel PKM2-mediated effect of resveratrol on cancer metabolism and provides a new dimension to its therapeutic potential.
authors.affiliation: National Centre of Applied Human Genetics, School of Life Sciences, Jawaharlal Nehru University, New Delhi, India.
authors.forename: Mohd Askandar
authors.initials: MA
authors.lastname: Iqbal
authors.forename: Rameshwar N K
authors.initials: RN
authors.lastname: Bamezai
mesh_terms: D000332:Aerobiosis / Q000187:drug effects; D000970:Antineoplastic Agents / Q000494:pharmacology*; D001692:Biological Transport / Q000187:drug effects; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D015536:Down-Regulation / Q000187:drug effects*; D020868:Gene Silencing; D005947:Glucose / Q000378:metabolism; D006019:Glycolysis / Q000187:drug effects; D006801:Humans; D019344:Lactic Acid / Q000096:biosynthesis; D011770:Pyruvate Kinase / Q000172:deficiency / Q000235:genetics* / Q000378:metabolism*; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D000077185:Resveratrol; D013267:Stilbenes / Q000494:pharmacology*; D058570:TOR Serine-Threonine Kinases / Q000037:antagonists & inhibitors*
chemical_list: D000970:Antineoplastic Agents; D012333:RNA, Messenger; D013267:Stilbenes; D019344:Lactic Acid; D011770:Pyruvate Kinase; D058570:TOR Serine-Threonine Kinases; D005947:Glucose; D000077185:Resveratrol