title: Combined Treatment of MCF-7 Cells with AICAR and Methotrexate, Arrests Cell Cycle and Reverses Warburg Metabolism through AMP-Activated Protein Kinase (AMPK) and FOXO1.
abstract: Cancer cells are characterized by metabolic alterations, namely, depressed mitochondrial oxidation, enhanced glycolysis and pentose phosphate shunt flux to support rapid cell growth, which is called the Warburg effect. In our study we assessed the metabolic consequences of a joint treatment of MCF-7 breast cancer cells with AICAR, an inducer of AMP-activated kinase (AMPK) jointly with methotrexate (MTX), a folate-analog antimetabolite that blunts de novo nucleotide synthesis. MCF7 cells, a model of breast cancer cells, were resistant to the individual application of AICAR or MTX, however combined treatment of AICAR and MTX reduced cell proliferation. Prolonged joint application of AICAR and MTX induced AMPK and consequently enhanced mitochondrial oxidation and reduced the rate of glycolysis. These metabolic changes suggest an anti-Warburg rearrangement of metabolism that led to the block of the G1/S and the G2/M transition slowing down cell cycle. The slowdown of cell proliferation was abolished when mitotropic transcription factors, PGC-1α, PGC-1β or FOXO1 were silenced. In human breast cancers higher expression of AMPKα and FOXO1 extended survival. AICAR and MTX exerts similar additive antiproliferative effect on other breast cancer cell lines, such as SKBR and 4T1 cells, too. Our data not only underline the importance of Warburg metabolism in breast cancer cells but nominate the AICAR+MTX combination as a potential cytostatic regime blunting Warburg metabolism. Furthermore, we suggest the targeting of AMPK and FOXO1 to combat breast cancer.
authors.affiliation: Department of Medical Chemistry, Faculty of Medicine, University of Debrecen, Debrecen, H-4032, Hungary.
authors.forename: Tamás
authors.initials: T
authors.lastname: Fodor
authors.affiliation: Department of Medical Chemistry, Faculty of Medicine, University of Debrecen, Debrecen, H-4032, Hungary.|MTA-DE Cell Biology and Signaling Research Group, Debrecen, H-4032, Hungary.
authors.forename: Magdolna
authors.initials: M
authors.lastname: Szántó
authors.affiliation: Department of Medical Chemistry, Faculty of Medicine, University of Debrecen, Debrecen, H-4032, Hungary.|MTA-DE Cell Biology and Signaling Research Group, Debrecen, H-4032, Hungary.
authors.forename: Omar
authors.initials: O
authors.lastname: Abdul-Rahman
authors.affiliation: Department of Medical Chemistry, Faculty of Medicine, University of Debrecen, Debrecen, H-4032, Hungary.|MTA-DE Cell Biology and Signaling Research Group, Debrecen, H-4032, Hungary.
authors.forename: Lilla
authors.initials: L
authors.lastname: Nagy
authors.affiliation: Department of Oncology, Section of Radiation Therapy, Faculty of Medicine, University of Debrecen, Debrecen, H-4032, Hungary.
authors.forename: Ádám
authors.initials: Á
authors.lastname: Dér
authors.affiliation: Department of Dermatology, Faculty of Medicine, University of Debrecen, Debrecen, H-4032, Hungary.
authors.forename: Borbála
authors.initials: B
authors.lastname: Kiss
authors.affiliation: Department of Medical Chemistry, Faculty of Medicine, University of Debrecen, Debrecen, H-4032, Hungary.|MTA-DE Lendület Laboratory of Cellular Metabolism, Debrecen, H-4032, Hungary.|Research Center for Molecular Medicine, University of Debrecen, Debrecen, H-4032, Hungary.
authors.forename: Peter
authors.initials: P
authors.lastname: Bai
mesh_terms: D055372:AMP-Activated Protein Kinases / Q000378:metabolism*; D000620:Aminoimidazole Carboxamide / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000494:pharmacology; D000964:Antimetabolites, Antineoplastic / Q000494:pharmacology; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000494:pharmacology*; D001859:Bone Neoplasms / Q000473:pathology; D001943:Breast Neoplasms / Q000235:genetics / Q000378:metabolism / Q000401:mortality / Q000473:pathology*; D002453:Cell Cycle / Q000187:drug effects; D002455:Cell Division / Q000187:drug effects; D045744:Cell Line, Tumor; D054697:Cytostatic Agents / Q000008:administration & dosage / Q000494:pharmacology*; D004354:Drug Screening Assays, Antitumor; D004357:Drug Synergism; D004734:Energy Metabolism / Q000187:drug effects*; D004790:Enzyme Induction / Q000187:drug effects; D005260:Female; D000071161:Forkhead Box Protein O1; D051858:Forkhead Transcription Factors / Q000378:metabolism*; D015972:Gene Expression Regulation, Neoplastic; D006019:Glycolysis / Q000187:drug effects; D006801:Humans; D007773:Lactates / Q000378:metabolism; D061986:MCF-7 Cells; D053078:Membrane Potential, Mitochondrial / Q000187:drug effects; D008727:Methotrexate / Q000008:administration & dosage / Q000494:pharmacology*; D058990:Molecular Targeted Therapy; D009363:Neoplasm Proteins / Q000378:metabolism*; D012516:Osteosarcoma / Q000473:pathology; D034622:RNA Interference; D012265:Ribonucleotides / Q000008:administration & dosage / Q000494:pharmacology*; D014157:Transcription Factors / Q000037:antagonists & inhibitors
chemical_list: D000964:Antimetabolites, Antineoplastic; D054697:Cytostatic Agents; C085126:FOXO1 protein, human; D000071161:Forkhead Box Protein O1; D051858:Forkhead Transcription Factors; D007773:Lactates; D009363:Neoplasm Proteins; D012265:Ribonucleotides; D014157:Transcription Factors; D000620:Aminoimidazole Carboxamide; D055372:AMP-Activated Protein Kinases; C031143:AICA ribonucleotide; D008727:Methotrexate