title: Low dose leflunomide activates PI3K/Akt signalling in erythroleukemia cells and reduces apoptosis induced by anticancer agents.
abstract: Rheumatoid arthritis (RA) is characterized by persistent joint synovial tissue inflammation. Leflunomide is an immunomodulatory agent that has been approved for treatment of active RA. In the past few years, uses other than RA treatment have appeared. Leflunomide has been reported to show antitumor potential through inhibition of cancer cell proliferation. We thus tested the antiproliferative potential of leflunomide on HEL and K562 erythroleukemia cells. The findings summarized in this report demonstrate for the first time that low dose leflunomide prolonged survival and reduced apoptosis induced by several anticancer agents in erythroleukemia cells. We showed that in treated cells, leflunomide reduced the signalling pathways involved in promoting apoptosis by reducing p38 MAPK and JNK basal activity. On the other hand, leflunomide transiently activated the ERK signalling pathway and induced a sustained activation of Akt. We also showed that leflunomide reduced caspase-3 activity and DNA fragmentation induced by anticancer agents. By using an inhibitory strategy, we showed that inhibition of Akt activation but not ERK abolished the protective effect of leflunomide. Thus our findings suggested that leflunomide reduced apoptosis induced by anticancer agents through PI3K/Akt signalling activation.
authors.affiliation: Laboratoire de Biochimie, UPRES EA 4021, Faculté de Pharmacie, 2 rue du Docteur Marcland, 87025 Limoges Cedex, France.
authors.forename: D Y
authors.initials: DY
authors.lastname: Leger
authors.forename: B
authors.initials: B
authors.lastname: Liagre
authors.forename: J L
authors.initials: JL
authors.lastname: Beneytout
mesh_terms: D000970:Antineoplastic Agents / Q000627:therapeutic use*; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000494:pharmacology; D017209:Apoptosis / Q000187:drug effects*; D053148:Caspase 3 / Q000378:metabolism; D049109:Cell Proliferation / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D053938:DNA Fragmentation / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D004789:Enzyme Activation / Q000187:drug effects; D005047:Etoposide / Q000031:analogs & derivatives / Q000494:pharmacology; D006801:Humans; D007555:Isoxazoles / Q000494:pharmacology*; D020014:K562 Cells; D000077339:Leflunomide; D004915:Leukemia, Erythroblastic, Acute / Q000188:drug therapy* / Q000378:metabolism; D048670:MAP Kinase Kinase 4 / Q000378:metabolism; D020935:MAP Kinase Signaling System / Q000187:drug effects; D048055:Mitogen-Activated Protein Kinase 8 / Q000378:metabolism; D016328:NF-kappa B / Q000378:metabolism; D009943:Organophosphorus Compounds / Q000494:pharmacology; D019869:Phosphatidylinositol 3-Kinases / Q000378:metabolism*; D051057:Proto-Oncogene Proteins c-akt / Q000378:metabolism*; D015398:Signal Transduction / Q000187:drug effects*; D019311:Staurosporine / Q000494:pharmacology; D048051:p38 Mitogen-Activated Protein Kinases / Q000378:metabolism
chemical_list: D000970:Antineoplastic Agents; D007555:Isoxazoles; D016328:NF-kappa B; D009943:Organophosphorus Compounds; C061400:etoposide phosphate; D005047:Etoposide; D019869:Phosphatidylinositol 3-Kinases; D051057:Proto-Oncogene Proteins c-akt; D048055:Mitogen-Activated Protein Kinase 8; D048051:p38 Mitogen-Activated Protein Kinases; D048670:MAP Kinase Kinase 4; D053148:Caspase 3; D000077339:Leflunomide; D019311:Staurosporine