title: Indomethacin induces apoptosis in 786-O renal cell carcinoma cells by activating mitogen-activated protein kinases and AKT.
abstract: Studies on chemoprevention of cancer are generating increasing interest. The anti-neoplastic effect of nonsteroidal anti-inflammatory drugs (NSAIDs) involves cyclooxygenase (COX)-dependent and COX-independent mechanisms. Evidence suggests that mitogen-activated protein kinases (MAPKs) may mediate apoptotic signaling induced by anti-neoplastic agents. While many reports have revealed the existence of MAPK activation in apoptosis induced by various stimuli, the signaling transduction pathways used by NSAIDs to trigger apoptosis in human renal cell carcinoma (RCC) remain largely unknown. Treatment of RCC 786-O cells with indomethacin resulted in growth regression and apoptosis. Caspase-dependent apoptosis was evidenced by the detection of enzymatic activities of caspase-3, caspase-6, and caspase-9 and suppression of toxicity using a caspase inhibitor. Indomethacin treatment was associated with increased expression of glucose-regulated protein 78 (GRP78) and C/EBP homologus protein (CHOP) and activation of ATF-6, characteristics of endoplasmic reticulum stress. In addition, the concomitant induction of peroxisome proliferator-activated receptor (PPAR), especially PPAR-beta, was apparent in treated cells. Western blotting revealed the activation of extracellular signal-regulated kinase (ERK), p38 MAPK, and c-Jun N-terminal kinase (JNK) with indomethacin treatment. Selective inhibitors of ERK, p38 MAPK, and JNK suppressed the induction of GRP78, CHOP, and PPAR-beta, attenuated indomethacin-induced cytotoxicity and reduced increased caspase activity. LY294002, a phosphoinositide-3 kinase (PI3K)/AKT inhibitor, and Trolox, an antioxidant, suppressed indomethacin-induced cytotoxicity and caspase activation. Furthermore, Trolox attenuated indomethacin-induced increased phosphorylation in ERK, p38 MAPK, JNK, and AKT. In conclusion, our findings establish a mechanistic link between the oxidative stress, PI3K/AKT pathway, MAPK pathway and indomethacin-induced cellular alterations and apoptosis in 786-O cells.
authors.affiliation: Division of Urology, Department of Education and Research, Taichung Veterans General Hospital, and Institute of Medical Technology, National Chung-Hsing University, Taichung, Taiwan.
authors.forename: Yen-Chuan
authors.initials: YC
authors.lastname: Ou
authors.forename: Chi-Rei
authors.initials: CR
authors.lastname: Yang
authors.forename: Chen-Li
authors.initials: CL
authors.lastname: Cheng
authors.forename: Shue-Ling
authors.initials: SL
authors.lastname: Raung
authors.forename: Yu-Yeh
authors.initials: YY
authors.lastname: Hung
authors.forename: Chun-Jung
authors.initials: CJ
authors.lastname: Chen
mesh_terms: D051702:Activating Transcription Factor 6 / Q000378:metabolism; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000494:pharmacology*; D000970:Antineoplastic Agents / Q000494:pharmacology*; D017209:Apoptosis / Q000187:drug effects*; D002292:Carcinoma, Renal Cell / Q000378:metabolism* / Q000473:pathology; D020169:Caspases / Q000378:metabolism; D045744:Cell Line, Tumor; D002470:Cell Survival / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D004721:Endoplasmic Reticulum / Q000187:drug effects / Q000378:metabolism; D000091342:Endoplasmic Reticulum Chaperone BiP; D004789:Enzyme Activation / Q000187:drug effects; D048049:Extracellular Signal-Regulated MAP Kinases / Q000378:metabolism; D006360:Heat-Shock Proteins / Q000378:metabolism; D006801:Humans; D007213:Indomethacin / Q000494:pharmacology*; D007680:Kidney Neoplasms / Q000378:metabolism* / Q000473:pathology; D048670:MAP Kinase Kinase 4 / Q000378:metabolism; D020935:MAP Kinase Signaling System / Q000187:drug effects; D020928:Mitogen-Activated Protein Kinases / Q000378:metabolism*; D018832:Molecular Chaperones / Q000378:metabolism; D018384:Oxidative Stress / Q000187:drug effects; D047492:Peroxisome Proliferator-Activated Receptors / Q000378:metabolism; D019869:Phosphatidylinositol 3-Kinases / Q000378:metabolism; D051057:Proto-Oncogene Proteins c-akt / Q000378:metabolism*; D017382:Reactive Oxygen Species / Q000378:metabolism; D013997:Time Factors; D051742:Transcription Factor CHOP / Q000378:metabolism; D015854:Up-Regulation; D048051:p38 Mitogen-Activated Protein Kinases / Q000378:metabolism
chemical_list: D051702:Activating Transcription Factor 6; D000894:Anti-Inflammatory Agents, Non-Steroidal; D000970:Antineoplastic Agents; D020169:Caspases; D000091342:Endoplasmic Reticulum Chaperone BiP; D048049:Extracellular Signal-Regulated MAP Kinases; D006360:Heat-Shock Proteins; D007213:Indomethacin; D048670:MAP Kinase Kinase 4; D020928:Mitogen-Activated Protein Kinases; D018832:Molecular Chaperones; D047492:Peroxisome Proliferator-Activated Receptors; D019869:Phosphatidylinositol 3-Kinases; D051057:Proto-Oncogene Proteins c-akt; D017382:Reactive Oxygen Species; D051742:Transcription Factor CHOP; D048051:p38 Mitogen-Activated Protein Kinases; C497111:ATF6 protein, human; C497249:DDIT3 protein, human; C000717247:HSPA5 protein, human