PMID- 26409771 OWN - NLM STAT- MEDLINE DCOM- 20160922 LR - 20181202 IS - 1873-4596 (Electronic) IS - 0891-5849 (Linking) VI - 89 DP - 2015 Dec TI - Vorinostat synergizes with EGFR inhibitors in NSCLC cells by increasing ROS via up-regulation of the major mitochondrial porin VDAC1 and modulation of the c-Myc-NRF2-KEAP1 pathway. PG - 287-99 LID - S0891-5849(15)00519-5 [pii] LID - 10.1016/j.freeradbiomed.2015.07.155 [doi] AB - In non-small-cell lung cancer (NSCLC) patients, the activation of alternative pathways contributes to the limited efficacy of the epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) gefitinib and erlotinib. The present study examines a panel of EGFR wild-type, K-Ras mutated, NSCLC lines, which were all intrinsically resistant to EGFR-TKIs, and demonstrates that the histone deacetylase inhibitor vorinostat can improve the therapeutic efficacy of gefitinib or erlotinib, inducing strong synergistic antiproliferative and pro-apoptotic effects that are paralleled by reactive oxygen species accumulation and by increased DNA damage. By knockdown experiments, we suggested that the up-regulation of voltage-dependent anion-selective channel protein 1 (VDAC1), the major mitochondrial porin of the outer mitochondrial membrane, which was induced by vorinostat and further increased by the combination, could be functionally involved in oxidative stress-dependent apoptosis. Significantly, we also observed the attenuation of the expression of both the enzyme hexokinase1, a negative VDAC1 regulator, and the anti-apoptotic porin VDAC2, only in the combination setting, suggesting convergent mechanisms that enhanced mitochondria-dependent apoptosis by targeting VDAC protein functions. Furthermore, the prosurvival capacities of the cells were also inhibited by the combination treatments, as shown by complete pAKT deactivation, increased GSK3beta expression, and c-Myc down-regulation. Finally, we observed that the combination treatment of vorinostat and either of the EGFR-TKIs induced the down-regulation of the c-Myc-regulated nuclear factor erythroid 2-related factor 2 (NRF2) transcription factor and the up-regulation of the NRF2 repressor Kelch-like ECH-associated protein 1 regulator (KEAP1). These two genes are crucial for the redox stress response, often dysfunctional in NSCLC, and involved in EGFR-TKI resistance. Taken together, these results are the first to demonstrate that altering redox homeostasis is a new mechanism underlying the observed synergism between vorinostat and EGFR TKIs in NSCLC. CI - Copyright (c) 2015 Elsevier Inc. All rights reserved. FAU - Leone, Alessandra AU - Leone A AD - Experimental Pharmacology Unit, Istituto Nazionale Tumori Fondazione G. Pascale-IRCCS, 80131 Naples, Italy. FAU - Roca, Maria Serena AU - Roca MS AD - Experimental Pharmacology Unit, Istituto Nazionale Tumori Fondazione G. Pascale-IRCCS, 80131 Naples, Italy. FAU - Ciardiello, Chiara AU - Ciardiello C AD - Experimental Pharmacology Unit, Istituto Nazionale Tumori Fondazione G. Pascale-IRCCS, 80131 Naples, Italy. FAU - Terranova-Barberio, Manuela AU - Terranova-Barberio M AD - Experimental Pharmacology Unit, Istituto Nazionale Tumori Fondazione G. Pascale-IRCCS, 80131 Naples, Italy. FAU - Vitagliano, Carlo AU - Vitagliano C AD - Experimental Pharmacology Unit, Istituto Nazionale Tumori Fondazione G. Pascale-IRCCS, 80131 Naples, Italy. FAU - Ciliberto, Gennaro AU - Ciliberto G AD - Scientific Direction, Istituto Nazionale Tumori Fondazione G. Pascale-IRCCS, 80131 Naples, Italy. FAU - Mancini, Rita AU - Mancini R AD - Department of Surgery "P.Valdoni" and Department of Clinical and Molecular Medicine, La Sapienza University, 00161 Rome, Italy. FAU - Di Gennaro, Elena AU - Di Gennaro E AD - Experimental Pharmacology Unit, Istituto Nazionale Tumori Fondazione G. Pascale-IRCCS, 80131 Naples, Italy. FAU - Bruzzese, Francesca AU - Bruzzese F AD - Experimental Pharmacology Unit, Istituto Nazionale Tumori Fondazione G. Pascale-IRCCS, 80131 Naples, Italy. FAU - Budillon, Alfredo AU - Budillon A AD - Experimental Pharmacology Unit, Istituto Nazionale Tumori Fondazione G. Pascale-IRCCS, 80131 Naples, Italy. Electronic address: a.budillon@istitutotumori.na.it. LA - eng PT - Journal Article PT - Research Support, Non-U.S. Gov't DEP - 20150926 PL - United States TA - Free Radic Biol Med JT - Free radical biology & medicine JID - 8709159 RN - 0 (Hydroxamic Acids) RN - 0 (Intracellular Signaling Peptides and Proteins) RN - 0 (KEAP1 protein, human) RN - 0 (Kelch-Like ECH-Associated Protein 1) RN - 0 (MYC protein, human) RN - 0 (NF-E2-Related Factor 2) RN - 0 (NFE2L2 protein, human) RN - 0 (Protein Kinase Inhibitors) RN - 0 (Proto-Oncogene Proteins c-myc) RN - 0 (Quinazolines) RN - 0 (RNA, Messenger) RN - 0 (Reactive Oxygen Species) RN - 0 (VDAC1 protein, human) RN - 58IFB293JI (Vorinostat) RN - EC 1.6.- (Voltage-Dependent Anion Channel 1) RN - EC 2.7.10.1 (EGFR protein, human) RN - EC 2.7.10.1 (ErbB Receptors) RN - S65743JHBS (Gefitinib) SB - IM MH - Apoptosis/drug effects MH - Blotting, Western MH - Carcinoma, Non-Small-Cell Lung/*drug therapy/metabolism/pathology MH - Cell Movement/drug effects MH - Cell Proliferation/drug effects MH - *Drug Synergism MH - ErbB Receptors/*antagonists & inhibitors MH - Gefitinib MH - Gene Expression Regulation, Neoplastic/*drug effects MH - Humans MH - Hydroxamic Acids/*pharmacology MH - Intracellular Signaling Peptides and Proteins/genetics/metabolism MH - Kelch-Like ECH-Associated Protein 1 MH - Lung Neoplasms/drug therapy/metabolism/pathology MH - NF-E2-Related Factor 2/genetics/metabolism MH - Protein Kinase Inhibitors/pharmacology MH - Proto-Oncogene Proteins c-myc/genetics/metabolism MH - Quinazolines/pharmacology MH - RNA, Messenger/genetics MH - Reactive Oxygen Species/*metabolism MH - Real-Time Polymerase Chain Reaction MH - Reverse Transcriptase Polymerase Chain Reaction MH - Tumor Cells, Cultured MH - Voltage-Dependent Anion Channel 1/genetics/*metabolism MH - Vorinostat OTO - NOTNLM OT - EGFR tyrosine kinase inhibitors OT - HDACi OT - KEAP1 OT - NRF2 OT - NSCLC cancer OT - Oxidative stress OT - ROS OT - VDAC1 EDAT- 2015/09/28 06:00 MHDA- 2016/09/23 06:00 CRDT- 2015/09/28 06:00 PHST- 2015/02/26 00:00 [received] PHST- 2015/07/17 00:00 [revised] PHST- 2015/07/19 00:00 [accepted] PHST- 2015/09/28 06:00 [entrez] PHST- 2015/09/28 06:00 [pubmed] PHST- 2016/09/23 06:00 [medline] AID - S0891-5849(15)00519-5 [pii] AID - 10.1016/j.freeradbiomed.2015.07.155 [doi] PST - ppublish SO - Free Radic Biol Med. 2015 Dec;89:287-99. doi: 10.1016/j.freeradbiomed.2015.07.155. Epub 2015 Sep 26.