title: Afatinib induces apoptosis in NSCLC without EGFR mutation through Elk-1-mediated suppression of CIP2A.
abstract: Afatinib has anti-tumor effect in non-small cell lung carcinoma (NSCLC) with epidermal growth factor receptor (EGFR) mutation. We found afatinib can also induce apoptosis in NSCLC cells without EGFR mutation through CIP2A pathway. Four NSCLC cell lines (H358 H441 H460 and A549) were treated with afatinib to determine their sensitivity to afatinib-induced cell death and apoptosis. The effects of CIP2A on afatinib-induced apoptosis were confirmed by overexpression and knockdown of CIP2A expression in the sensitive and resistant cells, respectively. Reduction of Elk-1 binding to the CIP2A promoter and suppression of CIP2A transcription were analyzed. In vivo efficacy of afatinib against H358 and H460 xenografts tumors were also determined in nude mice. Afatinib induced significant cell death and apoptosis in H358 and H441 cells, but not in H460 or A549 cells. The apoptotic effect of afatinib in sensitive cells was associated with downregulation of CIP2A, promotion of PP2A activity and decrease in AKT phosphorylation. Afatinib suppressed CIP2A at the gene transcription level by reducing the promoter binding activity of Elk-1. Clinical samples showed that higher CIP2A expression predicted a poor prognosis and Elk-1 and CIP2A expressions were highly correlated. In conclusion, afatinib induces apoptosis in NSCLC without EGFR mutations through Elk-1/CIP2A/PP2A/AKT pathway.
authors.affiliation: Medical Research Center, Cardinal Tien Hospital, School of Medicine, Fu Jen Catholic University, New Taipei City, Taiwan.
authors.forename: Ting-Ting
authors.initials: TT
authors.lastname: Chao
authors.affiliation: Medical Research Center, Cardinal Tien Hospital, School of Medicine, Fu Jen Catholic University, New Taipei City, Taiwan.|Department of Internal Medicine, Cardinal Tien Hospital, School of Medicine, Fu Jen Catholic University, New Taipei City, Taiwan.|Graduate Institute of Clinical Medicine, College of Medicine, National Taiwan University, Taipei, Taiwan.
authors.forename: Cheng-Yi
authors.initials: CY
authors.lastname: Wang
authors.affiliation: Department of Pathology, Cardinal Tien Hospital, School of Medicine, Fu Jen Catholic University, New Taipei City, Taiwan.
authors.forename: Yen-Lin
authors.initials: YL
authors.lastname: Chen
authors.affiliation: Department of Intensive Care Medicine, Chi Mei Medical Center, Liouying, Tainan, Taiwan.
authors.forename: Chih-Cheng
authors.initials: CC
authors.lastname: Lai
authors.affiliation: Medical Research Center, Cardinal Tien Hospital, School of Medicine, Fu Jen Catholic University, New Taipei City, Taiwan.
authors.forename: Fang-Yu
authors.initials: FY
authors.lastname: Chang
authors.affiliation: Medical Research Center, Cardinal Tien Hospital, School of Medicine, Fu Jen Catholic University, New Taipei City, Taiwan.
authors.forename: Yi-Ting
authors.initials: YT
authors.lastname: Tsai
authors.affiliation: Instrumentation Resource Center, National Yang-Ming University, Taipei, Taiwan.
authors.forename: Chung-Hao H
authors.initials: CH
authors.lastname: Chao
authors.affiliation: Institute of Biopharmaceutical Sciences, National Yang-Ming University, Taipei, Taiwan.
authors.forename: Chung-Wai
authors.initials: CW
authors.lastname: Shiau
authors.affiliation: Department of Medicine, Duke University Medical Center, Durham, North Carolina, USA.
authors.forename: Yuh-Chin T
authors.initials: YC
authors.lastname: Huang
authors.affiliation: Department of Internal Medicine, National Taiwan University Hospital and National Taiwan University, Taipei, Taiwan.
authors.forename: Chong-Jen
authors.initials: CJ
authors.lastname: Yu
authors.affiliation: Department of Medical Research, National Taiwan University Hospital, Taipei, Taiwan.|National Center of Excellence for Clinical Trial and Research, National Taiwan University Hospital, Taipei, Taiwan.
authors.forename: Kuen-Feng
authors.initials: KF
authors.lastname: Chen
mesh_terms: D000077716:Afatinib; D000368:Aged; D000818:Animals; D017209:Apoptosis / Q000187:drug effects*; D001324:Autoantigens / Q000235:genetics* / Q000378:metabolism; D002289:Carcinoma, Non-Small-Cell Lung / Q000188:drug therapy* / Q000235:genetics / Q000378:metabolism; D045744:Cell Line, Tumor; D066246:ErbB Receptors / Q000235:genetics / Q000378:metabolism; D005260:Female; D015972:Gene Expression Regulation, Neoplastic / Q000187:drug effects; D006801:Humans; D047908:Intracellular Signaling Peptides and Proteins; D053208:Kaplan-Meier Estimate; D008175:Lung Neoplasms / Q000188:drug therapy* / Q000235:genetics / Q000378:metabolism; D008297:Male; D008565:Membrane Proteins / Q000235:genetics* / Q000378:metabolism; D008819:Mice, Nude; D008875:Middle Aged; D009154:Mutation; D011401:Promoter Regions, Genetic / Q000235:genetics; D011485:Protein Binding / Q000187:drug effects; D054648:Protein Phosphatase 2 / Q000235:genetics / Q000378:metabolism; D051057:Proto-Oncogene Proteins c-akt / Q000235:genetics / Q000378:metabolism; D011799:Quinazolines / Q000494:pharmacology*; D034622:RNA Interference; D020133:Reverse Transcriptase Polymerase Chain Reaction; D023041:Xenograft Model Antitumor Assays; D050807:ets-Domain Protein Elk-1 / Q000235:genetics* / Q000378:metabolism
chemical_list: D001324:Autoantigens; C500266:CIP2A protein, human; D047908:Intracellular Signaling Peptides and Proteins; D008565:Membrane Proteins; D011799:Quinazolines; D050807:ets-Domain Protein Elk-1; D000077716:Afatinib; D066246:ErbB Receptors; D051057:Proto-Oncogene Proteins c-akt; D054648:Protein Phosphatase 2