Artocarpin, an isoprenyl flavonoid, induces p53-dependent or independent apoptosis via ROS-mediated MAPKs and Akt activation in non-small cell lung cancer cells

Abstract

// Ming-Horng Tsai 1, * , Ju-Fang Liu 2, * , Yao-Chang Chiang 3, 4 , Stephen Chu-Sung Hu 5, 6 , Lee-Fen Hsu 7 , Yu-Ching Lin 7, 8, 9 , Zih-Chan Lin 10 , Hui-Chun Lee 1 , Mei-Chuan Chen 11 , Chieh-Liang Huang 3 , Chiang-Wen Lee 4, 12, 13, 14 1 Department of Pediatrics, Division of Neonatology and Pediatric Hematology/Oncology, Chang Gung Memorial Hospital, Yunlin, Taiwan 2 Central Laboratory, Shin-Kong Wu Ho-Su Memorial Hospital, Taipei, Taiwan 3 Center for Drug Abuse and Addiction, China Medical University Hospital, China Medical University, Taichung, Taiwan 4 Department of Nursing, Division of Basic Medical Sciences, Chang Gung University of Science and Technology, Chia-Yi, Taiwan 5 Department of Dermatology, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan 6 Department of Dermatology, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan 7 Department of Respiratory Care, Chang Gung University of Science and Technology, Chiayi Campus, Chiayi, Taiwan 8 Division of Pulmonary and Critical Care Medicine, Chang Gung Memorial Hospital, Chiayi, Taiwan 9 Department of Respiratory Care, Chang Gung University, Taoyuan, Taiwan 10 Graduate Institute of Biomedical Sciences, Chang Gung University, Taoyuan, Taiwan 11 Program for the Clinical Drug Discovery from Botanical Herbs, College of Pharmacy, Taipei Medical University, Taipei, Taiwan 12 Chronic Diseases and Health Promotion Research Center, Chang Gung University of Science and Technology, Chia-Yi, Taiwan 13 Research Center for Industry of Human Ecology and Research Center for Chinese Herbal Medicine, College of Human Ecology, Chang Gung University of Science and Technology, Taoyuan, Taiwan 14 Department of Rehabilitation, Chang Gung Memorial Hospital, Chia-Yi 61363, Taiwan * These authors contributed equally to this work Correspondence to: Chiang-Wen Lee, email: cwlee@mail.cgust.edu.tw Keywords: artocarpin, pro-oxidation, lung cancer, p53, apoptosis Received: June 15, 2016      Accepted: February 27, 2017      Published: March 09, 2017 ABSTRACT Artocarpin has been shown to exhibit cytotoxic effects on different cancer cells, including non-small cell lung carcinoma (NSCLC, A549). However, the underlying mechanisms remain unclear. Here, we explore both p53-dependent and independent apoptosis pathways in artocarpin-treated NSCLC cells. Our results showed that artocarpin rapidly induced activation of cellular protein kinases including Erk1/2, p38 and Akt S473 . Inhibition of these protein kinases prevented artocarpin-induced cell death. Moreover, artocarpin-induced phosphorylation of these protein kinases and apoptosis were mediated by induction of reactive oxygen species (ROS), as pretreatment with NAC (a ROS scavenger) and Apocynin (a Nox-2 inhibitor) blocked these events. Similarly, transient transfection of p47 Phox or p91 Phox siRNA attenuated artocarpin-induced NADPH oxidase activity and cell death. In addition, p53 dependent apoptotic proteins including PUMA, cytochrome c, Apaf-1 and caspase 3 were activated by artocarpin, and these effects can be abolished by antioxidants, MAPK inhibitors (U0126 and SB202190), but not by PI3K inhibitor (LY294002). Furthermore, we found that artocarpin-induced Akt phosphorylation led to increased NF-κB activity, which may act as an upstream regulator in the c-Myc and Noxa pathway. Therefore, we propose that enhancement of both ERK/ p38/ p53-dependent or independent Akt S473 /NF-κB/c-Myc/Noxa cascade by Nox-derived ROS generation plays an important role in artocarpin-induced apoptosis in NSCLC cells.