Back to Search Start Over

Hedgehog pathway maintains cell survival under stress conditions, and drives drug resistance in lung adenocarcinoma

Authors :
Cheng-Wen Wu
Erh-Hsuan Lin
Sheng-Ping Yang
Ting-Yu Kuo
Yu-Rung Kao
Teh Ying Chou
Chih-An Lin
Chiung-Fang Hsu
Chao-Chi Ho
Source :
Oncotarget
Publication Year :
2016
Publisher :
Impact Journals, LLC, 2016.

Abstract

// Erh-Hsuan Lin 1, 2, 3, 4 , Yu-Rung Kao 1 , Chih-An Lin 5 , Ting-Yu Kuo 4 , Sheng-Ping Yang 2 , Chiung-Fang Hsu 1 , Teh-Ying Chou 3, 6 , Chao-Chi Ho 7 , Cheng-Wen Wu 1, 2, 3, 4 1 Institute of Biomedical Sciences, Academia Sinica, Taipei, Taiwan 2 Institute of Microbiology and Immunology, National Yang Ming University, Taipei, Taiwan 3 Institute of Clinical Medicine, National Yang-Ming University, Taipei, Taiwan 4 Institute of Biochemistry and Molecular Biology, National Yang Ming University, Taipei, Taiwan 5 Department of Clinical Laboratory Sciences and Medical Biotechnology, National Taiwan University Medical College, Taipei, Taiwan 6 Department of Pathology and Laboratory Medicine, Taipei Veterans General Hospital, Taipei, Taiwan 7 Department of Internal Medicine, National Taiwan University Hospital and National Taiwan University Medical College, Taipei, Taiwan Correspondence to: Cheng-Wen Wu, e-mail: cwwu@ym.edu.tw Keywords: lung adenocarcinoma, Hedgehog pathway, HHIP, drug resistance, HGF/MET Received: July 30, 2015 Accepted: March 02, 2016 Published: March 22, 2016 ABSTRACT Hedgehog (HH) pathway plays an important role in embryonic development, but is largely inactive in adult except for tissue repair. Aberrant activation of HH pathway has been found in a variety of cancer types. In non-small cell lung cancer, however, the role and importance of HH pathway remain controversial. In the current study, we found that HH pathway was maintained in low activity in lung adenocarcinoma (LAC) cells under normal culture condition, but was highly induced in response to stress conditions. Activation of HH pathway promoted cell survival, growth, and invasion partially through HGF and MET signaling. Hedgehog-Interacting Protein (HHIP), a cell-surface negative regulator of HH pathway, was epigenetically silenced in LAC. Overexpression of HHIP blocked the activation of HH and HGF/MET pathways, and made cells significantly more susceptible to stress conditions. In LAC cells with acquired resistance to Epidermal Growth Factor Receptor Tyrosin Kinase Inhibitor (EGFR-TKI), we found that a part of tumor cells were much more sensitive to HH or HGF/MET inhibitors, suggesting an oncogenic addiction shift from EGFR to HH and HGF/MET pathways. In conclusion, this study showed that HH pathway is a survival signaling that drives LAC cell growth under stress conditions, and HHIP is a key regulator to block the induction of HH pathway. Targeting the HH pathway through inhibitors or HHIP thus holds promise to address EGFR-TKI resistance in LAC in clinic.

Details

ISSN :
19492553
Volume :
7
Database :
OpenAIRE
Journal :
Oncotarget
Accession number :
edsair.doi.dedup.....2144e7a17ae5a2de56a0a8460c586452
Full Text :
https://doi.org/10.18632/oncotarget.8253