Open AccessTargeting autophagy potentiates antitumor activity of Met-TKIs against Met-amplified gastric cancer
Author(s) -
Xun Lin,
Zhi Peng,
Xiaojuan Wang,
Jianling Zou,
Dongshao Chen,
Zuhua Chen,
Zhongwu Li,
Bin Dong,
Jing Gao,
Lin Shen
Publication year - 2019
Publication title -
cell death and disease
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.482
H-Index - 111
ISSN - 2041-4889
DOI - 10.1038/s41419-019-1314-x
Subject(s) - autophagy , pi3k/akt/mtor pathway , cancer research , ulk1 , bafilomycin , pharmacology , medicine , apoptosis , kinase , biology , microbiology and biotechnology , signal transduction , protein kinase a , biochemistry , ampk
Met tyrosine kinase inhibitors (Met-TKIs) subjected to ongoing clinical trials are a promising option for Met-amplified gastric cancer (GC), but how to optimize their antitumor activity especially with combination schemes remains unclear. Since autophagy is known to be initiated by Met-TKIs, we investigated its underlying mechanisms and therapeutic potentials of Met-TKIs combined with autophagy inhibitors against Met-amplified GC. As expected, four Met-TKIs induced autophagy in Met-amplified GC cells marked by p62 degradation, LC3-II accumulation and increased LC3-positive puncta. Autophagy flux activation by Met-TKIs was further validated with combined lysosomal inhibitors, bafilomycin A1 (Baf A1) and hydroxychloroquine (HCQ). Molecular investigations reveal that autophagy induction along with mTOR and ULK1 de-phosphorylation upon Met-TKI treatment could be relieved by hepatocyte growth factor (HGF) and mTOR agonist MHY1485 (MHY), suggesting that autophagy was initiated by Met-TKIs via Met/mTOR/ULK1 cascade. Intriguingly, Met-TKIs further suppressed cell survival and tumor growth in the presence of autophagy blockade in Met-amplified GC preclinical models. Thus, these findings indicate Met/mTOR/ULK1 cascade responsible for Met-TKI-mediated autophagy and Met-TKIs combined with autophagy inhibitors as a promising choice to treat Met-amplified GC.