Abstract

Enriched PD-L1 expression in cancer stem-like cells (CSCs) contributes to CSC immune evasion. However, the mechanisms underlying PD-L1 enrichment in CSCs remain unclear. Here, we demonstrate that epithelial–mesenchymal transition (EMT) enriches PD-L1 in CSCs by the EMT/β-catenin/STT3/PD-L1 signaling axis, in which EMT transcriptionally induces N-glycosyltransferase STT3 through β-catenin, and subsequent STT3-dependent PD-L1 N-glycosylation stabilizes and upregulates PD-L1. The axis is also utilized by the general cancer cell population, but it has much more profound effect on CSCs as EMT induces more STT3 in CSCs than in non-CSCs. We further identify a non-canonical mesenchymal–epithelial transition (MET) activity of etoposide, which suppresses the EMT/β-catenin/STT3/PD-L1 axis through TOP2B degradation-dependent nuclear β-catenin reduction, leading to PD-L1 downregulation of CSCs and non-CSCs and sensitization of cancer cells to anti-Tim-3 therapy. Together, our results link MET to PD-L1 stabilization through glycosylation regulation and reveal it as a potential strategy to enhance cancer immunotherapy efficacy.

Details

Title
STT3-dependent PD-L1 accumulation on cancer stem cells promotes immune evasion
Author
Jung-Mao, Hsu 1 ; Xia, Weiya 1 ; Hsu, Yi-Hsin 1 ; Li-Chuan, Chan 2 ; Wen-Hsuan Yu 2 ; Jong-Ho, Cha 3 ; Chen, Chun-Te 1 ; Hsin-Wei Liao 4 ; Chu-Wei, Kuo 5 ; Kay-Hooi Khoo 5 ; Hsu, Jennifer L 6 ; Chia-Wei, Li 1 ; Seung-Oe Lim 1 ; Shih-Shin, Chang 2 ; Yi-Chun, Chen 1 ; Guo-xin, Ren 7 ; Mien-Chie Hung 8 

 Department of Molecular and Cellular Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA 
 Department of Molecular and Cellular Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA; The University of Texas Graduate School of Biomedical Sciences at Houston, Houston, TX, USA 
 Department of Molecular and Cellular Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA; Tumor Microenvironment Global Core Research Center, College of Pharmacy, Seoul National University, Seoul, Korea 
 Department of Molecular and Cellular Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA; The University of Texas Graduate School of Biomedical Sciences at Houston, Houston, TX, USA; Center for Systems Biology, Massachusetts General Hospital Research Institute, Harvard Medical School, Boston, MA, USA 
 Institute of Biological Chemistry, Academia Sinica, Taipei, Taiwan 
 Department of Molecular and Cellular Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA; Graduate Institute of Biomedical Sciences and Center for Molecular Medicine, China Medical University, Taichung, Taiwan 
 Department of Oral and Maxillofacial, Head and Neck Oncology, Affiliated 9th People’s Hospital, School of Medicine, Shanghai Jiaotong University, Shanghai, China 
 Department of Molecular and Cellular Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA; The University of Texas Graduate School of Biomedical Sciences at Houston, Houston, TX, USA; Graduate Institute of Biomedical Sciences and Center for Molecular Medicine, China Medical University, Taichung, Taiwan; Department of Biotechnology, Asia University, Taichung, Taiwan 
Pages
1-17
Publication year
2018
Publication date
May 2018
Publisher
Nature Publishing Group
e-ISSN
20411723
Source type
Scholarly Journal
Language of publication
English
ProQuest document ID
2039258465
Copyright
© 2018. This work is published under http://creativecommons.org/licenses/by/4.0/ (the “License”). Notwithstanding the ProQuest Terms and Conditions, you may use this content in accordance with the terms of the License.