0 273

Cited 19 times in

Epigenomic Promoter Alterations Amplify Gene Isoform and Immunogenic Diversity in Gastric Adenocarcinoma

 Aditi Qamra  ;  Manjie Xing  ;  Nisha Padmanabhan  ;  Jeffrey Jun Ting Kwok  ;  Shenli Zhang  ;  Chang Xu  ;  Yan Shan Leong  ;  Ai Ping Lee Lim  ;  Qianqao Tang  ;  Wen Fong Ooi  ;  Joyce Suling Lin  ;  Tannistha Nandi  ;  Xiaosai Yao  ;  Xuewen Ong  ;  Minghui Lee  ;  Su Ting Tay  ;  Angie Tan Lay Keng  ;  Erna Gondo Santoso  ;  Cedric Chuan Young Ng  ;  Alvin Ng  ;  Apinya Jusakul  ;  Duane Smoot  ;  Hassan Ashktorab  ;  Sun Young Rha  ;  Khay Guan Yeoh  ;  Wei Peng Yong  ;  Pierce K.H. Chow  ;  Weng Hoong Chan  ;  Hock Soo Ong  ;  Khee Chee Soo  ;  Kyoung-Mee Kim  ;  Wai Keong Wong  ;  Steven G. Rozen  ;  Bin Tean Teh  ;  Dennis Kappei  ;  Jeeyun Lee  ;  John Connolly  ;  Patrick Tan 
 CANCER DISCOVERY, Vol.7(6) : 630-651, 2017 
Journal Title
Issue Date
Adenocarcinoma/genetics* ; Cell Line, Tumor ; Epigenomics ; Humans ; Promoter Regions, Genetic* ; Stomach Neoplasms/genetics*
Promoter elements play important roles in isoform and cell type-specific expression. We surveyed the epigenomic promoter landscape of gastric adenocarcinoma, analyzing 110 chromatin profiles (H3K4me3, H3K4me1, H3K27ac) of primary gastric cancers, gastric cancer lines, and nonmalignant gastric tissues. We identified nearly 2,000 promoter alterations (somatic promoters), many deregulated in various epithelial malignancies and mapping frequently to alternative promoters within the same gene, generating potential pro-oncogenic isoforms (RASA3). Somatic promoter-associated N-terminal peptides displaying relative depletion in tumors exhibited high-affinity MHC binding predictions and elicited potent T-cell responses in vitro, suggesting a mechanism for reducing tumor antigenicity. In multiple patient cohorts, gastric cancers with high somatic promoter usage also displayed reduced T-cell cytolytic marker expression. Somatic promoters are enriched in PRC2 occupancy, display sensitivity to EZH2 therapeutic inhibition, and are associated with novel cancer-associated transcripts. By generating tumor-specific isoforms and decreasing tumor antigenicity, epigenomic promoter alterations may thus drive intrinsic tumorigenesis and also allow nascent cancers to evade host immunity.Significance: We apply epigenomic profiling to demarcate the promoter landscape of gastric cancer. Many tumor-specific promoters activate different promoters in the same gene, some generating pro-oncogenic isoforms. Tumor-specific promoters also reduce tumor antigenicity by causing relative depletion of immunogenic peptides, contributing to cancer immunoediting and allowing tumors to evade host immune attack.
Full Text
Appears in Collections:
1. College of Medicine (의과대학) > Dept. of Internal Medicine (내과학교실) > 1. Journal Papers
Yonsei Authors
Rha, Sun Young(라선영) ORCID logo https://orcid.org/0000-0002-2512-4531
사서에게 알리기


Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.