Dataset Information

High Levels of Class I Major Histocompatibility Complex mRNA Are Present in Epstein-Barr Virus-Associated Gastric Adenocarcinomas.

ABSTRACT: Epstein-Barr virus (EBV) is responsible for approximately 9% of stomach adenocarcinomas. EBV-encoded microRNAs have been reported as reducing the function of the class I major histocompatibility complex (MHC-I) antigen presentation apparatus, which could allow infected cells to evade adaptive immune responses. Using data from nearly 400 human gastric carcinomas (GCs), we assessed the impact of EBV on MHC-I heavy and light chain mRNA levels, as well as multiple other components essential for antigen processing and presentation. Unexpectedly, mRNA levels of these genes were as high, or higher, in EBV-associated gastric carcinomas (EBVaGCs) compared to normal control tissues or other GC subtypes. This coordinated upregulation could have been a consequence of the higher intratumoral levels of interferon ? in EBVaGCs, which correlated with signatures of increased infiltration by T and natural killer (NK) cells. These results indicate that EBV-encoded products do not effectively reduce mRNA levels of the MHC-I antigen presentation apparatus in human GCs.

SUBMITTER: Ghasemi F

PROVIDER: S-EPMC7072773 | biostudies-literature | 2020 Feb

REPOSITORIES: biostudies-literature

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High Levels of Class I Major Histocompatibility Complex mRNA Are Present in Epstein-Barr Virus-Associated Gastric Adenocarcinomas.

Ghasemi Farhad F Gameiro Steven F SF Tessier Tanner M TM Maciver Allison H AH Mymryk Joe S JS

Cells 20200221 2

Epstein-Barr virus (EBV) is responsible for approximately 9% of stomach adenocarcinomas. EBV-encoded microRNAs have been reported as reducing the function of the class I major histocompatibility complex (MHC-I) antigen presentation apparatus, which could allow infected cells to evade adaptive immune responses. Using data from nearly 400 human gastric carcinomas (GCs), we assessed the impact of EBV on MHC-I heavy and light chain mRNA levels, as well as multiple other components essential for anti ...[more]

PMID: 32098275

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Dataset Information

High Levels of Class I Major Histocompatibility Complex mRNA Are Present in Epstein-Barr Virus-Associated Gastric Adenocarcinomas.

Publications

High Levels of Class I Major Histocompatibility Complex mRNA Are Present in Epstein-Barr Virus-Associated Gastric Adenocarcinomas.

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