Exploration of possible different molecules between EBV associated and non-associated gastric cancer by omics / 基础医学与临床

ABSTRACT

Objective To identify molecular differences between EBVaGC and EBCnGC by omics to provide a basis for treatment options of EBVaGC. Methods Chromogenic in situ hybridization was used to detect EBV RNA status of surgical specimens and PDXs. Targeted capture sequencing and protein mass spectrometry were implemented to analyze the different molecules, verify the PD-L1 expression by immunochemistry in EBV positive and negative tis-sues. Results Compared with EBVnGC, the higher PIK3CA mutation rate and lower TP53 mutation rate were found in EBVaGC. Post-transcriptional regulation molecules were up-regulated and molecules associated with me-tabolism and oxidative phosphorylation were down-regulated in EBVaGC. PD-L1 expression in EBV positive PDXs was significantly higher than that in EBV negative (76.92% vs 25.0%, P＜0.05). Conclusions There is a great difference between EBVaGC and EBVnGC on genetic variation and expression, which provides the basis for further exploration of the molecular mechanism and treatment strategy of EBVaGC.