AKT2 was the only gene (of 44 genes) harboring 2 nonsynonymous point mutations identified in AGS–EBV cells. AKT2 mutation was also the highest in frequency and associated most significantly with primary EBV(+) gastric cancer as compared with EBV(-) gastric cancer. Importantly, we further confirmed that mutations in AKT2 KU-60019 mouse were associated with reduced survival in EBV(+) gastric cancer patients. Interestingly,
AKT2 is also the only gene involved in 2 of the 5 core pathways (focal adhesion and MAPK signaling). The mutant form of AKT2 identified in AGS–EBV possessed higher kinase activity, increased activities of the important mediators of the MAPK signaling pathway (AP-1 and ERK), and exerted a promoting effect on cell growth as compared with wild-type AKT2 ( Figure 6). All these findings emphasize the importance of AKT2 in connection with EBV(+) gastric cancer. In summary, as shown in Figure 7, this study systematically showed STI571 cell line the EBV-associated genomic and epigenomic alterations in gastric cancer. Expression of EBV genes in gastric cancer was shown by transcriptome analysis of the EBV-infected cell model and further confirmed in EBV(+) primary gastric cancers. Whole-genome sequencing showed EBV-associated host mutations in genes such as AKT2, CCNA1, MAP3K4, and TGFBR1, and mutations in AKT2 are associated with reduced survival times of patients with EBV(+) gastric cancer. Epigenome analysis uncovered hypermethylation of genes including
ACSS1, IHH, FAM3B, and TRABD through EBV triclocarban infection. Five core pathways were shown to be dysregulated by EBV-associated host genomic and epigenomic aberrations in gastric cancer. Moreover, the functional importance of selected genes (IHH, TRABD, and AKT2) and pathway (MAPK) were shown further. These findings provide a
systematic view of EBV-associated host genomic and epigenomic abnormalities and signaling networks that may govern the pathogenesis of EBV-associated gastric cancer. Sequencing data deposition: all sequencing data from this study have been deposited in the NCBI Sequence Read Archive (http://www.ncbi.nlm.nih.gov/sra); accession number: SRA067982. “
“Mark W. Babyatsky, MD Jeffrey S. Ben-Zvi, MD, FASGE Fernando Bermudez, MD John R. Bingham, FRCP Melvin Lewis Bram, MD Albert T. Chan, MD Arlette Darfeuille-Michaud, PhD Michael Field, MD Michael T. Foley, MD Franz Goldstein, MD Thomas R. Hendrix, MD Herbert L. Hyman, MD Orlyn O. Lockard, MD Leon Morgenstern, MD Owen J. Smith, MD Ben H. Sullivan Jr., MD, FASGE Joseph G. Sweeting, MD John H. Weisburger, MD, PhD “
“The stomach is divided into 3 regions: the forestomach (in mice) or cardia (in human beings), the corpus, and the pyloric antrum. The stomach lumen is lined with a monolayer of epithelial cells that is organized in flask-like invaginations, each of which consists of several glands that feed into a single luminal pit. The epithelium constantly renews itself and the stem cells fueling this process reside in the gastric glands.