Whole genome expression profiling of gastric high-grade intraepithelial neoplasia with or without cancer.

Objective: To investigate the whole genome expression profiles between gastric high-grade intraepithelial neoplasia (HGIN) tissues with cancer and HGIN tissues without cancer.

Methods: Gastric specimens from an upper magnifying chromoendoscopic targeted biopsy were collected at Peking Union Medical College Hospital from March 2010 to May 2013. Each of the forceps biopsies from the 21 patients was HGIN,but there were 10 HGIN and 11 HGIN with cancer after the endoscopic submucosal dissection. The whole genome expression profiling was performed on 10 HGIN samples and 11 HGIN with cancer samples using Agilent 4 × 44K Whole Human Genome microarrays. Differentially expressed genes between different types of lesions were identified using an unpaired t-test and corrected with the Benjamini and Hochberg false discovery rate algorithm. A gene ontology(GO)enrichment analysis was performed using the GeneSpring software GX 12.6.

Results: The gene expression patterns were different between HGIN tissues with cancer and HGIN tissues without cancer. There were 470 significantly differentially expressed transcripts between them (P<0.05,Fold Change>2), with 180 up-regulated genes and 290 down-regulated genes in HGIN tissues with cancer. A GO enrichment analysis demonstrated that the most striking over-expressed transcripts in HGIN with cancer were in the category of triglyceride biosynthetic process,acylglycerol biosynthetic process,neutral lipid biosynthetic process,glycerol ether metabolic process,organic ether metabolic process,and glycerolipid metabolic process.

Conclusion: The change of lipid metabolism may contribute to the pathogenesis of gastric cancer at an early stage.