miRNA expression from gp130F/F mice antrum at 4 weeks of age

The molecular events promoting the initiation of gastric cancer (GC), the third most lethal cancer worldwide, are ill-defined. Here, we demonstrate that upregulation of miR-200 family members is associated with tumor initiation in the gp130F/F mouse model of early GC. The onset of gastric inflammation-associated adenomatous hyperplasia in gp130F/F mice occurs at ~6 weeks of age, with established intestinal-type tumors (3 months of age) progressively growing until a maximum size is reached at 6 months of age, with some evidence of carcinoma in situ. Since this phenotype histologically mimics early stage human GC, we therefore utilized gp130F/F mice as a model to identify miRNAs involved in the initiating molecular events leading to early stage GC. For this purpose, we performed miRNA microarrays on mouse gastric antrum tissue from gp130F/F and sex-matched littermate wild-type (gp130+/+) control mice aged 4 weeks; this age was chosen since antrum tissue from 4 week old (wo) gp130F/F mice is devoid of any histological signs of inflammation or hyperplasia, and is thus comparable to wild-type gastric antrum tissue Total RNA from 4 week old mouse antrum samples was subjected to an Affymetrix miRNA 2.0 array which included 722 mouse mature miRNAs and 690 mouse pre-miRNAs (Affymetrix).