gene expression profiling of mouse model of Helicobacter-induced gastric cancer

We have previously reported human gastrin overexpressing transgenic mice (=INS-GAS mice) and Helicobacter felis (=H.felis) infection synergistically accelerated gastric cancer in mice stomachs. (Wang et al 2000) Using this mouse model, we employed microarray analysis of gene expression profiling to identify gastric cancer-specific genes. Keywords: disease state analysis 30 male INS-GAS mice (FVB/N background) were divided into groups: 15 mice were infected with H.felis at the age of 2-3 months and another 15 mice were not infected. 30 male non-transgenic FVB/N mice were also divided into 2 groups: 15 mice were infected with H.felis at the age of 2-3 months and another 15 mice were not infected. All mice were sacrificed after 6 months of H.felis infection, and total RNAs were extracted from whole stomachs. Histological analysis confirmed all of the stomachs in H.felis infected INS-GAS mice (=INSGAS+Hf) had intra-epithelial gastric cancer, and some of them also had invasion into submucosa, but none of them had distant metastatic lesions. Other 3 control groups had following histology in stomachs. (1) non-transgenic mice with H.felis infection (=FVB+Hf): severe intestinal metaplasia and/or mild dysplasia. (2) INS-GAS mice without infection (=INSGAS wt): severe atrophic gastritis and/or mild intestinal metaplasia (3) non-transgenic mice without infection (=FVB wt): normal stomach. Total RNAs extracted from each mouse in 4 different groups were used for microarray analysis of Affymetrix GeneChip. Up- or down-regulated genes in INSGAS+Hf group compared with all 3 control groups (FVB+HF, INSGAS wt and FVB wt) may represent gastric cancer-specific genes.