miRNA profiling of gastric epithelium from Pten mutant mouse

Phosphatase and tensin homologue deleted on chromosome 10 (PTEN) is a tumor suppressor that negatively regulates cell survival and proliferation by antagonizing phosphatidylinositol 3-kinase(PI3K)/protein kinase B(PKB/Akt) signaling. Loss of heterozygosity (LOH) of PTEN, reduced expression of PTEN and overexpression of phosphorylated Akt are frequently found in human gastric cancer, and their changes correlate with tumor progression and prognosis. Previous studies have shown that the deregulated miRNAs in human gastric cancer play important roles in gastric cancer cell proliferation, apoptosis and inflammation. However, miRNAs downstream PTEN/Akt signaling is poorly investigated. To clarify whether PTEN is involved in gastric tumorigenesis, we have generated a gastric epithelium specific PTEN knockout mouse which exhibited gastric tumor formation with enhanced cell proliferation.So the objectives of the microarray experiment were to, a) screen miRNAs which might be regulated by PTEN/Akt signaling by comparing the miRNA expression profiles between PTEN deficient and control gastric epithelia. 2) explore the microRNA mechanism involved in gastric cell proliferation and gastric tumorigenesis. miRNA profiling of mouse gastric epithelium,comparing Pten mutant mouse with controls. 4 samples. Experiments in 2 different time point, 20 days and 60 days after birth, 2 Biological replicates. Mutant tissue vs. controls from mixture of 3-4 mouse.第10号染色体缺失的磷酸酶与张力蛋白同源物（Phosphatase and tensin homologue deleted on chromosome 10，PTEN）是一类肿瘤抑制因子，可通过拮抗磷脂酰肌醇3-激酶（phosphatidylinositol 3-kinase，PI3K）/蛋白激酶B（protein kinase B，PKB/Akt）信号通路，负向调控细胞存活与增殖。PTEN的杂合性缺失（Loss of heterozygosity，LOH）、PTEN表达下调以及磷酸化Akt的过表达，在人胃癌组织中极为常见，且上述分子变化与肿瘤进展及预后密切相关。既往研究证实，人胃癌中失调的微小RNA（microRNA，miRNA）在胃癌细胞增殖、凋亡及炎症反应过程中发挥关键作用。然而，目前针对PTEN/Akt信号通路下游miRNA的相关研究仍较为匮乏。为明确PTEN是否参与胃肿瘤发生进程，我们构建了胃上皮特异性PTEN敲除小鼠模型，该模型可出现胃肿瘤形成，并伴随细胞增殖水平升高。因此本微阵列实验的研究目标为：1）通过比较PTEN缺陷型与对照胃上皮组织的miRNA表达谱，筛选可能受PTEN/Akt信号通路调控的miRNA；2）探究参与胃细胞增殖及胃肿瘤发生的miRNA作用机制。本实验通过检测小鼠胃上皮组织的miRNA表达谱，对比Pten突变型小鼠与野生型对照小鼠的差异。实验共纳入4个样本，设置2个不同时间点（出生后20天、60天），并设置2次生物学重复。突变型组织与对照组织均取自3-4只小鼠的混合组织。