Identification of tumor suppressor genes involved in multi-step gastrointestinal carcinogenesis

多步胃肠癌发生过程中抑癌基因的鉴定

基本信息

批准号：
10470131
负责人：
ABURATANI Hiroyuki
金额：
$ 8.58万
依托单位：
The University of Tokyo
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (B)
财政年份：
1998
资助国家：
日本
起止时间：
1998 至 2000
项目状态：
已结题

项目摘要

We aimed to identify tumor suppressor genes involved in multi-step gastrointestinal carcinogenesis through genome-wide scanning of alteration in either DNA or RNA levels in tumor. First, Representational Difference Analysis (RDA) was applied to identify homozygously deleted chromosomal regions in tumor cells, which could be putative tumor suppressor loci. In the stomach cancer cell line OCUM-2MD3, prone to peritoneal dissemination, three chromosomal loci, 1p, 3pl4 and 16q22, were found to be homozygously deleted. Putative tumor suppressor genes, FHJT and WWOX, are located in the 3p and 16q deletion, respectively, while a novel gene, ZAP1, was isolated from 1p deletion, and its aberrant transcripts were found in various cancer cell lines. Secondly, DNA chip analysis was performed to monitor altered expression profiles of thousands of genes. In 2MD3 cell, genes specific for squamous cell lineage were up-regulated, while MHC class II genes were up-regulated in 2MLN cell line. In primary gastric cancers genes discriminating between cancer and non-cancer, or between metastasis (+) and (-) have been identified. Genes involved in de-differentiation of liver tumors were also obtained and utilized to classify differentiation grades of liver cancers. Nonparametric statistical analysis, like Kruskal-Wallis test, and non-hierarchial clustering were also very useful in molecular classification of cancer.

我们的目的是通过肿瘤中DNA或RNA水平的改变，通过全基因组扫描来鉴定参与多步胃肠道癌发生的肿瘤抑制基因。首先，应用代表性差异分析（RDA）以识别肿瘤细胞中纯合染色体区域的纯合染色体区域，这可能是假定的肿瘤抑制基因座。在胃癌细胞系OCUM-2MD3中，易于腹膜传播，三个染色体基因座，1p，3pl4和16q22被发现被纯度删除。假定的肿瘤抑制基因FHJT和WWOX分别位于3P和16Q缺失中，而从1P缺失中分离出一种新型的基因ZAP1，其异常转录本在各种癌细胞系中发现。其次，进行了DNA芯片分析以监测数千个基因的改变的表达谱。在2MD3细胞中，针对鳞状细胞谱系的基因被上调，而MHC II类基因在2MLN细胞系中被上调。在原发性胃癌中，已经鉴定出鉴定出癌症和非癌症的基因，或者已经鉴定出转移（+）和（ - ）。还获得了与肝肿瘤脱不同的基因，并用于对肝癌的分化等级进行分类。非参数统计分析，例如Kruskal-Wallis检验和非等级聚类，在癌症的分子分类中也非常有用。