Hippo Y, Yashiro M, Ishii M, Taniguchi H, Tsutsumi S, Hirakawa K, Kodama T, Aburatani H
Genome Science Division, Research Center for Advanced Science and Technology, The University of Tokyo, Japan.
Cancer Res. 2001 Feb 1;61(3):889-95.
Scirrhous gastric cancer is often accompanied by metastasis to the peritoneum and/or lymph nodes, resulting in the highest mortality rate among gastric cancers. Mechanisms involved in gastric cancer metastasis are not fully clarified because metastasis involves multiple steps and requires the accumulation of altered expression of many different genes. Thus, independent analysis of any single gene would be insufficient to understand all of the aspects of gastric cancer metastasis. In this study, we performed global analysis on differential gene expression of a scirrhous gastric cancer cell line (OCUM-2M) and its derivative sublines with high potential for metastasis to the peritoneal cavity (OCUM-2MD3) and lymph nodes (OCUM-2MLN) in a nude mice model. By applying a high-density oligonucleotide array method, expression of approximately 6800 genes was analyzed, and selected genes were confirmed by the Northern blot method. In our observations in OCUM-2MD3 cells, 12 genes were up-regulated, and 20 genes were down-regulated. In OCUM-2MLN cells, five genes were up-regulated, and five genes were down-regulated. The analysis revealed two functional gene clusters with altered expression: (a) down-regulation of a cluster of squamous cell differentiation marker genes such as small proline-rich proteins [SPRRs (SPRR1A, SPRR1B, and SPRR2A], annexin A1, epithelial membrane protein 1, cellular retinoic acid-binding protein 2, and mesothelin in OCUM-2MD3 cells; and (b) up-regulation of a cluster of antigen-presenting genes such as MHC class II (DP, DR, and DM) and invariant chain (II) in OCUM-2MLN cells through up-regulation of CIITA (MHC class II transactivator). We then analyzed six gastric cancer cell lines by Northern blot and observed preferential up-regulation of trefoil factor 1, alpha-1-antitrypsin, and galectin 4 and down-regulation of cytidine deaminase in cells prone to peritoneal dissemination. Genes highly correlated with invasion or peritoneal dissemination of gastric cancer, such as E-cadherin or integrin beta4, were down-regulated in both of the derivative cell lines analyzed in this study. This is the first demonstration of global gene expression analysis of gastric cancer cells with different metastatic potentials, and these results provide a new insight in the study of human gastric cancer metastasis.
硬癌性胃癌常伴有腹膜和/或淋巴结转移，导致其成为胃癌中死亡率最高的类型。胃癌转移所涉及的机制尚未完全阐明，因为转移涉及多个步骤，且需要多种不同基因的表达改变不断积累。因此，仅对任何单个基因进行独立分析，不足以全面了解胃癌转移的所有方面。在本研究中，我们在裸鼠模型中，对一种硬癌性胃癌细胞系（OCUM-2M）及其向腹腔（OCUM-2MD3）和淋巴结（OCUM-2MLN）转移潜力高的衍生亚系进行了基因表达差异的全局分析。通过应用高密度寡核苷酸阵列方法，分析了约6800个基因的表达情况，并通过Northern印迹法对所选基因进行了验证。在我们对OCUM-2MD3细胞的观察中，有12个基因上调，20个基因下调。在OCUM-2MLN细胞中，有5个基因上调，5个基因下调。分析揭示了两个表达改变的功能基因簇：（a）在OCUM-2MD3细胞中，一组鳞状细胞分化标志物基因下调，如富含脯氨酸的小分子蛋白[SPRRs（SPRR1A、SPRR1B和SPRR2A）]、膜联蛋白A1、上皮膜蛋白1、细胞视黄酸结合蛋白2和间皮素；（b）在OCUM-2MLN细胞中，通过上调CIITA（MHC II类反式激活因子），一组抗原呈递基因上调，如MHC II类分子（DP、DR和DM）和恒定链（II）。然后，我们通过Northern印迹法分析了6个胃癌细胞系，观察到三叶因子1、α1-抗胰蛋白酶和半乳糖凝集素4在易于腹膜播散的细胞中优先上调，而胞苷脱氨酶下调。在本研究分析的两个衍生细胞系中，与胃癌侵袭或腹膜播散高度相关的基因，如E-钙黏蛋白或整合素β4，均下调。这是首次对具有不同转移潜能的胃癌细胞进行全局基因表达分析，这些结果为人类胃癌转移的研究提供了新的见解。
