Oji Y, Ogawa H, Tamaki H, Oka Y, Tsuboi A, Kim E H, Soma T, Tatekawa T, Kawakami M, Asada M, Kishimoto T, Sugiyama H
Department of Clinical Laboratory Science, Osaka University Medical School.
Jpn J Cancer Res. 1999 Feb;90(2):194-204. doi: 10.1111/j.1349-7006.1999.tb00733.x.
To determine the role of the Wilms' tumor gene WT1 in tumorigenesis of solid tumors, expression of the WT1 gene was examined in 34 solid tumor cell lines (four gastric cancer cell lines, five colon cancer cell lines, 15 lung cancer cell lines, four breast cancer cell lines, one germ cell tumor cell line, two ovarian cancer cell lines, one uterine cancer cell line, one thyroid cancer cell line, and one hepatocellular carcinoma cell line) by means of quantitative reverse transcriptase-polymerase chain reaction. WT1 gene expression was detected in three of the four gastric cancer cell lines, all of the five colon cancer cell lines, 12 of the 15 lung cancer cell lines, two of the four breast cancer cell lines, the germ cell tumor cell line, the two ovarian cancer cell lines, the uterine cancer cell line, the thyroid cancer cell line, and the hepatocellular carcinoma cell line. Therefore, of the 34 solid tumor cell lines examined, 28 (82%) expressed WT1. Three cell lines expressing WT1 (gastric cancer cell line AZ-521, lung cancer cell line OS3, and ovarian cancer cell line TYK-nu) were further analyzed for mutations and/or deletions in the WT1 gene by means of single-strand conformation polymorphism analysis. However, no mutations or deletions were detected in the region of the WT1 gene ranging from the 3' end of exon 1 to exon 10 (the WT1 gene consists of 10 exons) in these three cell lines. Furthermore, when AZ-521, OS3, and TYK-nu cells were treated with WT1 antisense oligomers, the growth of these cells was significantly inhibited in association with a reduction in WT1 protein levels. Furthermore, constitute expression of the transfected WT1 gene in cancer cells inhibited the antisense effect of WT1 antisense oligomer on cell growth. These results indicated that the WT1 gene plays an essential role in the growth of solid tumors and performs an oncogenic rather than a tumor-suppressor gene function.
为了确定威尔姆斯瘤基因WT1在实体瘤发生中的作用，通过定量逆转录聚合酶链反应检测了34种实体瘤细胞系（4种胃癌细胞系、5种结肠癌细胞系、15种肺癌细胞系、4种乳腺癌细胞系、1种生殖细胞瘤细胞系、2种卵巢癌细胞系、1种子宫癌细胞系、1种甲状腺癌细胞系和1种肝癌细胞系）中WT1基因的表达。在4种胃癌细胞系中的3种、5种结肠癌细胞系中的所有细胞系、15种肺癌细胞系中的12种、4种乳腺癌细胞系中的2种、生殖细胞瘤细胞系、2种卵巢癌细胞系、子宫癌细胞系、甲状腺癌细胞系和肝癌细胞系中检测到WT1基因表达。因此，在所检测的34种实体瘤细胞系中，28种（82%）表达WT1。对3种表达WT1的细胞系（胃癌细胞系AZ - 521、肺癌细胞系OS3和卵巢癌细胞系TYK - nu）通过单链构象多态性分析进一步检测WT1基因的突变和/或缺失情况。然而，在这3种细胞系中，未检测到WT1基因从外显子1的3'末端到外显子10（WT1基因由10个外显子组成）区域的突变或缺失。此外，当用WT1反义寡核苷酸处理AZ - 521、OS3和TYK - nu细胞时，这些细胞的生长明显受到抑制，同时WT1蛋白水平降低。此外，在癌细胞中转染的WT1基因的组成性表达抑制了WT1反义寡核苷酸对细胞生长的反义作用。这些结果表明，WT1基因在实体瘤生长中起重要作用，发挥致癌基因而非抑癌基因的功能。
