Yamanaka Masanori, Kimura Fumihiro, Kagata Yutaka, Kondoh Nobuo, Asano Tomohiko, Yamamoto Mikio, Hayakawa Masamichi
Department of Urology, National Defense Medical College, Saitama 359-8513, Japan.
Oncol Rep. 2008 Apr;19(4):865-74.
To identify new target marker genes in renal cell carcinoma (RCC), we compared the gene expression profiles of clear cell RCC (cc-RCC) and normal kidney tissue using serial analysis of gene expression. Our results revealed that the transforming growth factor beta induced 68 kDa protein (TGF-betaI: beta ig-h3 (BIGH3), plasminogen activator inhibitor-1 (PAI-1) and transforming growth factor beta1 (TGF-beta1) genes are up-regulated in cc-RCC. To further assess the role of BIGH3 in RCC, we investigated the mRNA expression levels of BIGH3, TGFbeta1, PAI-1 and also of TGF-beta1 related genes in 53 RCC and 30 normal kidney tissues by quantitative real-time RT-PCR (QRT-PCR). We further determined the BIGH3 protein levels in 52 cc-RCC paraffin-embedded tissue samples by immunohistochemistry. BIGH3 mRNA was found to be highly overexpressed in cc-RCC compared with normal tissues with an average ratio of 27. The mRNA levels of TGF-beta1 and PAI-1 were also detected at significantly elevated levels in these cancers. Immunohistochemical analysis of BIGH3 also revealed strong staining in the majority of the cc-RCC samples. In addition, the up-regulation of BIGH3 and PAI-1 was found to correlate with the clinicopathological parameters associated with a poorer patient outcome, whereas TGF-beta1 expression was determined to be unrelated to cancer progression. Strong BIGH3 staining thus tended to be associated with a poor prognosis. BIGH3 was also induced in some RCC cell lines by TGF-beta1 stimulation and this correlated well with PAI-1 up-regulation, suggesting that these enhancements are regulated by a similar mechanism in these tumors.
为了鉴定肾细胞癌(RCC)中的新靶标标记基因,我们使用基因表达序列分析比较了透明细胞RCC(cc-RCC)和正常肾组织的基因表达谱。我们的结果显示,转化生长因子β诱导的68 kDa蛋白(TGF-βI:βig-h3(BIGH3)、纤溶酶原激活物抑制剂-1(PAI-1)和转化生长因子β1(TGF-β1)基因在cc-RCC中上调。为了进一步评估BIGH3在RCC中的作用,我们通过定量实时RT-PCR(QRT-PCR)研究了53例RCC和30例正常肾组织中BIGH3、TGFβ1、PAI-1以及TGF-β1相关基因的mRNA表达水平。我们还通过免疫组织化学测定了52例cc-RCC石蜡包埋组织样本中的BIGH3蛋白水平。与正常组织相比,发现cc-RCC中BIGH3 mRNA高度过表达,平均比值为27。在这些癌症中也检测到TGF-β1和PAI-1的mRNA水平显著升高。BIGH3的免疫组织化学分析还显示,大多数cc-RCC样本中有强染色。此外,发现BIGH3和PAI-1的上调与患者预后较差相关的临床病理参数相关,而TGF-β1表达与癌症进展无关。因此,强BIGH3染色往往与预后不良相关。TGF-β1刺激也在一些RCC细胞系中诱导了BIGH3,这与PAI-1上调密切相关,表明这些增强在这些肿瘤中受类似机制调控。