Laboratory of Clinical Virology, Medical School, University of Crete, Heraklion, 71110 Crete, Greece.
Pathol Oncol Res. 2011 Jun;17(2):181-90. doi: 10.1007/s12253-010-9295-1. Epub 2010 Sep 18.
RKIP has been shown to regulate the RAS-RAF-MEK-ERK kinase cascade acting as modulator of apoptosis and metastasis in prostate cancer. Our goal was to examine the expression of the RAF (A-RAF, B-RAF and RAF-1) and RKIP genes in urinary bladder cancer. Microarray analysis and qPCR was employed to investigate the expression of RAF and RKIP, in 30 patients with transitional cell carcinoma (TCC) of the urinary bladder vs. the corresponding levels of adjacent normal tissue. Computational analysis was also performed on Gene Expression Omnibus (GEO) datasets, to unravel differences in the expression of RAF or RKIP between tumor and control samples, and between superficial and muscle invasive tumors. Microarray analysis revealed >2-fold expression of BRAF and RKIP in T2, T3, grade III tumors vs. controls. B-RAF over-expression was verified by qPCR in pT1, grade III tumors vs. their normal counterparts (p = 0.016). qPCR revealed a significant RKIP reduction in TCC vs. normal tissue (p = 0.002 and p < 0.001 for T1, grade II and Ta-T1, grade III, respectively); All RAF genes were positively correlated among each other (A-RAF/B-RAF, p = 0.003; A-RAF/RAF-1, p < 0.001; B-RAF/RAF-1, p = 0.050), whereas B-RAF was negatively correlated with RKIP in TCC (p = 0.050). Further computational analysis revealed different expression profiles for the genes of interest, among muscle invasive carcinomas, superficial TCCs, cystectomy specimens and normal tissue. The reduced RKIP mRNA levels in TCC and the elevated levels of B-RAF in pT1, grade III tumors vs. normal tissue, corroborate that these genes are involved in the pathogenesis of urinary bladder cancer.
RKIP 已被证明可调节 RAS-RAF-MEK-ERK 激酶级联，作为前列腺癌凋亡和转移的调节剂。我们的目标是研究 RAF（A-RAF、B-RAF 和 RAF-1）和 RKIP 基因在膀胱癌中的表达。采用微阵列分析和 qPCR 方法，检测 30 例膀胱癌患者肿瘤组织与配对正常组织中 RAF 和 RKIP 的表达情况。还对基因表达综合数据库（GEO）数据集进行了计算分析，以揭示肿瘤和对照样本、表浅肿瘤和肌层浸润性肿瘤之间 RAF 或 RKIP 表达的差异。微阵列分析显示，BRAF 和 RKIP 在 T2、T3、G3 肿瘤中的表达高于对照。qPCR 验证了 pT1、G3 肿瘤中 B-RAF 的过表达（p = 0.016）。qPCR 显示 TCC 与正常组织相比 RKIP 显著减少（T1、G2 和 Ta-T1、G3 分别为 p = 0.002 和 p < 0.001）；所有 RAF 基因彼此之间呈正相关（A-RAF/B-RAF，p = 0.003；A-RAF/RAF-1，p < 0.001；B-RAF/RAF-1，p = 0.050），而 B-RAF 在 TCC 中与 RKIP 呈负相关（p = 0.050）。进一步的计算分析显示，在肌层浸润性膀胱癌、表浅膀胱癌、膀胱切除术标本和正常组织中，这些基因的表达谱不同。TCC 中 RKIP mRNA 水平降低，pT1、G3 肿瘤中 B-RAF 水平升高，与这些基因参与膀胱癌的发病机制相符。
