British Journal of Cancer, 2013, 108(10):2070-2078.

Genistein downregulates onco-miR-1260b and inhibits Wnt-signalling in renal cancer cells

H Hirata, K Ueno, K Nakajima, et al

Department of Urology, San Francisco Veterans Affairs Medical Center and University of California at San Francisco, San Francisco, CA 94121, USA; et al

BACKGROUND:

Wnt-signalling has an important role in renal cancer and it is modulated by genistein in other cancers. Recently, microRNAs (miRNAs) have emerged as new regulators of gene expression. Thus, we focused on miRNAs to examine the regulatory mechanism of genistein on the Wnt-signalling pathway in renal cell carcinoma (RCC).

METHODS:

Initially, we investigated the effect of genistein on Wnt-signalling (TOPflash reporter assay (TCF reporter assays)) in renal cancer cells, and using microarray identified candidate miRNAs whose expression was decreased by genistein. We performed functional analyses and investigated the relationship between miRNA expression and renal cancer patient outcomes. We also did 3'UTR luciferase assays to look at direct miRNA regulation of Wnt-signalling-related genes.

RESULTS:

Genistein promoted apoptosis while inhibiting RCC cell proliferation and invasion. Genistein also decreased TCF reporter activity in RCC cells. We found that miR-1260b was highly expressed and significantly downregulated by genistein in RCC cells. The expression of miR-1260b was significantly higher in renal cancer tissues compared with normal, and significantly related to overall shorter survival. In addition, miR-1260b promoted renal cancer cell proliferation and invasion in RCC cells. The 3'UTR luciferase activity of target genes (sFRP1, Dkk2, Smad4) was significantly decreased and their protein expression significantly upregulated in miR-1260b inhibitor-transfected renal cancer cells.

CONCLUSION:

Our data suggest that genistein inhibited Wnt-signalling by regulating miR-1260b expression in renal cancer cells.

英国《英国癌症杂志》，2013年5月

在肾癌细胞中金雀异黄素下调onco-miR-1260b 并抑制 Wnt 信号

平田H，上野 K，中岛K，等

美国加利福尼亚大学旧金山分校和旧金山退伍军人事务医学中心泌尿外科等

背景︰

Wnt 信号在肾癌中具有重要的作用，并且在其他癌症中由金雀异黄素调节。最近，小分子 RNA(miRNA) 已成为基因表达的新型调节因子。因此，我们专注于miRNAs来 研究在肾细胞癌 (RCC)中金雀异黄素对Wnt 信号通路的调节机制。

方法︰

最初，在肾癌细胞中，我们研究了金雀异黄素的影响对 Wnt 信号 （TOPflash 记录测定 （TCF 记录实验法）），并且使用基因芯片确定了由金雀异黄素降低表达的候选miRNA。我们进行了功能分析并研究了 miRNA 表达与肾癌患者治疗效果之间的关系。我们还做了 3' UTR 荧光素酶检测来观察miRNA对Wnt 信号相关基因的直接调控。

结果︰

金雀异黄素促进细胞凋亡并抑制RCC细胞增殖和侵袭。在RCC细胞中金雀异黄素也会降低TCF记录活性。我们发现在RCC细胞中miR-1260b 被金雀异黄素高度表达和明显下调。肾肿瘤组织的miR-1260b 的表达明显高于正常组织，与对总体缩短的生存率明显相关。此外，在RCC细胞中miR-1260b 促进了肾癌细胞的增殖和侵袭。靶向基因(sFRP1，Dkk2，Smad4)的3' UTR 荧光素酶基因的活性明显降低，并且它们的蛋白表达在miR-1260b 抑制因子-基因转染的肾癌细胞中明显上调。

结论︰

我们的数据表明，金雀异黄素通过调节 miR-1260b 在肾癌细胞中的表达来抑制 Wnt 信号。