British Journal of Cancer, 2014, 110(6):1645-54.

Genistein downregulates onco-miR-1260b and upregulates sFRP1 and Smad4 via demethylation and histone modification in prostate cancer cells

H Hirata, Y Hinoda, et al

Department of Urology, San Francisco Veterans Affairs Medical Center and University of California at San Francisco, San Francisco, California, USA; Department of Oncology and Laboratory Medicine, Yamaguchi University Graduate School of Medicine, Yamaguchi, Japan; Department of Pathology, San Francisco Veterans Affairs Medical Center and University of California at San Francisco, San Francisco, California, USA

BACKGROUND:

Recently several microRNAs (miRNAs) have been found to be regulated by genistein in cancer cells. In this study, we focused on the gene regulatory effect of genistein on microRNA and its target genes in prostate cancer (PC).

METHODS:

Initially, we investigated the effect of genistein on prostate cancer cells and identified that the expression of miRNA-1260b was decreased by genistein. We performed functional analyses and investigated the relationship between miRNA-1260b expression and prostate cancer patient outcomes. Two target genes (sFRP1 and Smad4) of miR-1260b were identified based on computer algorithm and 3'UTR luciferase assay was carried out to determine direct miRNA regulation of the genes.

RESULTS:

Genistein promoted apoptosis while inhibiting prostate cancer cell proliferation, invasion and TCF reporter activity in PC cells. MiR-1260b was highly expressed in prostate cancer tissues and significantly downregulated by genistein in PC cells. After knocking down miR-1260b, cell proliferation, invasion, migration and TCF reporter activity were decreased in PC cells. Western analysis and 3'UTR luciferase assay showed that the two target genes (sFRP1 and Smad4) were directly regulated by miR-1260b. The expression of sFRP1 and Smad4 was significantly decreased in prostate cancer tissues. Genistein also increased expression of these two genes via DNA demethylation and histone modifications.

CONCLUSIONS:

Our data suggest that genistein exerts its anti-tumour effect via downregulation of miR-1260b that targeted sRRP1 and Smad4 genes in prostate cancer cells. The expression of sFRP1 and Smad4 was also modulated by genistein via DNA methylation or histone modifications in PC cell lines.

英国《英国癌症杂志》，2014年3月

在前列腺癌细胞中金雀异黄素通过去甲基化和组蛋白修饰来下调 onco-miR-1260b 并上调 sFRP1 和 Smad4

平田H，日野田 Y，等

美国加利福尼亚旧金山退伍军人事务医学中心泌尿外科和加利福尼亚大学；日本山口大学医学研究院肿瘤和实验室药品系；美国加利福尼亚旧金山退伍军人事务医学中心病理学系和加利福尼亚大学

背景︰

最近几种小分子 RNA (miRNAs) 被发现在肿瘤细胞中受金雀异黄素调节。在此研究中，我们关注金雀异黄素对前列腺癌 (PC) miRNA的基因调节作用及其靶向基因。

方法︰

最初，我们探究了金雀异黄素对前列腺癌细胞的影响并确认了 miRNA-1260b 的表达被金雀异黄素下调。我们进行了功能分析并探究了 miRNA-1260b 表达与前列腺癌患者疗效之间的关系。miRNA-1260b的两种靶向基因 （sFRP1 和 Smad4）基于计算机算法被确认，并进行了 3' UTR 荧光素酶检测以确认基因的直接 miRNA调节。

结果︰

金雀异黄素抑制前列腺癌细胞增殖、 侵袭和 TCF 细胞活性的同时促进细胞凋亡。在前列腺癌组织中MIR-1260b被高度表达，并且被金雀异黄素显著下调。在 PC 细胞中，在中断miR-1260b之后， 细胞增殖、 侵袭、 迁移和 TCF 活性被降低。免疫印迹分析和 3' UTR 荧光素酶检测表明两种靶向基因 （sFRP1 和 Smad4）直接被miR-1260b调控。在前列腺癌组织中，SFRP1 和 Smad4 的表达被明显降低。金雀异黄素也通过 DNA 去甲基化和组蛋白修饰增加了这两种基因的表达。

结论︰

我们的数据表明，在前列腺癌细胞中金雀异黄素以 sRRP1 和 Smad4 基因为靶向通过下调 miR-1260b 发挥其抗肿瘤活性。在 PC细胞中，SFRP1 和 Smad4的 表达也被金雀异黄素通过 DNA 甲基化或组蛋白修饰调节。