miR-135b通过靶向FOXO1促进子宫内膜癌细胞的增殖

目的探讨miR-135b在子宫内膜癌中的表达及对子宫内膜癌细胞增殖的作用的机制。方法运用RT-PCR的方法检测22 对子宫内膜癌组织及相应的癌旁组织中的miR-135b 和FOXO1 的表达；运用RT-PCR 的方法检测JEC、Ishikawa、HEC-1-B、 RL-952这4种子宫内膜癌细胞株中miR-135b和FOXO1的表达。分别转染miR-135b的模拟物抑制物于子宫内膜癌细胞株，通 过RT-PCR检测转染的效果，通过MTT增殖试验检测对子宫内膜癌细胞增殖的影响。通过RT-PCR的方法检测FOXO1 mRNA 的变化，Western blotting 检测在FOXO1 蛋白的变化。结果miR-135b 在子宫内膜癌组织中较对应的癌旁组织表达增高（P< 0.05）, FOXO1在子宫内膜癌组织中较对应的癌旁组织表达降低（P<0.05）。荧光定量PCR显示子宫内膜癌细胞中miR-135b与 FOXO1表达趋势成负相关。miR-135b能促进子宫内膜癌细胞增殖（P<0.05）。上调miR-135b能够降低FOXO1 mRNA和蛋白 的表达（P<0.05），下调miR-135b能够提高FOXO1 mRNA和蛋白的表达（P<0.05）。结论miR-135b在子宫内膜癌的发生发展 中发挥重要的作用，其部分分子机制可能是通过调控靶基因FOXO1而发挥作用。

MiR-135b promotes proliferation of endometrial carcinoma cells by targeting FOXO1

Objective To explore the expression of miR-135b in endometrial carcinoma and the mechanism by which miR-135b promotes the proliferation of endometrial cancer cells. Methods The expressions of miR-135b and FOXO1 were using RT-PCR detected in 22 fresh endometrial cancer tissues and paired adjacent tissues and also in endometrial cancer cell lines JEC, Ishikawa, HEC-1-B, and RL-952. The RL-952 and Ishikawa cell lines were transfected with miR-135b mimics or inhibitors, and the changes in their proliferative activity were detected with MTT assay;the expressions of FOXO1 mRNA and protein were detected by RT-PCR and Western blotting, respectively. Results The expression of miRNA135b was significantly up-regulated and FOXO1 expression was down-regulated in endometrial carcinoma tissues as compared with the adjacent tissues (P<0.05). The mRNA expression of miR-135b was negatively correlated with the expression of FOXO1 in endometrial carcinoma. In RL-952 and Ishikawa cell lines, transfection with miR-135b mimics obviously promoted the cell proliferation (P<0.05). Up-regulation of miR-135b significantly decreased the expressions of FOXO1 protein and mRNA (P<0.05), and down-regulation of miR-135b increased FOXO1 expressions (P<0.05). Conclusions MiR-135b plays an important role in the occurrence and development of endometrial carcinoma partially by regulating its target gene FOXO1.