Department of Obstetrics and Gynecology Harbor-University of California Los Angeles Medical Center and Los Angeles Biomedical Research Institute, Torrance, California.
Department of Obstetrics and Gynecology Harbor-University of California Los Angeles Medical Center and Los Angeles Biomedical Research Institute, Torrance, California.
Fertil Steril. 2019 Dec;112(6):1180-1189. doi: 10.1016/j.fertnstert.2019.07.1324.
To determine the expression of miR-29c and its target gene transforming growth factor-β3 (TGF-β3) in leiomyoma and the mechanisms of their reciprocal regulation.
Experimental study.
Academic research laboratory.
PATIENT(S): Women undergoing hysterectomy for leiomyoma.
INTERVENTION(S): Overexpression and underexpression of miR-29c; blockade of DNA methyltransferase 1 (DNMT1).
MAIN OUTCOME MEASURE(S): The miR-29c and its target gene TGF-β3 in leiomyoma and the effects of TGF-β3 and blockade of DNMT1 on miR-29c expression.
RESULT(S): Leiomyoma expressed significantly lower levels of miR-29c, but higher expression of TGF-β3 compared with matched myometrium. The expression of TGF-β3 and miR-29c were independent of race/ethnicity. Using 3' untranslated region luciferase reporter assay we confirmed that TGF-β3 is a direct target of miR-29c in leiomyoma smooth muscle cells (LSMCs). Gain-of-function of miR-29c in LSMCs inhibited the expression of TGF-β3 at protein and messenger RNA levels, whereas loss-of-function of miR-29c had the opposite effect. Treatment of LSMCs with TGF-β3 inhibited the expression of miR-29c, whereas it stimulated DNMT1 expression. Knockdown of DNMT1 through transfection with small interfering RNA significantly decreased the expression of TGF-β3, and induced miR-29c expression. Knockdown of DNMT1 also attenuated the inhibitory effect of TGF-β3 on miR-29c expression. Furthermore, we demonstrated that TGF-β3 increased the methylation level of miR-29c promoter in LSMCs.
CONCLUSION(S): There is an inverse relationship in the expression of TGF-β3 and miR-29c in leiomyoma. The TGF-β3 is a direct target of miR-29c and inhibits the expression of miR-29c through an epigenetic mechanism. The cross-talk between miR-29c and TGF-β3 provides a feed forward mechanism of fibrosis in leiomyoma.
确定 miR-29c 及其靶基因转化生长因子-β3（TGF-β3）在子宫肌瘤中的表达及其相互调节的机制。
实验研究。
学术研究实验室。
因子宫肌瘤而行子宫切除术的女性。
miR-29c 的过表达和低表达；DNA 甲基转移酶 1（DNMT1）的阻断。
子宫肌瘤中 miR-29c 及其靶基因 TGF-β3 的表达情况，以及 TGF-β3 和阻断 DNMT1 对 miR-29c 表达的影响。
与配对的子宫肌层相比，子宫肌瘤中 miR-29c 的表达明显降低，但 TGF-β3 的表达升高。TGF-β3 和 miR-29c 的表达与种族/民族无关。通过 3'非翻译区荧光素酶报告基因检测，我们证实 TGF-β3 是子宫肌瘤平滑肌细胞（LSMCs）中 miR-29c 的直接靶基因。在 LSMCs 中过表达 miR-29c 可抑制 TGF-β3 蛋白和信使 RNA 水平的表达，而低表达 miR-29c 则有相反的作用。TGF-β3 处理 LSMCs 可抑制 miR-29c 的表达，而刺激 DNMT1 的表达。通过转染小干扰 RNA 敲低 DNMT1 可显著降低 TGF-β3 的表达，并诱导 miR-29c 的表达。DNMT1 的敲低也减弱了 TGF-β3 对 miR-29c 表达的抑制作用。此外，我们证实 TGF-β3 可增加 LSMCs 中 miR-29c 启动子的甲基化水平。
子宫肌瘤中 TGF-β3 和 miR-29c 的表达呈负相关。TGF-β3 是 miR-29c 的直接靶基因，通过表观遗传机制抑制 miR-29c 的表达。miR-29c 和 TGF-β3 之间的相互作用为子宫肌瘤纤维化提供了一个正反馈机制。
