Human umbilical cord mesenchymal stem cells can be obtained from different parts of the umbilical cord, including Wharton's jelly. Transplantation of Wharton's jelly umbilical cord stem cells (WJCMSCs) is a promising strategy for the treatment of various diseases. However, the molecular mechanisms underlying the proliferation of WJCMSCs are incompletely understood. Here, we report that overexpression of miR‐196b‐5p in WJCMSCs suppresses proliferation and arrests the cell cycle in G0/G1 phase, whereas knockdown of miR‐196b‐5p promotes WJCMSC proliferation and cell‐cycle progression. Moreover, miR‐196b‐5p overexpression resulted in decreased levels of Cyclin A, Cyclin D, Cyclin E and cyclin‐dependent kinases 2 and increased levels of p15^INK4b, whereas miR‐196b‐5p knockdown had the opposite effects. In conclusion, our data suggests that miR‐196b‐5p inhibits WJCMSC proliferation by enhancing G0/G1‐phase arrest.

中文翻译：

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miR-196b-5p抑制沃顿氏胶脐带干细胞增殖

人脐带间充质干细胞可以从脐带的不同部位获得，包括沃顿氏胶。沃顿氏胶脐带干细胞（WJCMSCs）的移植是治疗各种疾病的一种有前途的策略。然而，WJCMSCs 增殖的分子机制尚不完全清楚。在这里，我们报告了 WJCMSCs 中 miR-196b-5p 的过表达抑制增殖并将细胞周期阻滞在 G0/G1 期，而 miR-196b-5p 的敲低促进 WJCMSC 增殖和细胞周期进程。此外，miR-196b-5p 过表达导致细胞周期蛋白 A、细胞周期蛋白 D、细胞周期蛋白 E 和细胞周期蛋白依赖性激酶 2 水平降低，p15 ^{INK4b水平升高}，而 miR-196b-5p 敲低具有相反的效果。总之，我们的数据表明 miR-196b-5p 通过增强 G0/G1 期阻滞来抑制 WJCMSC 增殖。