The underlying mechanisms of recurrence and metastasis of epithelial ovarian cancer (EOC) are largely unknown. In the present study, we investigated the clinical significance of microRNA-125b (miR-125b) and its role in ovarian tumorigenesis and progression. Seventy patients of EOC and paired tissues were enrolled from 2015 to 2017. qRT-PCR was used to evaluate miR-125b expression in tumor tissues and EOC cell line. Gain-and-loss function of miR-125b was achieved to explore the changes in cell biological function. We found that miR-125b expression in EOC tissues, especially in the high-grade tissues (P < 0.001), was significantly lower compared to the matched adjacent noncancerous tissues and associated with pathological type, stage, and overall survival (P < 0.05). Upregulation of miR-125b promoted apoptosis and decreased cell survival rate and migration, and vice versa in vitro. Mechanistically, miR-125b negatively regulated S100A4, a metastasis-associated protein. MiR-125b overexpression significantly decreased tumor growth and inhibited lung metastasis in vivo. Our results supported that miR-125b contributes to the progression of EOC by targeting S100A4. It potentially acts as a potential biomarker and therapeutic target of EOC.

上皮性卵巢癌（EOC）复发和转移的潜在机制在很大程度上是未知的。在本研究中，我们调查了 microRNA-125b (miR-125b) 的临床意义及其在卵巢肿瘤发生和进展中的作用。2015-2017 年共纳入 70 例 EOC 和配对组织患者。 qRT-PCR 用于评估 miR-125b 在肿瘤组织和 EOC 细胞系中的表达。实现了 miR-125b 的增益和损失功能，以探索细胞生物学功能的变化。我们发现 miR-125b 在 EOC 组织中的表达，尤其是在高级别组织中（P < 0.001），与匹配的相邻非癌组织相比显着降低，并与病理类型、分期和总生存期相关（P < 0.05） .体外。从机制上讲，miR-125b 负向调节 S100A4，一种转移相关蛋白。MiR-125b 过表达显着降低了肿瘤生长并抑制了体内肺转移。我们的结果支持 miR-125b 通过靶向 S100A4 促进 EOC 的进展。它有可能作为 EOC 的潜在生物标志物和治疗靶点。