Cisplatin (DDP) is a widely used chemotherapy drug for advanced cervical cancer (CC), but resistance poses a significant challenge. While miR-4739 has been implicated in tumor development, its specific role in regulating DDP resistance in CC remains unclear. We analyzed the expression levels of miR-4739 and RHBDD2 in DDP-resistant and DDP-sensitive CC tissues using quantitative real-time polymerase chain reaction (PCR) and assessed their correlation through Spearman’s correlation analysis. DDP-resistant CC cell lines (HeLa/DDP and SiHa/DDP) were established by gradually increasing DDP concentrations, followed by transfection with miR-4739 mimics, si-RHBDD2, or a RHBDD2 overexpression vector. A series of functional assays, including CCK-8 assay, colony formation, flow cytometry, and transwell assay were performed. The interaction between miR-4739 and RHBDD2 was confirmed by luciferase reporter assay. We examined the protein levels of RHBDD2, P-gP, MRP1, cleaved caspase-3, and E-cadherin through western blot analysis. Moreover, we generated xenograft tumors by injecting stably transfected HeLa/DDP cells into mice to compare their tumorigenesis capacity. We observed downregulation of miR-4739 and upregulation of RHBDD2 in DDP-resistant CC tissues and cell lines. MiR-4739 was shown to directly bind to RHBDD2 gene sequences to repress RHBDD2 expression in HeLa/DDP and SiHa/DDP cells. Our in vitro and in vivo experiments demonstrated that overexpressing miR-4739 overcame DDP resistance in CC cells by targeting RHBDD2. Furthermore, RHBDD2 overexpression reversed the effects of miR-4739 mimics on drug-resistance-related proteins (P-gP and MRP1) and the expression of cleaved caspase-3 and E-cadherin in HeLa/DDP cells. In summary, our study revealed that miR-4739 can reverse DDP resistance by modulating RHBDD2 in CC cells.

中文翻译：

---

microRNA-4739通过负调控RHBDD2增强人宫颈癌细胞顺铂化疗敏感性的作用

顺铂（DDP）是一种广泛用于治疗晚期宫颈癌（CC）的化疗药物，但耐药性带来了重大挑战。虽然 miR-4739 与肿瘤发展有关，但其在调节 CC 中 DDP 耐药性中的具体作用仍不清楚。我们使用定量实时聚合酶链反应（PCR）分析了 DDP 耐药和 DDP 敏感 CC 组织中 miR-4739 和 RHBDD2 的表达水平，并通过 Spearman 相关分析评估了它们的相关性。通过逐渐增加 DDP 浓度，然后用 miR-4739 模拟物、si-RHBDD2 或 RHBDD2 过表达载体转染来建立 DDP 抗性 CC 细胞系（HeLa/DDP 和 SiHa/DDP）。进行了一系列功能测定，包括CCK-8测定、集落形成、流式细胞术和transwell测定。通过荧光素酶报告基因测定证实了 miR-4739 和 RHBDD2 之间的相互作用。我们通过蛋白质印迹分析检查了 RHBDD2、P-gP、MRP1、cleaved caspase-3 和 E-cadherin 的蛋白水平。此外，我们通过将稳定转染的HeLa/DDP细胞注射到小鼠体内来产生异种移植肿瘤，以比较它们的致瘤能力。我们在 DDP 抗性 CC 组织和细胞系中观察到 miR-4739 下调和 RHBDD2 上调。MiR-4739 显示可直接结合 RHBDD2 基因序列，抑制 HeLa/DDP 和 SiHa/DDP 细胞中的 RHBDD2 表达。我们的体外和体内实验表明，过表达 miR-4739 通过靶向 RHBDD2 克服了 CC 细胞中的 DDP 耐药性。此外，RHBDD2 过表达逆转了 miR-4739 模拟物对 HeLa/DDP 细胞中耐药相关蛋白（P-gP 和 MRP1）以及 caspase-3 和 E-cadherin 表达的影响。总之，我们的研究表明，miR-4739 可以通过调节 CC 细胞中的 RHBDD2 来逆转 DDP 耐药性。