Epithelial to mesenchymal transition (EMT) is a complex biological event, wherein polarized epithelial cells lose their integrity resulting in a mesenchymal phenotype with enhanced motility, a phenomenon known as metastasis. However, the underlying mechanisms of EMT are still poorly understood in cervical carcinomas. In this study, we investigated the molecular signalling events responsible for the effect of TGF-β, a potent inducer of EMT, on HeLa cervical cancer cells. We observed that TGF-β treatment (5 ng/mL) upregulates the expression of EMT-associated transcription factors such as Snail and Slug and downregulates the expression of epithelial markers such as ZO-1 and E-cadherin. Furthermore, treatment with TGF-β activates both Smad-dependent and Smad-independent signaling pathways, which subsides upon addition of Diphenyleneiodonium (DPI), a potent ROS inhibitor that inhibits NAPDH oxidase (NOX). TGF-β treatment enhanced cellular migration and invasion ability was diminished in the presence of ROS inhibitors. In addition, we also observed that ROS-mediated, TGF-β-induced EMT progression was inhibited using therapeutic candidates that target the key signal transduction mediators, including PI3K/AKT, ERK, and P38/MAPK. Accordingly, we demonstrated the involvement of redox biology (NOX2 and NOX4 mediate migration and invasion) in TGF-β-mediated EMT advancement and explored suitable therapeutic interventions.

中文翻译：

---

NAPDH氧化酶的作用及其在TGF-β介导的EMT进展中的治疗干预作用：HeLa宫颈癌细胞的体外分析

上皮到间充质转变（EMT）是一个复杂的生物学事件，其中极化的上皮细胞丧失完整性，导致具有增强运动性的间充质表型，这种现象被称为转移。然而，在宫颈癌中，EMT的潜在机制仍知之甚少。在这项研究中，我们研究了分子信号转导事件，该事件负责TGF-β（一种有效的EMT诱导剂）对HeLa宫颈癌细胞的作用。我们观察到TGF-β处理（5 ng / mL）上调了EMT相关转录因子Snail和Slug的表达，并下调了ZO-1和E-cadherin等上皮标志物的表达。此外，使用TGF-β进行治疗可激活Smad依赖性和Smad依赖性信号通路，这些信号通路在加入二苯并碘鎓（DPI）后消失，一种有效的ROS抑制剂，可抑制NAPDH氧化酶（NOX）。在ROS抑制剂的存在下，TGF-β治疗增强了细胞迁移，侵袭能力降低。此外，我们还观察到使用靶向PI3K / AKT，ERK和P38 / MAPK等关键信号转导介质的治疗性候选药物可抑制ROS介导的TGF-β诱导的EMT进展。因此，我们证明了氧化还原生物学（NOX2和NOX4介导迁移和入侵）参与TGF-β介导的EMT的发展，并探索了合适的治疗干预措施。使用靶向PI3K / AKT，ERK和P38 / MAPK等关键信号转导介质的治疗候选物，可以抑制TGF-β诱导的EMT进展。因此，我们证明了氧化还原生物学（NOX2和NOX4介导迁移和入侵）参与TGF-β介导的EMT的发展，并探索了合适的治疗干预措施。使用靶向PI3K / AKT，ERK和P38 / MAPK等关键信号转导介质的治疗候选物，可以抑制TGF-β诱导的EMT进展。因此，我们证明了氧化还原生物学（NOX2和NOX4介导迁移和入侵）参与TGF-β介导的EMT的发展，并探索了合适的治疗干预措施。