MicroRNA-139-5p affects cisplatin sensitivity in human nasopharyngeal carcinoma cells by regulating the epithelial-to-mesenchymal transition.

Nasopharyngeal carcinoma (NPC) is a head and neck cancer associated with poor prognosis. Many studies have shown that the epithelial-to-mesenchymal transition (EMT) is important in cancer progression, metastasis, and chemotherapy resistance and that microRNAs (miRNAs) play a key role in chemotherapy resistance associated with EMT. The miRNA miR-139-5p is downregulated in many human cancers and is closely related to tumor progression. The aim of this study was to investigate the ability of miR-139-5p to influence the cisplatin resistance, apoptosis, invasion and migration in NPC cells through the regulation of the EMT. We investigated these processes in parental HNE1 and cisplatin-resistant HNE1/DDP cells transfected with miR-139-5p inhibitors and mimics, respectively. Our results suggest that the upregulation of miR-139-5p expression inhibits proliferation, invasion, migration and EMT in human NPC cells. In addition, we found that miR-139-5p expression levels and DDP-induced apoptosis positively correlate in NPC cells. In conclusion, our results demonstrate that miR-139-5p can regulate the migration, invasion and DDP resistance in human NPC by modulating the EMT. The regulation of miR-139-5p levels might be a new approach to reverse EMT and DDP resistance and counteract metastasis and chemotherapy resistance in human NPC.

Shao Q ，Zhang P ，Ma Y ，Lu Z ，Meng J ，Li H ，Wang X ，Chen D ，Zhang M ，Han Y ，Liu H ，Ma S ... -  《-》

miR-205-5p regulates epithelial-mesenchymal transition by targeting PTEN via PI3K/AKT signaling pathway in cisplatin-resistant nasopharyngeal carcinoma cells.

Epithelial-mesenchymal transition (EMT) symbolizes the predominant program of advanced-stage cancer, it is critical in cancer progression, metastasis, and chemotherapy resistance. In this study, the metastatic properties of nasopharyngeal carcinoma (NPC) cells were evaluated by morphological examination, wound healing assay, migration and invasion assay. Western blotting and qRT-PCR were used to ascertain the expression of markers which were associated with EMT. The effects of miR-205-5p on invasion, migration, EMT and proliferation of NPC cells were evaluated and the molecular mechanisms of their interaction were explored. In this study, we manifested firstly that the expression of miR-205-5p in cisplatin-resistant NPC cell line HNE1/DDP was obviously up-regulated than that in its parental cell line HNE1. Then we analyzed the specific role of miR-205-5p through functional assays by transfecting specific mimics and inhibitors. The results indicated that low expression of miR-205-5p restrained EMT progression of HNE1/DDP cells. Further studies on the mechanism of miR-205-5p manifested that PTEN was a downstream candidate gene of miR-205-5p, down-regulated PTEN expression could counteract the effect of miR-205-5p inhibitors, and the regulation of EMT by miR-205-5p on HNE1/DDP cells depended on the PI3K/AKT signaling pathway. Overall, our results indicated that miR-205-5p was targeting PTEN to regulate EMT through the PI3K/AKT pathway. This study will supply a new treatment target for advanced NPC.

Zhang P ，Lu X ，Shi Z ，Li X ，Zhang Y ，Zhao S ，Liu H ... -  《-》

miR-206 regulates cisplatin resistance and EMT in human lung adenocarcinoma cells partly by targeting MET.

Chen QY ，Jiao DM ，Wang J ，Hu H ，Tang X ，Chen J ，Mou H ，Lu W ... -  《Oncotarget》

Epithelial-mesenchymal transition is necessary for acquired resistance to cisplatin and increases the metastatic potential of nasopharyngeal carcinoma cells.

Zhang P ，Liu H ，Xia F ，Zhang QW ，Zhang YY ，Zhao Q ，Chao ZH ，Jiang ZW ，Jiang CC ... -  《-》

Gambogic Acid Improves Cisplatin Resistance of Bladder Cancer Cells through the Epithelial-Mesenchymal Transition Pathway Mediated by the miR-205-5p/ZEB1 Axis.

Bladder cancer (BC) is primarily treated with cisplatin-based chemotherapy, but the development of cisplatin resistance often leads to BC recurrence. This study is focused on assessing the potential of gambogic acid (GA) in mitigating BC cells' cisplatin resistance, along with an analysis of the underlying mechanism involved. Cisplatin was administered to human bladder transitional cell carcinoma cells (T24) at various concentration gradients to induce cisplatin-resistant (T24-DDP) cells. Several experimental groups were set: T24 group, T24-DDP group, T24-DDP+DDP group, T24-DDP+GA group, T24-DDP+DDP+GA group, T24-DDP+DDP+GA+miR-NC group, and T24-DDP+DDP+GA+miR-205-5p inhibitor group. The cell counting kit-8 (CCK-8) assay, Transwell migration assay, and scratch assay were respectively carried out for assessment of cell proliferation, invasion, and migration. Western blot analysis was conducted for detection of the protein expression of E-cadherin, ZEB1, Vimentin, N-cadherin, LRP, MRP, and P-gp in the cells, while the relative expression level of miR-205-5p was determined by qRT-PCR. In comparison with the T24-DDP group, cells in the T24-DDP+GA group showed enhanced sensitivity to cisplatin. Furthermore, as indicated by CCK-8 assay, GA improved T24-DDP cells' sensitivity to cisplatin, potentiated the effects of cisplatin, and exerted an inhibitory effect on the invasion, proliferation, as well as migration of T24-DDP cells. Through Western blot analysis, GA was revealed to significantly inhibit the expression of N-cadherin, E-cadherin, and Vimentin, as well as that of cisplatin-resistant proteins MRP, P-gp, and LRP in BC cells. In addition, shown by further experiments, GA promoted miR-205-5p expression and simultaneously inhibited ZEB1 expression within the cells. GA alleviates BC cells' cisplatin resistance through the epithelial-mesenchymal transition pathway mediated by the miR-205-5p/ZEB1 axis.

Mei Y ，Xu J ，Li W ，Chen S ... -  《-》