miR-206 的过表达通过靶向 MAP4K3 降低甲状腺乳头状癌对优甲乐的耐药性。

Over-expression of miR-206 decreases the Euthyrox-resistance by targeting MAP4K3 in papillary thyroid carcinoma.

机构信息

Department of Head & Neck Surgery, Jiangsu Cancer Hospital, Jiangsu Institute of Cancer Research, The Affiliated Cancer Hospital of Nanjing Medical University, Nanjing, 210009, PR China.

Department of Thoracic Surgery, Jiangsu Cancer Hospital, Jiangsu Institute of Cancer Research, The Affiliated Cancer Hospital of Nanjing Medical University, Nanjing, 210009, PR China.

出版信息

Biomed Pharmacother. 2019 Jun;114:108605. doi: 10.1016/j.biopha.2019.108605. Epub 2019 Mar 21.

DOI:10.1016/j.biopha.2019.108605

PMID:30904818

Abstract

PURPOSE

microRNAs (miRNAs) play a critical role in drug resistance of multiple cancers including papillary thyroid carcinoma (PTC), indicating the potential of miRNAs as chemoresistance regulators in cancer treatment. The aim of this paper is to explore the relationship between miR-206 and chemoresistance of PTC.

METHODS

qRT-PCR was conducted to examine the expression of miR-206 in PTC tissues, parental and TPC-1/euthyrox. The CCK-8 assay, EdU assay and flow cytometry were performed to test cells viability, proliferation and apoptosis, respectively. Luciferase reporter assay was used to confirm the potential target of miR-206. Western blotting analysis was performed to evaluate the expressions of related-proteins.

RESULTS

miR-206 was significantly down-regulated in PTC tissues, parental and TPC-1/euthyrox. Moreover, the expression of miR-206 was exceptionally lower in TPC-1/euthyrox cells than that in TPC-1 cells. Furthermore, we found that over-expression of miR-206 could notably decrease the IC values both in TPC-1 and TPC-1/euthyrox cells, which indicated that miR-206 played an essential role in the euthyrox resistance in PTC. In addition, up-regulation of miR-206 inhibited the proliferation, induced apoptosis, suppressed the expressions of multidrug resistance-related proteins, including p-gp, MRP, BCRP and LRP, in euthyrox-resistant PTC cells. Besides, over-expression of miR-206 could notably promoted the expression of NIS, an intrinsic membrane protein that mediates the active transport of iodide into the thyroid and other tissues, playing a critical role in the progress. Further, miR-206 was demonstrated to be able to bind to MAP4K3 and negatively regulated the expression of MAP4K3. Besides, MAP4K3 was clearly up-regulated in PTC tissues, parental and TPC-1/euthyrox cells, and down-regulation of miR-206 attenuated the effect of si-MAP4K3 on the euthyrox sensitivity in euthyrox-resistant PTC cells. Moreover, TPC-1/euthyrox cells transfected with miR-206 mimics could significantly inhibit the expressions of p-p38, p-JNK and p-Erk, which indicated that miR-206 might play an essential role in the euthyrox resistance in PTC by negatively regulating the p38 and JNK signaling pathway.

CONCLUSION

miR-206 contributed to euthyrox resistance in PTC cells through blockage p38 and JNK signaling pathway by targeting MAP4K3, providing a potential therapeutic application for the treatment of patients with euthyrox-resistant PTC in the further.

摘要

目的

微小 RNA（miRNAs）在包括甲状腺乳头状癌（PTC）在内的多种癌症的耐药性中发挥着关键作用，这表明 miRNAs 作为癌症治疗中化学耐药性调节剂的潜力。本文的目的是探讨 miR-206 与 PTC 化疗耐药性之间的关系。

方法

采用 qRT-PCR 检测 PTC 组织、亲本细胞和 TPC-1/甲状腺素中的 miR-206 表达。通过 CCK-8 测定、EdU 测定和流式细胞术分别检测细胞活力、增殖和凋亡。采用荧光素酶报告基因检测验证 miR-206 的潜在靶标。采用 Western blot 分析评估相关蛋白的表达。

结果

miR-206 在 PTC 组织、亲本细胞和 TPC-1/甲状腺素中均显著下调。此外，TPC-1/甲状腺素细胞中的 miR-206 表达明显低于 TPC-1 细胞。此外，我们发现 miR-206 的过表达可显著降低 TPC-1 和 TPC-1/甲状腺素细胞的 IC 值，这表明 miR-206 在 PTC 的甲状腺素耐药中发挥了重要作用。此外，miR-206 的上调抑制了增殖，诱导了凋亡，抑制了多药耐药相关蛋白的表达，包括 p-gp、MRP、BCRP 和 LRP，在甲状腺素耐药的 PTC 细胞中。此外，miR-206 的过表达可显著促进内在膜蛋白 NIS 的表达，该蛋白介导碘的主动转运进入甲状腺和其他组织，在进展中发挥关键作用。进一步研究表明，miR-206 可与 MAP4K3 结合并负调控 MAP4K3 的表达。此外，MAP4K3 在 PTC 组织、亲本细胞和 TPC-1/甲状腺素细胞中明显上调，下调 miR-206 可减弱 si-MAP4K3 对甲状腺素耐药性 PTC 细胞中甲状腺素敏感性的影响。此外，转染 miR-206 模拟物的 TPC-1/甲状腺素细胞可显著抑制 p-p38、p-JNK 和 p-Erk 的表达，这表明 miR-206 可能通过负调控 p38 和 JNK 信号通路在 PTC 的甲状腺素耐药中发挥重要作用。