miR-146b-5p 在乳头状甲状腺癌细胞中调节 GPx-3 对过氧化物清除的作用。
MiR-146b-5p regulates the scavenging effect of GPx-3 on peroxide in papillary thyroid cancer cells.
发表日期:2023 Aug
作者:
Dan Zhang, Ji-Jun Deng, Qin Xu, Yang Zeng, Jun Jiang
来源:
ANTIOXIDANTS & REDOX SIGNALING
摘要:
谷胱甘肽过氧化物酶(GPx)是甲状腺滤泡细胞中重要的抗氧化酶。甲状腺乳头状癌(PTC)中谷胱甘肽过氧化物酶3(GPx-3)表达水平降低与预后不良相关,然而GPx-3在PTC中表达水平降低的原因尚不清楚。我们通过Western blotting法检测了乳头状甲状腺癌和相邻正常组织(n = 18)中GPx-3的表达。同时,我们利用生物信息学预测了GPx-3水平与性别、年龄、淋巴结转移、分期、BRAFV600E突变以及患者无复发生存率的关系,同时还利用生物信息学工具分析了GPx-3的潜在上游微RNA。我们通过双荧光酶报告基因实验和酶联免疫吸附测定(ELISA)验证了GPx-3与上游微RNA之间的关系。结果显示,在PTC中GPx-3的蛋白水平降低,分析公共数据库资料表明其下调表达可能与BRAFV600E突变有关。MiR-146b-5p在PTC中显著过表达。双荧光酶报告基因实验证实了miR-146b-5p对GPx-3 mRNA的3'-UTR的作用。在甲状腺癌细胞系TPC-1和BCPAP中靶向敲低miR-146b-5p后,GPx-3的表达水平增加,同时谷胱甘肽(GSH)向氧化谷胱甘肽(GSSG)的转化也有所升高。综上所述,乳头状甲状腺癌中GPx-3水平降低并影响细胞内过氧化物清除,这是由于miR-146b-5p的抑制作用。细胞内过氧化物的积累可能为甲状腺癌的预后不良做出贡献。
© 2023 作者们。
Glutathione peroxidase (GPx) is an important antioxidant enzyme in thyroid follicular cells. Reduced levels of glutathione peroxidase 3 (GPx-3) expression in papillary thyroid cancer (PTC) are associated with poor prognosis. However, the reason for the decreased expression level of GPx-3 in PTC is unclear.The expression of GPx-3 in papillary thyroid carcinoma and adjacent normal tissue (n = 18) was detected by Western blotting. Bioinformatics was used to predict the relationship between the level of GPx-3 and gender, age, lymph node metastasis, stage, BRAFV600E mutation, and recurrence-free survival of patients. The possible upstream microRNAs of GPx-3 were analyzed by bioinformatics tools also. We verified the relationship between GPx-3 and upstream microRNA by dual luciferase reporter assay and enzyme-linked immunosorbent assay (ELISA).The protein level of GPx-3 decreased in PTC, and analysis of public database datasets suggests that its decreased expression may be associated with the BRAFV600E mutation. MiR-146b-5p was significantly overexpressed in PTC. The dual luciferase reporter assay verified the effect of miR-146b-5p on 3'-UTR of GPx-3 mRNA. Knockdown of miR-146b-5p in thyroid cancer cell lines TPC-1 and BCPAP increased GPx-3 expression levels, accompanied by an increase in the conversion of glutathione (GSH) to oxidized glutathione (GSSG).In conclusion, the level of GPx-3 decreases in papillary thyroid carcinoma and impairs intracellular peroxide clearance, due to the inhibitory effect of miR-146b-5p. The accumulation of intracellular peroxides may contribute to the poor prognosis of thyroid cancer.© 2023 The Authors.