Zou Xinwei, Zhu Chenjie, Zhang Lin, Zhang Yi, Fu Fengqing, Chen Youguo, Zhou Jinhua
Department of Obstetrics and Gynecology, The First Affiliated Hospital of Soochow University, Suzhou, People's Republic of China.
Clinical Research Center of Obstetrics and Gynecology, Jiangsu Key Laboratory of Clinical Immunology, Soochow University, Suzhou, People's Republic of China.
Onco Targets Ther. 2020 Jan 9;13:225-235. doi: 10.2147/OTT.S227015. eCollection 2020.
Cervical cancer is the fourth most common cause of cancer-associated mortality in women worldwide. Previous studies have reported that microRNAs (miRNAs) are involved in multiple biological aspects of cancer progression by regulating gene expression. Here, we investigated the role of microRNA-708 (miR-708) in cervical cancer.
The expression levels of miR-708 in cervical cancer tissues and paired-normal cervical tissues were tested by quantitative polymerase chain reaction (qPCR). The interaction between miR-708 and Timeless was identified by bioinformatics method, dual-luciferase reporter assay, and Western blotting. The effects of over-expression of miR-708 on cell proliferation and cisplatin sensitivity were determined by Cell Counting Kit-8 (CCK-8) and colony formation assay. Cell cycle and apoptosis were analyzed by flow cytometry. DNA damage induced by over-expression of miR-708 was determined by comet assay. Expression levels of the genes involved in repair of DNA damage were analyzed by Western blotting.
MiR-708 was down-regulated in cervical cancer tissues compared with paired-normal cervical tissues. By bioinformatics method, Western blotting, and dual-luciferase reporter assay, we found that Timeless was a direct target of miR-708. Furthermore, miR-708 suppressed cellular viability, colony formation, promoted apoptosis, and induced DNA damage levels. MiR-708 also enhanced chemosensitivity of cervical cancer cells to cDDP via impairing the ATR/CHK1 signaling pathway.
We conclude that miR-708 suppresses cell proliferation, facilitates cisplatin efficacy, and impairs DNA repair pathway in cervical cancer cells. These results demonstrate that miR-708 might be a candidate therapeutic target for future cervical cancer therapy.
宫颈癌是全球女性癌症相关死亡的第四大常见原因。既往研究报道，微小RNA（miRNA）通过调节基因表达参与癌症进展的多个生物学方面。在此，我们研究了微小RNA-708（miR-708）在宫颈癌中的作用。
通过定量聚合酶链反应（qPCR）检测miR-708在宫颈癌组织和配对的正常宫颈组织中的表达水平。通过生物信息学方法、双荧光素酶报告基因检测和蛋白质印迹法确定miR-708与Timeless之间的相互作用。通过细胞计数试剂盒-8（CCK-8）和集落形成试验确定miR-708过表达对细胞增殖和顺铂敏感性的影响。通过流式细胞术分析细胞周期和凋亡。通过彗星试验确定miR-708过表达诱导的DNA损伤。通过蛋白质印迹法分析参与DNA损伤修复的基因的表达水平。
与配对的正常宫颈组织相比，miR-708在宫颈癌组织中表达下调。通过生物信息学方法、蛋白质印迹法和双荧光素酶报告基因检测，我们发现Timeless是miR-708的直接靶点。此外，miR-708抑制细胞活力、集落形成，促进凋亡，并诱导DNA损伤水平。miR-708还通过损害ATR/CHK1信号通路增强宫颈癌细胞对顺铂的化疗敏感性。
我们得出结论，miR-708抑制宫颈癌细胞的增殖，促进顺铂疗效，并损害DNA修复途径。这些结果表明，miR-708可能是未来宫颈癌治疗的候选治疗靶点。
