Yu Qiang, Zheng Baijun, Ji Xiang, Li Peng, Guo Zhengtuan
Department of Paediatric Surgery, The Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an 710004, China.
Department of Paediatric Surgery, Xi'an International Medical Center Hospital, Xi'an 710100, China.
Acta Biochim Biophys Sin (Shanghai). 2021 May 21;53(6):739-747. doi: 10.1093/abbs/gmab047.
Wilms tumor is a rare kidney malignancy primarily developed in children. Treatment for Wilms tumor includes surgery, radiotherapy, and chemotherapy. Recent studies have demonstrated that microRNAs (miRNAs) play important roles in regulating Wilms tumor development. In this study, we aimed to elucidate the expression and function of miR-378c in Wilms tumor. Quantitative real-time PCR (qRT-PCR) results showed that miR-378c was downregulated in Wilms tumor tissues and cell lines. Functionally, further CCK-8, would healing, and transwell assays revealed that overexpression of miR-378c impaired Wilms tumor cell growth and metastasis in vitro. In addition, xenograft assay showed that miR-378c overexpression inhibited Wilms tumor development in vivo. Mechanistically, luciferase reporter assay confirmed that miR-378c directly targets CAMKK2 in Wilms tumor. qRT-PCR and western blot assays demonstrated that CAMKK2 was highly expressed in Wilms tumor tissues and cell lines. Rescue experiments were performed to further evaluate the functional relationship between miR-378c and CAMKK2. Overexpression of miR-378c suppressed Wilms tumor cell metastasis via negatively regulating CAMKK2 expression. Consistently, inhibition of miR-378c enhanced Wilms tumor cell malignancy behavior via augmenting CAMKK2 expression, which could be abrogated by CAMKK2 knockdown. In summary, our findings suggest that miR-378c inhibits the development and metastasis of Wilms tumor via negatively regulating CAMKK2 expression, which could be utilized to develop new therapy strategy.
肾母细胞瘤是一种主要发生于儿童的罕见肾脏恶性肿瘤。肾母细胞瘤的治疗方法包括手术、放疗和化疗。最近的研究表明，微小RNA（miRNA）在调节肾母细胞瘤的发生发展中起重要作用。在本研究中，我们旨在阐明miR-378c在肾母细胞瘤中的表达及功能。定量实时聚合酶链反应（qRT-PCR）结果显示，miR-378c在肾母细胞瘤组织和细胞系中表达下调。在功能上，进一步的CCK-8、伤口愈合和Transwell实验表明，miR-378c过表达在体外损害肾母细胞瘤细胞的生长和转移。此外，异种移植实验表明，miR-378c过表达在体内抑制肾母细胞瘤的发展。机制上，荧光素酶报告基因实验证实miR-378c在肾母细胞瘤中直接靶向钙调蛋白依赖性蛋白激酶激酶2（CAMKK2）。qRT-PCR和蛋白质免疫印迹实验表明，CAMKK2在肾母细胞瘤组织和细胞系中高表达。进行了挽救实验以进一步评估miR-378c与CAMKK2之间的功能关系。miR-378c过表达通过负向调节CAMKK2表达抑制肾母细胞瘤细胞转移。同样，抑制miR-378c通过增强CAMKK2表达增强肾母细胞瘤细胞的恶性行为，而CAMKK2基因敲低可消除这种增强作用。总之，我们的研究结果表明，miR-378c通过负向调节CAMKK2表达抑制肾母细胞瘤的发生发展和转移，这可为开发新的治疗策略提供依据。
