卵巢癌是死亡率第一的女性生殖系统恶性肿瘤，非编码RNA在其发生、发展过程中起着非常重要的作用，环状RNA作为一种“miRNA海绵”体与肿瘤等多种疾病密切相关。我们的前期研究发现PUM1基因及其外显子反向剪接形成的circPUM1在卵巢癌组织中高表达，在敲低circPUM1后，细胞凋亡明显，侵袭能力下降。生物信息学分析发现circPUM1反向剪接位点附近具有miR-615-5p、miR-6753-5p、miR-580-3p的结合位点，上述三种miRNA可分别结合癌基因NF-κB、MMP2、与CDK14的3’UTR区域。本项目拟在前期基础上证明这一科学假设：PUM1基因以circPUM1的形式，通过吸附并下调miR-615-5p、miR-6753-5p、miR-580-3p，调控NF-κB、MMP2、与CDK14等癌基因的表达，影响卵巢癌细胞增殖、侵袭、转移能力，参与卵巢癌的发生发展。

Ovarian cancer is the most lethal female reproductive system malignancy. It has been known that non-coding RNA plays an important role in the development and progression of tumor. As a kind of "miRNA sponge", circular RNA (circRNA) is closely related to various diseases, such as cancer. Our previous work has shown that PUM1 gene and its back-spliced circular transcripts (circPUM1) are highly expressed in ovarian cancer. Moreover, knocking out circPUM1 promotes cell apoptosis and inhibits cell invasion. Bioinformatics analysis reveals that miR-615-5p, miR-6753-5p and miR-580-3p binding sites can be found at back-splice junction sites of circPUM1. In addition, miR-615-5p, miR-6753-5p and miR-580-3p can bind to the 3'UTR of oncogene NF-κB, MMP2 and CDK14, respectively. On the basis of previous work, our project intends to demonstrate the scientific assumption: PUM1 gene, as the form of circPUM1, regulates the expression of NF-κB, MMP2 and CDK14, through sponging miR-615-5p, miR-6753-5p and miR-580-3p, and participates in the tumorigenesis and development of ovarian cancer.