School of Basic Medicine, Youjiang Medical University for Nationalities, No. 98 Chengxiang Road, Baise 533000, China.
Heilongjiang Province Key Laboratory of Cancer Prevention and Treatment, Mudanjiang Medical University, No. 3, Tongxiang Street, Mudanjiang 157011, China.
Int J Mol Sci. 2019 Jul 29;20(15):3705. doi: 10.3390/ijms20153705.
Accumulating evidence indicates that epithelial splicing regulatory protein 1 (ESRP1) can inhibit the epithelial-to-mesenchymal transition (EMT), thus playing a central role in regulating the metastatic progression of tumors. However, it is still not clear whether ESRP1 directly influences the cell cycle, or what the possible underlying molecular mechanisms are. In this study, we showed that ESRP1 protein levels were significantly correlated with the Ki-67 proliferative index ( = -0.521; < 0.01), and that ESRP1 overexpression can significantly inhibit cervical carcinoma cell proliferation and induced G1-phase arrest by downregulating cyclin A2 expression. Importantly, ESRP1 can bind to GGUGGU sequence in the 3'UTR of the cyclin A2 mRNA, and ESRP1 overexpression significantly decreases the stability of the cyclin A2 mRNA. In addition, our experimental results confirm that ESRP1 overexpression results in enhanced CDC20 expression, which is known to be responsible for cyclin A2 degradation. This study provides the first evidence that ESRP1 overexpression induces G1-phase cell cycle arrest via reducing the stability of the cyclin A2 mRNA, and inhibits cervical carcinoma cell proliferation. The findings suggest that the ESRP1/cyclin A2 regulatory axis may be essential as a regulator of cell proliferation, and may thus represent an attractive target for cervical cancer prevention and treatment.
越来越多的证据表明,上皮剪接调节蛋白 1(ESRP1)可以抑制上皮间质转化(EMT),从而在调节肿瘤的转移进展中发挥核心作用。然而,目前尚不清楚 ESRP1 是否直接影响细胞周期,或者潜在的分子机制是什么。在本研究中,我们表明 ESRP1 蛋白水平与 Ki-67 增殖指数呈显著负相关(= -0.521;< 0.01),并且 ESRP1 的过表达可以通过下调细胞周期蛋白 A2 的表达,显著抑制宫颈癌细胞的增殖并诱导 G1 期阻滞。重要的是,ESRP1 可以结合细胞周期蛋白 A2 mRNA 3'UTR 中的 GGUGGU 序列,并且 ESRP1 的过表达显著降低了细胞周期蛋白 A2 mRNA 的稳定性。此外,我们的实验结果证实,ESRP1 的过表达导致 CDC20 表达增强,CDC20 已知负责细胞周期蛋白 A2 的降解。本研究首次证明,ESRP1 的过表达通过降低细胞周期蛋白 A2 mRNA 的稳定性诱导 G1 期细胞周期阻滞,从而抑制宫颈癌细胞的增殖。这些发现表明,ESRP1/细胞周期蛋白 A2 调节轴可能是细胞增殖的重要调节因子,因此可能成为宫颈癌预防和治疗的有吸引力的靶点。