KCTD12负调控HDAC4抑制宫颈癌细胞转移机制研究

Targeted therapy of the recurrent and metastatic cervical cancers is still an urgent problem to be solved. Here, we found that KCTD12 represses the metastasis of cervical cancer cells via promoting RhoB expression at transcriptional level. However KCTD12 is not a transcriptional factor. Therefore we speculated the transcription factors involved in this process. Given HDACs are generally associated with repressed gene transcription, including RhoB. We firstly detected the interaction between KCTD12 and HDAC4 by co-IP. In addition, the overexpression of HDAC4 reverse the effect of KCTD12 promoting RhoB expression by dual luciferase reporter gene assay. These data indicate that HDAC4 may play an important role in the mechanism of KCTD12 mediating RhoB regulation. Therefore, we will examine whether KCTD12 negatively regulates the nuclear localization of HDAC4 to inhibit metastasis of cervical cancer cells. Finally, we will uncover the mechanism, physiological function and clinical significance of KCTD12 negatively regulating HDAC4. Together, these results will find novel targets for diagnosis and prognosis of cervical cancer patients.

宫颈癌转移与复发仍是临床治疗亟待解决的问题。本项目发现KCTD12蛋白发挥抑制宫颈癌细胞转移作用，与调节RhoB蛋白表达相关。细胞水平检测确认RhoB受转录水平调节，但是KCTD12不是转录因子，因而推测另一转录因子协同其发挥调控作用。考虑到HDACs蛋白发挥RhoB转录抑制因子作用，本项目通过蛋白相互作用检测发现KCTD12与HDAC4存在相互作用，利用双荧光素酶报告基因检测过表达HDAC4逆转KCTD12对RhoB的正向调控作用，提示HDAC4是KCTD12调控RhoB蛋白表达的关键分子。因此我们提出KCTD12负调控HDAC4的分子机制，即KCTD12通过阻止HDAC4核定位发挥调控RhoB转录和抑制宫颈癌细胞转移作用。本项目拟以宫颈癌细胞为模型，利用蛋白相互作用等检测技术，旨在揭示KCTD12负调控HDAC4的分子机制、生物学功能和临床意义，以期发现宫颈癌诊断和治疗新靶点。

宫颈癌是发展中国家女性高发的恶性肿瘤之一，存在术后复发的患者五年生存率不足10%的瓶颈。因此寻找宫颈癌复发和治疗的关键分子标记物是降低术后复发率和死亡率的关键。本项目利用体内和体外细胞功能实验、实时荧光定量PCR技术、荧光素酶报告基因系统、免疫共沉淀、免疫荧光定位研究等实验技术，系统研究了KCTD12对宫颈癌细胞转移的调节作用和分子机制。本研究发现KCTD12（potassium channel tetramerization domain containing 12）低表达促进宫颈癌细胞转移和黏附，其高表达抑制宫颈癌细胞转移和黏附。机制研究进一步发现KCTD12蛋白通过对RhoB的转录调节，调控宫颈癌细胞转移和黏附。而胞浆蛋白KCTD12蛋白则通过HDAC4对RhoB发挥转录调节作用。本研究地深入研究有望揭示KCTD12通过HDAC4发挥转录调节机制，为宫颈癌的复发和转移的筛查和治疗提供新靶点和思路。