SOX9调控Wnt/β-catenin信号通路影响宫颈癌干细胞生物学特性的机制研究

The recurrence, metastasis and drug resistance of cervical cancer is a difficult problem to be overcome in the treatment of cervical cancer, which has become a hot research topic in recent years. We had successfully isolated human cervical cancer stem cells in previous study, and found, for the first time, SOX9 inhibited the initiation and progression of cervical cancer. Cervical cancer cells overexpressing（silencing）SOX9 showed decreased (increased) tumor sphere formation In vitro, and it indicated SOX9 could inhibit the self-renewal capacity of the cervical cancer stem cells . Former study demonstrated that Wnt/β-catenin signal pathway had been involved in a variety of cancer stem cells, and we also found that the overexpression (silence) of SOX9 in cervical cancer cells had reduced (elevated) the protein expression of β-catenin and C-myc. It remains to be confirmed by further studies whether SOX9 regulates cell proliferation and differentiation of cervical cancer stem cells through the Wnt/β-catenin signaling pathway. We try to perform this study by regulating the expression of SOX9 by siRNA and plasmid transfection, and detecting the changes of Wnt/β -catenin signaling pathway and the biological behavior of cervical cancer stem cells in order to clarify the regulatory role of SOX9 on cervical cancer stem cells, and to provide a potential new theory for prevention of recurrence, metastasis and even targeted therapy in cervical cancer.

宫颈癌的复发、转移和抗药性产生是宫颈癌治疗中亟待攻克的难题，近年成为研究热点。我们前期已成功分离出人宫颈癌干细胞，发现干细胞转录因子SOX9可抑制宫颈癌的发生与发展。过表达（干扰）SOX9后宫颈癌细胞体外成球能力减低（增强），提示SOX9可能抑制宫颈癌干细胞的自我更新能力。以往研究发现Wnt/β-catenin信号通路参与多种肿瘤干细胞干性的调节，我们前期研究发现过表达（干扰）SOX9使宫颈癌细胞β-catenin、C-myc蛋白表达减低（升高），那么SOX9是否通过影响Wnt/β-catenin信号通路调节宫颈癌干细胞的干性，尚待进一步研究。本项目拟通过siRNA和质粒转染技术在体内外对SOX9的表达进行干预，检测Wnt/β-catenin信号通路相关因子和宫颈癌干细胞生物学特性的变化，阐明SOX9对宫颈癌干细胞的调控作用及机制，为预防宫颈癌的复发、转移及靶向治疗提供理论与实验基础。

肿瘤干细胞是癌症发生、发展的主要动因，是引起肿瘤复发、转移和耐药产生的关键因素。肿瘤干细胞自我更新受到多种信号传导通路调控。本项目研究干细胞因子SOX9通过 Wnt 信号转导通路调节宫颈癌干细胞自我更新的分子机制，探讨 Wnt 信号通路对宫颈癌干细胞自我更新的调控机制。通过体外肿瘤球形成实验、NOD/SCID小鼠成瘤实验、RNA测序、TOP/FOP荧光素酶报告基因和qChIP等相关实验，我们研究发现SOX9激活Wnt信号转导通路并上调Wnt信号转导通路中的关键分子FZD10、β-catenin和c-Myc的表达、抑制DKK1的表达，进而促进宫颈癌细胞增殖及成瘤能力。证实SOX9通过激活Wnt信号转导通路可以上调干细胞相关标记物EPCAM、ALDH1A1、SOX2、NANOG和OCT4蛋白的表达，从而增强宫颈癌细胞自我更新能力、体内致瘤能力。这些结果表明SOX9通过激活Wnt信号转导通路可以增强宫颈癌细胞自我更新能力并促进宫颈癌细胞增殖及成瘤能力。本课题通过研究SOX9基于Wnt信号转导通路调节宫颈癌干细胞自我更新的调控机制，从而为宫颈癌靶向治疗技术的开发提供理论基础。