TRIO介导的侵袭性伪足形成在宫颈癌侵袭转移中的作用及机制研究

Cervical cancer is the most common cancer of the female reproductive system. Invasion and metastasis are the primary causes of treatment failure and subsequent death in cervical cancer patients. Invadopodia, a new concept proposed recently, provides new insights into the molecular mechanisms underlying tumor invasion and metastasis, which is still unknown in cervical cancer. In our previous work, TRIO amplification caused by increasing abundance of HPV integration in 5p15 impacted parametrium invasion and lymph node metastasis. Our preliminary experiments demonstrated that TRIO could induce cytoskeletal remodeling and ECM degradation by activating Rac1 and RhoA, which are critical factors in invadopodia formation. Therefore, based on the in vitro and vivo model, techniques of molecular biology and proteomics, we plan to further investigate signal pathways, such as Rac1/N-WASP, Arp2/3; Rho A/ROCK/N-WASP, Arp2/3; Rho A/MMPs, contributing to TRIO's effects on formation of invadopodia in cervical cancer. The purpose was to clarify the process of HPV 5P15 integration-TRIO amplification-invadopodia formation-ECM invasion and degradation the mechanism underlying cervical cancer invasion, providing valuable targets for clinical prediction and individual strategy of cervical cancer therapy.

宫颈癌是女性生殖系统最常见肿瘤，侵袭转移是导致预后差和治疗失败的主要原因。侵袭性伪足是实体瘤转移最新发现的直接证据和方式，在宫颈癌中尚无研究。本课题组前期发现在宫颈癌中HPV在5P15的整合增加，引起该片段TRIO基因扩增，并影响宫颈癌侵袭转移。预实验证实其可激活Rac1和Rho A，影响细胞骨架，增强运动能力，降解细胞外基质，为侵袭性伪足形成的重要作用方式和效应因子。本项目拟在前期证据的基础上，利用体内外模型，采用电镜、荧光显微镜、分子生物学及蛋白质组学等技术，探讨Rac1/N-WASP、Arp2/3； Rho A/ROCK//N-WASP、Arp2/3；Rho A/MMPs通路在宫颈癌侵袭性伪足形成中的作用，从而阐明HPV 5P15整合—TRIO扩增、上调—侵袭性伪足形成—基底膜浸润的过程，解析宫颈癌侵袭新机制。为开发新的预测、诊疗靶点提供依据。

宫颈癌是妇女生殖系统最常见的恶性肿瘤，虽然筛查和手术联合放化疗的防治模式已有效改善早期宫颈癌的预后，但转移、复发的宫颈癌却很难达到彻底根治，是病患死亡的主要原因。侵袭性伪足是实体瘤转移最新的直接证据和方式，在宫颈癌中尚无研究。本课题组前期发现在晚期宫颈癌中HPV在5P15的整合增加，引起该片段TRIO基因扩增。在该基金的支持下，课题组对TRIO在宫颈癌组织中的DNA扩增及RNA表达上调的现象进行了扩大样本量的验证，确认了TRIO再宫颈癌进展中的相关现象：即在有宫旁侵犯的病例中，在由淋巴结转移的病例中，TRIO的扩增及表达上调都是明显的。在分子实验中我们证实TRIO的过表达，明显激活了Rac1 GTPase/N-WASP、Arp2/3， Rho A GTPase/ROCK/N-WASP、Arp2/3通路，介导肌动蛋白聚合（F-actin—G-actin）；同时激活了Rho A GTPase/MMPs，介导了ECM溶解，使宫颈癌细胞产生侵袭性伪足，最终突破基底膜形成转移。本研究在课题的支持下阐明了HPV 5P15整合—TRIO扩增、上调—侵袭性伪足形成—基底膜浸润的过程，解析了宫颈癌侵袭转移新的分子机制，为确立TRIO及其上下游因子作为宫颈癌浸润预警标志物提供充分的科学依据。