Gankyrin/NF-κB信号通路介导微囊藻毒素-LR致肝细胞恶性转化中的机制研究

Microcystin, which targets to liver, is the most harmful in the microcystin cyanobacterial blooms pollution hazards .Clarifying the molecular mechanisms of the toxicity is very important to find the protective drugs and reduce its population health hazards. Studies have shown that the expression of Gankyrin increases in normal liver tissue , anaplasia, carcinoma in situ and adenocarcinoma,which prompts an important role in the incidence of hepatocellular carcinoma, but the mechanism is not clear. NF-κB signaling pathway is confirmed in promoting the process of hepatocellular carcinoma after exposing to MC-LR . Recent research found that localized inhibition of NF-κB activity, will lead to hepatocellular carcinoma, and the chemical structure of Gankyrin which is the specific oncoprotein of hepatocellular carcinoma can inhibit the activity of NF-KB. Accordingly, Gankyrin may participate in the regulation of NF-KB signal through the malignant transformation process of liver cells contaminated by MC-LR. The purpose of this project is to establish the time-effect and dose-effect relationship of liver cells contaminated by MCs, and explore the molecular mechanisms of malignant transformation through Gankyrin signal pathway. And the project plans to provide the basic theory of malignant transformation molecular mechanism in the future.

微囊藻毒素是蓝藻水华污染中危害最为严重且具有靶向促肝癌的一类藻毒素，研究MCs毒性分子机制对研究保护性药物，减轻它对人群健康危害具有重要意义。研究表明Gankyrin在正常肝组织到间变、原位癌、腺癌中表达逐渐增强，提示其在肝细胞癌的发生中具有重要作用，但机制未明。NF-κB信号通路被证实在MC-LR促肝细胞癌的进程中有着重要作用，新近研究发现局部性抑制NF-κB的活性，将导致肝细胞癌，而肝细胞癌特异性的癌蛋白Gankyrin特殊的化学结构可抑制NF-KB的活性。据此，Gankyrin可能通过调控NF-KB信号参与MC-LR促肝细胞恶性转化。本项目旨在通过建立MCs染毒肝细胞时效、量效模型，从细胞和分子水平全面探讨Gankyrin在MCs诱导肝细胞恶性转化信号通路中的分子机制，为日后揭示MCs致肝细胞恶性转化的分子机制提供理论依据。

本研究目的是揭示Gankyrin分子调控的NF-κB信号通路在微囊藻毒素-LR（MC-LR）致肝细胞恶性转化中的作用。研究通过构建MC-LR 慢性染毒致肝细胞恶性转化的体内、外模型，检测了MC-LR对肝细胞造成的损伤。结果证实，MC-LR可以诱导肝细胞发生坏死、凋亡、氧化损伤（ROS活性氧升高、抗氧化酶表达增加）等多种损伤，甚至发生恶性转化。分析了Gankyrin分子及其介导的NF-κB信号通路在MC-LR致肝细胞恶性转化模型中的表达水平。发现在恶性转化过程中MC-LR可以促进肝细胞中Gankyrin分子表达升高，诱导NF-κB信号通路系列关键基因如β-catenin蛋白表达增加。同时，我们进一步构建了Gankyrin的慢病毒干扰载体稳定转染细胞，发现抑制Gankyrin表达后，MC-LR致细胞恶转能力减弱，表现为对细胞增殖、迁移能力的下降。因此，该研究为下一步揭示MC-LR致细胞恶性转化的分子机制提供了理论依据。