鹅脱氧胆酸衍生物HS-1200在肝癌发生中DNA修复的作用机制

It is significant to prevent Hepatocellular carcinoma (HCC) because of its high incidence rate and poor prognosis. In present, it is reported that not only has HS-1200 been proved to have classical effect of bile acid-drug, but its anti-cancer activity has been wide accepted. The applicant have found that HS-1200 significantly inhibited viability of HCC cell lines, the growth inhibitory effect of HS-1200 was demonstrated to be derived from induction of apoptosis. However, HS-1200 did not inhibit viability and induce apoptosis of normal human hepatic cell line. Moreover, after treatment with HS-1200, the number of nodes in animal model of HCC was found to be significantly decreased and 8-OHdG, the marker of the DNA damage, was reduced..On the base of the previous studies, treating the mouse model of HCC with HS-1200,we are going to detect the concentration of 8-OHdG and the expression level of DNA repair enzyme Hmth1、α-hOGG1、β-hOGG1 in the hepatocytes , observe the correlation between DNA damage and DNA repair. According to the above data, combining the changes of the histology in mouse liver, we will prove that HS-1200 treatment on mouse model can prevent the occurrence of HCC. Furthermore, for revealing the mechanism of prevention of occurrence of HCC, we investigate the expression level of gene related to p53 signal pathway in the course of DNA repair. Our research may provide a novel thought and scientific basis for clinical prevention of HCC.

原发性肝癌发病率高，预后差，因此肝癌的预防具有重要意义。近期国内外研究显示鹅脱氧胆酸衍生物（HS-1200）既具有胆汁酸类药物的经典治疗效应，又有抗癌作用。申请者前期研究发现HS-1200能显著抑制肝癌细胞株生长并诱导其凋亡，对正常肝细胞株无明显影响；HS-1200干预大鼠原发性肝癌模型中显著降低了肝细胞DNA损伤标记物8-羟基脱氧鸟苷（8-OHdG）浓度，且肝癌结节明显减少。在此基础上，本课题拟通过HS-1200干预大鼠原发性肝癌模型，检测8-OHdG的浓度及肝细胞DNA修复酶Hmth1、a-hOGG1、β-hOGG1表达水平的变化，观察肝细胞DNA损伤、DNA修复的相关性，并结合大鼠肝脏组织学变化，发现并证实HS-1200具有预防肝癌的作用，进一步检测DNA修复过程中p53信号通路相关基因、分子的表达水平变化，揭示其作用机制和途径，为临床肝癌的预防提供新的思路和科学依据。

本课题自行合成鹅脱氧胆酸衍生物HS-1200，并进一步通过核磁共振频谱仪测该衍生物的氢谱图进一步证实。为进一步研究该衍生物在大鼠体内是否具有毒性作用，我们通过喂饲大鼠HS-1200，用自动生化分析仪测定大鼠肝功能、肾功能结果，并采用HE染色法观察肝组织、肾组织形态改变；电镜下观察肝组织、肾组织超微结构改变，判断HS-1200对大鼠肝肾功能的影响；结合血常规及骨髓涂片判断HS-1200对大鼠造血功能的影响。上述方法证实HS-1200对大鼠无毒性作用。