金属硫蛋白-1和CT23在肝细胞癌中的表达及意义

摘要

目的 探讨金属硫蛋白-1(MT-1)、癌-睾丸抗原CT23在肝癌细胞、原发性肝细胞癌(HCC)中的表达及其与临床资料的关系和意义,了解MT-1和CT23在HCC发生、发展中的联系,为进一步研究HCC的发生、发展机制和相应治疗措施提供实验依据.方法 运用RNA干扰、表达谱芯片、荧光定量PCR、免疫组化SP法检测CT23与MT-1在肝癌细胞、HCC组织及其癌旁组织中的表达;通过t检验分析癌组织及癌旁组织中MT-1、CT23的表达与患者性别、年龄、甲胎蛋白(AFP)、乙肝表面抗原(HBsAg)、肿瘤大小、肿瘤数目、有无转移、Edmondson分级、肝硬化的关系.结果(1)MT-1和CT23的阳性信号主要定位于细胞质,镜下呈棕黄色或棕褐色团块或颗粒状.(2)MT-1、CT23在HCC组织中的表达均较癌旁组织低(P＜0.05).(3)在HCC组织中,肿瘤Edmondson分级低、单发者MT-1表达高于肿瘤Edmondson分级高、多发者(P＜0.05),MT-1表达与年龄、性别、HBsAg、肿瘤大小、AFP、肝硬化、肝脂肪变性、有无转移无明显关系(P＞0.05);MT-1在癌旁组织中的表达与临床资料无明显关系(P＞0.05).(4)CT23的表达在HCC组织及癌旁组织中与临床资料无明显关系(P＞0.05).(5)肝癌细胞中CT23下调引起MT-1 mRNA上调,HCC组织及癌旁组织中,MT-1与CT23之间的蛋白表达无明显关系(P＞0.05).结论 MT-1在HCC组织中表达较癌旁组织中降低,且在Edmondson分级较高、肿瘤多发者中MT-1表达较低,可见MT-1与HCC的发生、发展密切相关,其机制可能与肝组织中MT-1下调后金属解毒能力下降、自由基堆积导致细胞进一步恶化相关.CT23下调后细胞中MT-1表达上升,提示CT23下调后肝癌细胞恶性行为的下调可能通过MT-1表达上调来实现,但相关性和具体机制尚不明确,有待进一步研究.%Objective To investigate the expression and clinical significance of MT-1 and CT23 in hepatoma cells and hepatocellular carcinoma (HCC) tissues, thus to explore the roles of MT-1 and CT23 in the occurrence and development of HCC, and to provide the experimental basis for further study on the mechanism and treatment of HCC. Methods The expression of CT23 and MT-1 in hepatoma cells, HCC tissues and adjacent non-tumor tissues were assessed by RNA interference (RNAi) technology, gene expression profiling technology, fluorescence-based quantitative PCR, and immunohistochemical staining. T-test was applied for statistical analysis. Results The positive signals of MT-1 and CT23 were mainly located in the cytoplasm, as brownish yellow or brown particles under the light microscope, respectively. MT-1 and CT23 expression were significantly lower in HCC tissues compared with adjacent non-tumorous tissues (P＜0.05). The expression of MT-1 in HCC tissues with lower Edmondson grades and single tumor was significantly higher (P＜0.05). There was no significant correlation between the expression of MT-1 and age, gender, HBsAg, AFP, tumor size, liver cirrhosis, fatty degeneration of the liver, or metastasis (P＞0.05). The expression of MT-1 in the adjacent tissues was not correlated with the clinical data (P＞0.05). The expression of CT23 in HCC tissues or adjacent tissues had no significant correlation with clinical data (P＞0.05). The down-regulation of CT23 in hepatoma cells caused the up-regulation of MT-1 mRNA. There was no significant correlation between the protein expression of MT-1 and CT23 in the HCC tissues and adjacent tissues (P＞0.05). Conclusion MT-1 is closely correlated to the occurrence and development of HCC. The mechanism may be related to the decrease of metal detoxification and free radical accumulation caused by the down-regulation of MT-1 in the liver. After the down-regulation of CT23, the expression of MT-1 increases in the cells. It is suggested that the down-regulation of malignant behavior of hepatoma cells after the down-regulation of CT23 may be achieved through the up-regulation of MT-1 expression, but the correlation and specific mechanism are not yet clear, which needs further study.