HBV相关肝细胞癌患者HBV前S/S基因变异的分析

目的:研究肝细胞癌(Hepatocellular carcinoma,HCC)患者体内乙型肝炎病毒(Hepatitis B Virus,HBV)前S/S基因变异特点.方法:分别对9例乙型肝炎病毒表面抗原(HBsAg)阳性肝癌患者及其家族中11例HBsAg阳性者血清乙肝病毒前S/S基因PCR扩增克隆.测序并进行结构分析.找出基因变异活跃位点,再对两组资料作统计学分析.结果:除对照组中1例未能扩增出前S/S基因,仅能扩增出S基因,其它样本均扩增出前S/S基因片段.所有HBV株均为B或C基因型和adrq 或adw2血清型.肝癌患者来源的HBV在包膜蛋白抗体结合区点突变发生率较高,但与对照组相比,没有统计学差异(P＞0.05).肝癌组4例发生HBV前S区删除变异,具有特异性.与对照组(0/10)相比,有统计学差异(P＜0.05).结论:HBV前S/S区点突变可能与肝癌发生没有相关性,而前S区删除变异可能与肝癌发生有密切联系,应当对HBV感染者进行前S区基因变异监测.

ANALYSIS OF MUTATIONS IN PRES/S GENE OF HEPATITIS B VIRUS ISOLATED FROM PATIENTS WITH HBV-RELATED HEPATOCELLULAR CARCINOMA

Objective:To study the mutation characteristics of preS/S gene of hepatitis B virus(HBV) isolated from patients with hepatocellular carcinoma(HCC). Methods:HBV preS/S gene was amplified from HBV DNA extracted from sera of HCC patients with positive HBsAg(HCC group) and their family members with positive HBsAg(control group) by polymerase chain reaction (PCR)respectively. The subgenomic frames were subjected to cloning and sequencing. Sequence results were aligned with standard HBV sequence by BLAST and the data were analyzed statistically. Results:Except one case in control group only amplified S gene, all other samples have amplified preS/S gene of HBV. Phylogenetic analysis revealed that all HBV strains could be categorized into genotype B or C and serotype adrq or adw2. In contrast with control group, HBV strains isolated from HCC have high-rate-mutations in antibody binding regions of membrane protein but have no statistical significance in contrast with that of control group(P>0.05). Four cases in HCC group have deletion mutations in preS region and have statistical significance in contrast with that of control group(0/10, P<0.05). Conclusion:The point mutations in HBV preS/S gene may not be associated with the development of HCC, but deletion mutations in HBV preS/S gene may be closely associated with the development of HCC. It's important to survey the deletion mutations in preS/S gene on HBV carrier.