HBV基因型、变异、X蛋白与HCC相关性的研究

Correlation of the genotype and mutation of HBV and X protein with HCC

目的了解HBV 病毒基因型、变异位点1762/1764 和1896、X 蛋白与肝细胞癌的关系，进一步探讨肝癌的发病机理，为肝癌的防治及早期诊断提供理论依据。方法采用核酸扩增荧光定量及测序法检测慢性HBV 携带者、慢性乙型肝炎、乙肝肝硬化和乙肝合并肝癌患者共159 例血清标本的HBV 基因型及变异位点，采用免疫组织化学方法检测上述4 组肝组织中X 蛋白的表达情况，用半定量积分法进行结果判断。结果1. 在159 例慢性HBV 感染者中基因型B 型为56 例，占35.2％（56/159），基因型C 型为103 例，占64.8％（103/159），基因C 型在ASC、CHB、LC、HCC 四组中所占比例分别为44.0%（11/25），63.2%（36/57），85.7%（36/46），64.5%（20/31），差异有统计学意义（χ2 =8.462，P=0.037）。2. 在ASC、CHB、LC、HCC 四组中，基因C 型HBV 感染者发生BCP 变异的病例数所占比例分别为36.4%（4/11），75.0%（27/36），80.6%（29/36），75.0%（15/20），发生PC 变异的病例数所占比例分别为45.5%（5/11），66.7%（24/36），77.8%（28/36），70.0%（14/20），两种变异均多于基因B 型感染者，除ASC 组外，差异均有统计学意义（P <0.05）。3. X 蛋白的表达，以LC 组最高（阳性率71.7%），其次是HCC 组（71.0%）、CHB 组（59.6%）、ASC 组（52.0%），组间比较差异有统计学意义（P<0.05）。4. ASC 组、CHB 组、LC 组和HCC 组基因C 型HBV 感染者X 蛋白的阳性表达率分别为81.8%（9/11），72.2%（26/36），86.1%（31/36）和85.0%（17/20），大于基因B 型感染者X 蛋白的阳性表达率，即28.6%（4/14），38.1%（8/21），20.0%（2/10），45.5%（5/11），差异有统计学意义（P<0.05）。ASC、CHB、LC 和HCC 组中X 蛋白阳性表达的HBV 感染者BCP 变异阳性的比例分别为61.5%，73.5%，69.7%，81.8%，均高于BCP 变异阴性感染者所占比例，PC 变异阳性的比例分别为46.2%，67.6%，78.8%，63.6%，除了ASC 组外均高于PC 变异阴性感染者所占比例，但差异无统计学意义。结论HBV 基因型、变异位点1762/1764 和1896、X蛋白之间存在相互关系，与肝细胞癌的发生与发展有关。

Objective To understand the correlation of the genotype of hepatitis B virus(HBV), muta?tion loci of 1762/1764 and 1896, and HBV transactivator protein X with hepatocellular carcinoma(HCC) fortheoretical evidences in early diagnosis and therapy of this entity. Methods HBV genotypes and their mutationloci were tested by nucleic acid amplification in 159 blood samples obtained from asymptomatic chronic HBVcarriers, patients of chronic Hepatitis B, hepatitis B induced cirrhosis and HBV- associated HCC, and se?quenced by the auto genotype analyzer and measured with quantitative method. Expression of X protein in theliver tissues from the aforementioned 4 groups were detected by immunohistochemistry staining, and the resultswere estimated by semi-quantitative integration. Results 1) In the 159 cases infected with chronic HBV, 56were associated with genotype B(35.2%, 56/159) and 103 with genotype C (64.8%, 103/159). Genotype C ingroups of asymptomatic chronic hepatitis B virus carrier(ASC), patients of chronic hepatitis B(CHB), patientswith liver cirrhosis(LC) and HCC accounted for. The difference was significant(χ2 =8.462, P =0.037); 2)Muta?tions of basal core promoter(BCP)were 44.0%(11/25), 63.2%(36/57), 85.7%(36/46) and 64.5%(20/31), respec?tively for the four groups of HBV patients with genotype C, and cases with precore(PC) mutation were 45.5%(5/11), 66.7% (24/36), 77.8% (28/36) and 70.0% (14/20), respectively. Cases with two mutations were overthose with genotype B, and the difference was significant except for ASC group(P <0.05); 3) Protein X expres?sion was the strongest in group LC, with a positive rate of 71.7%, and came next by group HCC(71.0%), CHB (59.6%) and ASC(52.0%). The difference was significant among groups(P<0.05); 4)Positive rate of X proteinexpression in chronic HBV infectors with genotype C in group ASC, CHB, LC and HCC was 81.8%(9/11),72.2%(26/36), 86.1%(31/36) and 85.0%(17/20), and was higher than that in genotype B[28.6%(4/14), 38.1%(8/21), 20.0%(2/10) and 45.5%(5/11), respectively],with statistical difference(P <0.05). The proportion of HBV infectors with positiveBCP mutation and positive X protein expression in the four groups was 61.5%, 73.5%, 69.7% and 81.8%, and the proportion washigher than that in HBV infectors with negative BCP mutation. Positive PC mutation was 46.2%, 67.6%, 78.8% and 63.6%, whichwas higher than the proportion in HBV infectors with negative PC mutation except for group ASC, yet the difference was not sig?nificant. Conclusion HBV genotype C, mutation loci of 1762/1764 and 1896 and X protein are correlated with each other, suggest?ing that they are involved in the pathogenesis and development of HCC.