乙型肝炎病毒基因型及亚型与YMDD、前C和C基因启动子变异的关系

目的 探讨乙型肝炎病毒(HBV)基因型及亚型与YMDD变异的关系,以及前C基因区终止密码变异(A1896)、基本核心启动子(BCP)区T1762/A1764变异在Ba、C1和C2三种基因亚型中的发生情况.方法 采用聚合酶链反应-限制性片断长度多态性(PCR-RFLP)法对211例服用拉米夫定后发生YMDD耐药变异的患者HBV进行基因型、基因亚型、A1896及T1762/A1764变异检测.结果 211份标本中B基因型占50.7%(1071211),C基因型占49.3%(104/211),与广东地区对照人群HBV基因型分布情况相比无统计学差异(χ2=0.508,P=0.476).进一步亚型分析发现,107份B基因型全部为Ba亚型;C基因型有C1和C2两种亚型,其中C1亚型占64.4%(67/104),C2亚型占35.6%(37/104),与广东地区对照人群C基因亚型分布情况相比也无统计学差异(χ2=0.043,P=0.836).A1896变异在Ba亚型中的分布最高(41/107,38.3%),C2亚型次之(13/39,33.3%),C1亚型最低(9/65,13.8%),变异在不同基因亚型中的分布有统计学差异(χ2=11.839,P=0.03).T1762/A1764变异在C1亚型中的分布最高(34/65,52.3%),C2亚型次之(17/39,43.6%),Ba亚型最低(23/107,21.5%),T1762/A1764变异在不同基因亚型中的分布有统计学差异(χ2=18.384,P＜0.001).结论 HBV基因型及亚型并不影响YMDD变异的发生,但3种基因亚型发生A1896及T1762/A1764变异的模式存在明显不同.     

乙型肝炎病毒基本核心启动子突变与基因型的关系

目的研究乙型肝炎病毒（HBV）基本核心启动子（BCP）突变与HBV基因型的关系。方法随机选取我院68例慢性乙型肝炎患者外周血，采用荧光定量PCR结合TaqmanMGB探针技术检测HBV基因型，并用基因扩增和DNA测序方法检测BCPT1762／A1764双突变。结果68例患者HBV分型中，B基因型20例，C基因型46例，B、C混合型1例，未分型（非B非C型）1例。66例B、C两基因型中，B基因型组T1762／A1764双突变5例，突变率25．0％（5／20），C基因型组T1762／A1764双突变24例，突变率52．2％（24／46），C基因型T1762／A1764双突变率明显高于B基因型（P〈0．05）。结论苏州地区慢性乙型肝炎患者基因型以C型和B型为主，C基因型比B基因型更易发生T1762／A1764双突变。     

福州市乙肝病毒基因型和基因亚型的分布及其与前C、C基因启动子变异的关系

目的 研究福州市乙肝病毒基因型和亚型分布及其与T1762/A1764、A1896变异的关系,为完善预防、诊断、治疗病毒感染的策略和方法提供科学依据. 方法 应用型特异性引物PCR法检测HBsAg阳性血清的基因型,应用PCR-RFLP方法检测基因亚型、T1762/A1764变异和A1896变异. 结果 282份HBsAg阳性血清样品中103份未能成功分型,其余179份样品中B基因型122份(68.2%),C基因型54份(30.2%),B C型3份(1.7%),未检测到其他基因型.随机选取的100份B基因型样品中,Ba亚型71份(71.0%),Bj亚型8份(8.0%),未能分亚型者21份(21.0%).54份C基因型样品中Ce亚型 31份(57.4%),Cs亚型 14份(25.9%),Ce Cs 1份(1.9%),未能分亚型者8份(14.8%).T1762/A1764变异标本9份(8.7%),Ce亚型变异率最高(29.2%),Ba亚型次之(3.3%),Cs和Bj亚型未检测到变异株,T1762/A1764变异在不同基因型和亚型间的分布差异有统计学意义(P＜0.05).A1896变异标本10份(10.0%),Ba亚型变异率最高(14.0%),Cs亚型次之(10.0%),Ce亚型最低(4.0%),不同基因型和亚型中的变异差异无统计学意义(P＞0.05).HBeAg阳性和阴性样品中的基因型和亚型分布差异无统计学意义(P＞0.05). 结论 福州市乙肝病毒以B、C基因型为主,Ba、Ce亚型占优势,HBV各基因型和亚型发生T1762/A1764、A1896变异的模式不同.     

江苏省启东市乙型肝炎病毒基因型与肝癌及核心启动子突变的关系

目的 对江苏省启东市肝癌高发区的HBV流行株进行基因型别鉴定,并分析其与肝癌的相关性. 方法自启东市肝癌高发区的182份血清标本中抽提HBV DNA,以PCR方法扩增HBV全基因或X基因,测序后与基因库中已知基因型的参照序列共同构建基因进化树,根据序列在进化树中的位置进行型别鉴定.率的比较采用χ 2检验或Fisher精确概率法. 结果对包含24例HBV携带者、11例慢性乙型肝炎患者及13例肝癌患者在内的48例患者的血清HBV全基因测序结果显示,44例(91.7%)为C2基因型,4例(8.3%)为B2基因型,未见A、D、E、F、G、H等型别,也未见B/C重组病毒.以X基因测序方法对182例患者血清标本的鉴定结果显示,C2和B2型分别占92.9%(169例)和5.5%(10例),另有1.6%(3例)为B2/C2混合感染.启东地区C基因型的感染率明显高于邻近上海地区的78.9%(χ2=12.252,P<0.01).在81例肝癌和77例肝炎患者中,B、C基因型HBV的分布差异并无统计学意义(P>0.05).核心启动子区T1762/A1764联合突变在C基因型中的发生率为70.3%,明显高于B基因型中的30.8%(P<0.05);T1766和A1768突变则仅见于C基因型病毒中. 结论启东地区HBV感染以C2基因型为主,但其与肝癌的发生未见明显相关性.C基因型中较易出现核心启动子突变.     

青岛地区乙型肝炎病毒基本核心启动子区基因突变与乙型肝炎病毒所致原发性肝癌的相关性

目的通过分析山东省青岛地区HBV核心启动子基因序列的突变特征,探讨其与乙型肝炎相关原发性肝癌的相关性。方法收取慢性乙型肝炎患者和乙型肝炎相关原发性肝癌患者的血清标本各60例,然后从中提取HBV DNA,采用聚合酶链反应(PCR)扩增、纯化、克隆后测序,根据S基因区的编码序列确定患者的基因型和血清型;分别将HBV核心启动子区的各序列结果与GeneBank中的HBV标准株做对比,用DNAMAN软件对基因序列进行突变分析。采用SPSS17.0软件进行统计学分析。结果 120例标本,HBV株均为B或C基因型,以C基因型为主,其中,HBV组的C基因型所占比率为83.33%,HCC组为90.00%(χ2=0.65,P=0.42);血清型均为adw2或adrq+。HBV基因组核心启动子区常见的点突变为C1653T、T1753V、C1754T及A1762T/G1764A,发生率分别为42.73%、86.36%、71.82%、38.18%。与慢性乙型肝炎患者相比,肝癌患者中发生率比较高的突变位点为C1653T(78.85%,χ2=52.58,P<0.001)及A1762T/G1764A(73.08%,χ2=50.88,P<0.001)。结论山东青岛地区HBV基因组常见为B、C基因型,其中以C型为主;核心启动子区突变发生率高,其中,T1753V与HCC发生无关,C1653T、A1762T和G1764A位点无论单独或是联合突变均与HCC发生密切相关。     

HBV C基因启动子变异及基因型与肝硬化的相关性研究

目的探讨乙型肝炎病毒(HBV)C基因启动子(CP)和前C区基因变异及HBV基因型与肝硬化的关系。方法通过DNA扩增、基因序列分析检测44例慢性乙型肝炎(CH)、29例肝硬化(LC)患者的血清HBVS基因序列确定其基因型,测定HBVCP和前C区序列确定其变异状况。结果LC患者CP双变异(nt1762A→T和1764G→A)发生率(72.4%)显著高于CH(45.5%),P<0.05;LC患者C型检出率(69.0%)显著高于CH(43.2%),P<0.05;C型HBV感染者的CP双变异发生率(69.2%)显著高于B型感染者(44.1%),P<0.05。结论CP双变异与C基因型密切相关,并且导致病情向肝硬化发展。     

乙型肝炎病毒基因型、BCP及PC区变异与拉米夫定治疗后HBV DNA反弹的关系

目的:探讨HBV基因型、C区基本核心启动子(BcP)及前C(PC)区变异与拉米夫定抗病毒治疗后HBV DNA反弹的关系.方法:应用多引物对巢式PCR法,PCR-序列分析法,检测拉米夫定治疗27例乙型肝炎患者(治疗组),以及19例从未用过抗病毒治疗患者(对照组)的HBV基因型PC区,BCP的突变位点.结果:27例HBV DNA反弹的患者9例检出G1896A变异率高于对照组(33.33% vs 5.26%,P<0.05),4例检出C1856T变异(14.81%).治疗组4份治疗前标本未检出G1896A、C1856T和BCP变异.与对照组比较,治疗组PC(G1896A)及BCP(A1762T G1764A)双变异的患者中B基因型的构成比增高,分别为75%和50%,C基因型的构成比下降,分别为25%和50%.其中在BCP(A1762T G1764A)变异患者中B、C基因型构成比与对照组比较有显著性差异(P<0.05).4例HBV DNA反弹患者治疗前未检出有基因变异,治疗后有2例检出变异,BCP变异1例,BCP PC变异1例.27例HBV DNA反弹患者BCP变异4例,PC变异2例,BCP PC变异8例.结论:BCP(T1762/A1764)变异、PC区(G1896A)变异可能与拉米夫定治疗后HBV DNA反弹有关.病毒变异导致的HBV DNA反弹可以是单基因变异引起,也可以是多个基因联合变异引起,拉米夫定治疗后B基因型患者更易发生A1762T G1764A变异.     

HBV基因型及A1762T/G1764A双位点变异在肝癌患者中的临床意义

目的:研究肝细胞癌(HCC)患者乙型肝炎病毒(HBV)基因型与基本核心启动子(BCP)基因区A1762T/G1764A双位点变异(BCP区双突变)之间的关系,探讨HCC的发病机制。方法:选择40例HCC患者作为研究组,40例慢性乙型肝炎(CHB)患者作为对照组,采用多对型特异性引物PCR扩增法进行基因分型及HBV基因多态性芯片检测BCP区A1762T/G1764A双位点变异。结果:40例HCC患者中有30例HBV DNA定量阳性,平均对数值为(6·53±1·31)copy/ml,将30例HBV DNA定量阳性的HCC及40例CHB患者的血清进行HBV基因分型及基因变异检测,结果显示30例HCC中HBV B基因型5例(16·7%),C基因型25例(83·3%);BCP区双突变共有20例(67·7%),其中B基因型1例,C基因型19例,BCP双突变率在B基因型和C基因型中分别为20%(1/5)和76%(19/25);40例CHB患者中B基因型32例(80%),C基因型8例(20%);BCP区双突变共有13例,其中B基因型8例,C基因型5例,BCP双突率在B基因型和C基因型中分别是25%(8/32)和62·5%(5/8)。结论:肝细胞癌的发生与BCP区A1762T/G1764A双位点变异有关,多发生在HBV C基因型的患者。     

黎族HBV感染者其病毒基因型及C基因启动子/前C区基因突变与肝硬化和肝癌的关系

HBV感染是一个严重的公共卫生问题.在中国,慢性乙型肝炎是导致肝硬化和原发性肝癌的主要危险因素之一[1].目前,根据HBV核苷酸变异＞8％,将HBV分为A～H8种基因型[2].有研究结果显示,HBV基因型、HBV基因组前C区(PreC)第1896位核苷酸G→A(G1896A)以及其启动子(BCP) 1762位核苷酸A→T和1764位核苷酸G→A的突变(BCP A1762T/G1764A)与病毒的复制、转录、抗原表达水平以及疾病的临床过程密切相关[3-4].黎族是海南岛的原住居民,目前关于海南岛黎族肝硬化及肝癌患者HBV基因型、PreC G1896A基因突变和BCP A1762T/G1764A基因突变流行病学分布的研究鲜见报道.本研究旨在了解HBV基因型、PreC G1896A基因突变和BCP A1762T/G1764A基因突变与海南岛黎族肝硬化及肝癌患者发病机制的关系.     

乙型肝炎病毒家族聚集性感染者的基因型和基因变异特征分析

目的:研究HBV家族聚集性感染者的基因型和基因变异特征．方法:选择HBV聚集性感染家族成员内部基因型完全相同的共27个家族84人,其中HBV 携带者(ASC)29例;慢性活动性肝炎(CAH)23 例;肝硬化(LC)21例;肝细胞癌(HCC)11例;用基因芯片法检验前C1896和BCP1762,1764双突变;用测序法检验HBV基因型,并设相应基因型的HBV感染对照组．结果:B型HBV家族聚集感染者ASC率显著大于C型家族(X2=5．0734,P=0．0243,P<0．05); 其BCP1762．1764双突变的发生率也显著低于 C基因型(X2=22．4000,P=0．0000,P<0．001)．两种基因型的家族聚集感染者组与相应的对照组相比在疾病临床类型方面均无显著差异．结论:检验HBV家族聚集感染者的基因型和／或BCP区1762、1764基因的双突变可以协助疾病的预测分析．     

乙型肝炎病毒感染者病毒基因型和亚型分布及其临床意义

目的研究不同类型乙型肝炎病毒（HBV）感染者中HBV基因型和亚型分布情况及其临床意义。方法应用基因型和亚型特异性引物聚合酶链反应法（PCR），对北京、长春、汉川，深圳，清远和南京等6个城市445份HBV感染者血清进行基因型及亚型分型，其中急性肝炎7例，无症状携带者36例，慢性乙型肝炎352例，肝硬化28例，肝细胞癌22例。通过对PCR产物测序确定其基因型，以验证该法的准确性。结果445份血清中，239例（53．7％）为C型，其中13例（5．4％）为C1亚型，135例（56．5％）为C2亚型，91例（38．1％）为非C1／C2亚型；145例（32．6％）B型，其中100例（69．0％）为Ba亚型，25例（17．2％）为Bj亚型，20例（13．8％）为非Ba／Bj亚型；61例（13．7％）为B型与C型混合感染，其中6例（9．8％）为Ba与C1亚型混合感染，3例（4．9％）为Bj与C1亚型混合感染，15例（24．6％）为Ba与C2亚型混合感染，8例（13．1％）为Bj与C2型混合感染，11例（18．0％）为Ba与非C1／C2亚型混合感染，7例（11．5％）为Bj与非C1／C2亚型混合感染，2例（3．3％）为非Ba／Bj亚型与C1亚型混合感染，3例（4．9％）为非Ba／Bj亚型与C2亚型混合感染，6例（9．8％）为非Ba／BJ亚型与非C1／C2亚型混合感染。未检测到其他基因型及亚型。在不同类型乙型肝炎病毒感染者中，B型，C型、B与C型混合感染及亚型分布差异有统计学意义，在肝硬化和肝细胞癌患者中C型所占比例较高（分别为78．6％和86．4％），无症状携带者中B型所占比例较高（72．2％）。但不同性别患者中，HBV基因型和亚型分布无差异。在HBeAg阳性和阴性感染者中，HBV基因型和亚型分布差异也有统计学意义。结论该6个城市HBV感染者中，以B2和C2亚型占优势，C基因型可能与肝硬化和肝细胞癌的发生有关。     

135例乙型肝炎病毒感染者基因分型及其临床分布

目的研究乙型肝炎病毒（HBV）感染者中HBV基因分型及其临床分布情况。方法应用基因型和亚型特异性引物聚合酶链反应（PCR）法，对鲁西地区135例HBV感染者血清进行HBV基因型及亚型分型。结果未分型11例，已分型124例。其中C型111例（C2基因亚型87例、非C1／C2亚型24例）；B型11例，其中Ba型8例、Bj型3例；B／C混合型2例均为BaC2亚型混和感染。在肝硬化和重度慢性乙型肝炎中C型所占比例较高，分别为100％、88％；无症状携带者中B型所占比例较高为8．51％；HBV基因型分型与性别无关。结论鲁西地区HBV感染者以C基因型为主，其中C2亚型占优势。     

N-ras gene mutation and hepatitis B virus infection in hepatocellular carcinomas in Guangxi,China

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HBV基因型、变异、X蛋白与HCC相关性的研究

【摘要】 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。     

Geographic characterization of hepatitis virus infections,genotyping of hepatitis B virus,and p53 mutation in hepatocellular carcinoma analyzed by in situ detection of viral genomes from carcinoma tissues: comparison among six different countries

We investigated the relationship of infection with hepatitis B virus (HBV) and hepatitis C virus (HCV) to p53 mutation in hepatocellular carcinomas (HCC) from six countries, including Japan, China, Korea, Vietnam, Spain, and the Unites States. For this purpose, we used formalin-fixed, paraffin-embedded liver tissues obtained from 449 patients with HCC to detect the viral and p53 genes by polymerase chain reaction (PCR). HBV was the most prevalent in Korea (69.1%), China (66.1%), Vietnam (60.5%), and Spain (38.6%). In contrast, HCV was the most prevalent in Japan (59.8%) and in the United States (41.5%). Type C of HBV was the most common genotype (78.6%) encountered in HCC in these countries. Importantly, among 125 intrahepatic HBV DNA-positive patients, 44 (35.2%) were serologically negative for HBsAg (occult hepatitis B). Based on PCR, immunohistochemical, serological, and clinical findings, 4.8% of HCC patients were diagnosed with non-B, non-C. A point mutation at exon 7 of p53 was detected in 20 of the 239 HCC samples examined, including those from 9 Chinese, 5 American, 2 Japanese, 2 Korean, and 2 Spanish patients, respectively. Interestingly, a point mutation with an amino acid substitution at codon 251 (Ile-->Asn) was detected frequently in 11 of 20 (55%) cases. A specific mutation induced by Aflatoxin B1 at codon 249 was seen in two patients, both Chinese. Our results suggest that genotype C of HBV may play an important role in hepatocarcinogenesis in different geographic regions, and that in situ detection of HBV genomes could be important for clarifying the agent(s) of unknown etiology related to HCC.     

Hepatitis B virus subgenotypes and basal core promoter mutations in Indonesia

AIM： To identify the distribution of hepatitis B virus （HBV） subgenotype and basal core promoter （BCP） mutations among patients with HBV-associated liver disease in Indonesia.
METHODS： Patients with chronic hepatitis （CH, n =61）, liver cirrhosis （LC, n = 62）, and hepatocellular carcinoma （HCC, n = 48） were included in this study. HBV subgenotype was identified based on S or preS gene sequence, and mutations in the HBx gene including the overlapping BCP region were examined by direct sequencing.
RESULTS： HBV genotype B （subgenotypes B2, B3, B4, 85 and B7） the major genotype in the samples, accounted for 75.4%, 71.0% and 75.0% of CH, LC and HCC patients, respectively, while the genotype C （subgenotypes C1, C2 and C3） was detected in 24.6%, 29.0%, and 25.0% of CH, LC, and HCC patients, respectively. Subgenotypes B3 （84.9%） and C1 （82.2%） were the main subgenotype in HBV genotype B and C, respectively. Serotype adw2 （84.9%） and adrq＋ （89.4%） were the most prevalent in HBV genotype B and C, respectively. Double mutation （A1762T/G1764A） in the BCP was significantly higher in LC （59.7%） and HCC （54.2%） than in CH （19.7%）, suggesting that this mutation was associated with severity of liver disease. The T1753V was also higher in LC （46.8%）, but lower in HCC （22.9%） and CH （18.0%）, suggesting that this mutation may be an indicator of cirrhosis.
CONCLUSION： HBV genotype B/B3 and C/C1 are the major genotypes in Indonesia. Mutations in BCP, such as A1762T/G1764A and T1753V, might have an association with manifestations of liver disease.     

Dominant role of hepatitis B virus and cofactor role of aflatoxin in hepatocarcinogenesis in Qidong,China

We assessed the separate and combined effects of hepatitis B virus (HBV), hepatitis C virus (HCV), and aflatoxin in causing hepatocellular carcinoma (HCC) in Qidong, China. A consecutive series of 181 pathologic-diagnosed HCC cases were studied for hepatitis B surface antigen (HBsAg), anti-HBc, HBV X gene sequence, anti-HCV, the 249ser-p53 mutation, and chronic hepatitis pathology. Each of the 181 incident HCC cases had markers for HBV infection and hepatitis pathology; only 6 of 119 cases were coinfected with HCV. The 249ser-p53 mutation was found in 54% (97/181) of HCC cases and in all 7 cases with tissue for analysis from the hepatitis cohort but in none of 42 matched cases from Beijing. The estimated cumulative dose of aflatoxin B1 in these 7 cases ranged from 0.13 to 0.49 mg/kg. Follow-up data through 13.25 years on a cohort of 145 men with chronic HBV hepatitis showed that the relative risk from aflatoxin exposure was 3.5 (1.5-8.1). A similar relative risk was found using 249ser-p53 mutation as a marker for aflatoxin exposure. In conclusion, HBV hepatitis is ubiquitous in Qidong HCC cases, whereas HCV contributes little to its risk. The 249ser-p53 mutation appears to result from coexposure to aflatoxin and HBV infection. Even modest levels of aflatoxin exposure tripled the risk of HCC in HBV-infected men.     

广西肝癌中HBV感染与N_ras基因突变的研究

AIM To observe the roles of N-ras gene mutation and hepatitis B virus (HBV) infection in the carcinogenesis of hepatocellular carcinoma (HCC) in Guangxi, China.METHODS The polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) and immunohistochemistry were used to detect N-ras gene mutation and HBV infection in 29 cases of HCC.RESULTS The aberration rates at codon 2-37 of N-ras were 79.31% in HCCs and 80.77% in adjacent non-tumorous liver tissues. More than 2 point mutations of N-ras gene were observed in 22 (75.86%) cases. HBsAg and HBxAg positive rates were 86.2% and 79.3%. There was a parallel tendency between HBV marker detections and the mutation rate of N-ras gene.CONCLUSION HBV infection and N-ras gene mutation may be involved in the carcinogenesis and development of HCC in Guangxi. Since the aflatoxin B1 contamination is one of risk factors for HCC in this area, it may contribute to the mutation of N-ras gene in carcinogenesis of HCC.INTRODUCTIONHepatocellular carcinoma (HCC) is one of common malignant tumors in People′s Republic of China. Guangxi is a high incidence area of HCC. Many factors are involved in hepatocarcinogenesis. Many studies revealed that hepatitis B virus (HBV) infection might be a risk factor for hepatocellular carcinogenesis. One theory for hepatocarcinogenesis is that the oncogene(s) may be transactivated by hepatitis B x antigen (HBxAg)[1]. It is found recently that activation of N-ras gene may be the molecular basis for the carcinogenesis and development of HCC[2,3]. There have been reports about overexpression of N-ras oncogene in human HCC[4], but a few dealt with the roles of N-ras gene mutation and HBV infection, and their relationship with HCC. We analyzed the N-ras gene mutation and HBV infection in HCC by polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) and immunohistochemistry in 29 cases of human HCC.     

Basal core promoter mutations of hepatitis B virus increase the risk of hepatocellular carcinoma in hepatitis B carriers

BACKGROUND & AIMS: Hepatitis B viral (HBV) genotype C is associated with the development of hepatocellular carcinoma (HCC) compared with genotype B; however, the virologic factors contributing to the pathogenic differences remain unknown. We investigated the prevalence of T1762/A1764 basal core promoter mutant in a cohort of 250 genotype B- or C-infected HBV carriers with different stages of liver disease to clarify a possible role for this mutant in hepatocarcinogenesis. METHODS: The sequences of basal core promoter of HBV genome were determined in 60 inactive HBV carriers and 190 patients with histologically verified chronic liver disease and HCC. RESULTS: Genotype C has a higher prevalence of T1762/A1764 mutation than genotype B (odds ratio, 5.18; 95% confidence interval [CI], 2.59-10.37; P < 0.001). The likelihood of T1762/A1764 mutation parallels the progression of liver disease, from 3% in inactive carriers to 64% in HCC patients (odds ratio, 20.04; 95% CI, 7.25-55.41; P < 0.001). By multiple logistic regression analysis, patients with T1762/A1764 mutation were significantly associated with the development of HCC than those without (odds ratio, 10.60; 95% CI, 4.92-22.86; P < 0.001), and the risk was observed for both genotypes B and C. In addition, the prevalence of T1762/A1764 mutation in younger HCC patients was comparable with older HCC patients but was significantly higher than that in age-matched inactive carriers, irrespective of genotypes. CONCLUSIONS: Our data suggest that HBV carriers with T1762/A1764 basal core promoter mutant are at increased risk for HCC and that this mutant may contribute to the pathogenesis of HBV infection.