HBV基因组编码一段特殊序列促进病毒DNA的剪接剪接HBV（spHBV）变异体因为其不能编码。功能性多聚酶而不具备自主复制能力，但是其可以在野生型HBV（wtHBV）的存在下复制。尽管HBV复制的增加是HCC形成的一个主要因素，而spHBV已经被证实可以增加HBV的复制。但是spHBV与HCC发生的真正关系及关联特点仍未阐明。此外，相较于单一wtHBV感染，wtHBV与spHBV混合感染时wtHBV自主复制和HBV蛋白合成会显著增加，该研究中作者分析了spHBV水平随时间的变化情况，首次给出了关于spHBV和HCC发展之间关系的纵向分析结果。该研究选取了1997年至2012年慢性单一HBV感染发展为HCC并确诊的58名患者（47男，11女）的130份HBV阳性血清样本，47份样本来源于HCC确诊前，38份样本来源于HCC确诊时（3个月之内），45份样本来源于HCC确诊后，另有来自107名截至2012年6月无HCC的慢性单一HBV感染患者的107份HBV阳性血清样本作为对照组，其HBV病毒载量均≥1×104 copies/mL。所有的患者均接受抗病毒治疗，wtHBV和spHBV的DNA载量由实时定量PCR检测获得。结果显示，在慢性HBV感染患者中，超过80%的患者血清可通过实时定量PCR法检测到spHBV，HCC组患者血清spHBV水平中位数显著高于无HCC组患者（6.693% vs. 0.424%, p<0.001），在忽略HCC的情况下，亚洲HBV基因型（B/C）的慢性乙型肝炎患者的血清spHBV水平中位数显著高于欧洲HBV基因型（A/D）的患者，ROC分析显示使用实时定量PCR法测定血清spHBV的诊断试验临界值为7%，拥有45%的灵敏度和96%的特异度。为进一步研究血清spHBV水平的临床相关性，作者比较了患者血清spHBV与甲胎蛋白（α-fetoprotein, AFP）水平，结果显示二者存在很强的正相关性（τ=0.2701; p<0.001）。HCC组患者血清spHBV检出率为82%（106/130），58%（75/130）的样本的spHBV水平高于之前确定的诊断临界值7%。这75例样本中，有很大一部分（75%, 56/75）来自于HCC确诊时或确诊前，当只考虑这部分样本时，HCC诊断时间与血清spHBV水平之间有强关联性。单变量分析结果显示亚洲HBV基因型、病毒载量增加与血清spHBV水平增加有强相关性，多重回归分析结果显示血清spHBV水平在HCC确诊前以大约每年0.1%的速率增加。综上所述，该研究说明了HBV剪接在慢性HBV感染患者中十分常见，其亦在HCC确诊前有明显的增加。因此对慢性乙型肝炎患者HBV前基因组剪接情况的检测、也就是对血清spHBV水平的检测，或许可以成为一个 预测HCC发生的有效手段
BACKGROUND & AIMS:
The hepatitis B virus (HBV) genome encodes specific sequence elements which promote splicing of viral DNA. It has been previously suggested that spliced HBV (spHBV) variants promote viral replication and protein production, leading to hepatocellular carcinoma (HCC). In this study we have analysed changes in spHBV over time; providing the first longitudinal analysis of spHBV in relation to the development of HCC.
METHODS:
Serial serum samples were collected from 165 patients with chronic HBV monoinfection, including 58 patients who later developed HCC. Real time PCR was used to amplify and quantify wt and sp DNA loads.
RESULTS:
spHBV was detected in over 80% of patients with chronic HBV infection. Median serum spHBV levels were significantly higher in HCC patients than HCC-free control patients (p< 0.001). Univariate analysis revealed a strong correlation between time to HCC diagnosis and spHBV DNA levels (τ= 0.203; p= 0.016). Asian HBV genotype (p= 0.025) and increased viral load (p< 0.001) were also significantly associated with increased spHBV DNA levels. Multiple regression analysis revealed time to diagnosis of HCC, Asian HBV genotypes and viral load to be associated with increased spHBV DNA (model p< 0.001; R2= 0.189).
CONCLUSIONS:
HBV splicing is a common event during chronic infection and increases prior to diagnosis of HCC. Measurement of HBV splicingmay prove a valuable adjunct to be used in the identification of chronically infected patients who are at increased risk of developing HCC.
吉林大学第一医院肝病科 王诗尧 摘译
本文首次发表于[J Hepatol. 2013 Jun]
本文首次发表于[J Hepatol. 2013 Jun]
Hepatitis B virus splicing is enhanced prior to development of hepatocellular carcinoma.
AbstractBACKGROUND & AIMS:
The hepatitis B virus (HBV) genome encodes specific sequence elements which promote splicing of viral DNA. It has been previously suggested that spliced HBV (spHBV) variants promote viral replication and protein production, leading to hepatocellular carcinoma (HCC). In this study we have analysed changes in spHBV over time; providing the first longitudinal analysis of spHBV in relation to the development of HCC.
METHODS:
Serial serum samples were collected from 165 patients with chronic HBV monoinfection, including 58 patients who later developed HCC. Real time PCR was used to amplify and quantify wt and sp DNA loads.
RESULTS:
spHBV was detected in over 80% of patients with chronic HBV infection. Median serum spHBV levels were significantly higher in HCC patients than HCC-free control patients (p< 0.001). Univariate analysis revealed a strong correlation between time to HCC diagnosis and spHBV DNA levels (τ= 0.203; p= 0.016). Asian HBV genotype (p= 0.025) and increased viral load (p< 0.001) were also significantly associated with increased spHBV DNA levels. Multiple regression analysis revealed time to diagnosis of HCC, Asian HBV genotypes and viral load to be associated with increased spHBV DNA (model p< 0.001; R2= 0.189).
CONCLUSIONS:
HBV splicing is a common event during chronic infection and increases prior to diagnosis of HCC. Measurement of HBV splicingmay prove a valuable adjunct to be used in the identification of chronically infected patients who are at increased risk of developing HCC.
