湖北地区22例宫颈癌组织中HPV 16型LCR基因变异特点分析

HPV16LCR Gene Variation and Phylogenetic Analysis of 22Cases of Cervical Cancer in Hubei,China

目的:研究人乳头瘤病毒(HPV)16型LCR基因在湖北地区部分宫颈癌组织中的变异特点,通过系统发生学分析探讨宫颈癌患者感染的HPV16型变异株的流行型别及特征。方法:从22例宫颈癌手术切除标本中提取组织DNA,用HPV16LCR特异性引物进行PCR扩增,对扩增的LCR产物片段进行测序,用Paup 4.0软件使用邻接法对HPV16变异株进行系统发生学分析。结果:在22例宫颈癌组织中LCR基因存在着12个位点的基因变异。高频率突变位点有5个。其中第7 521位核苷酸由G变异为A,变异频率为100%;第7 730位核苷酸由A变异为C,变异频率为86.4%,第7 842位核苷酸由G变异为A,变异频率为77.3%,第7 714位由T变异为G,变异频率为31.8%;第7 930位核苷酸由C变异为T,变异频率为31.8%。HPV 16LCR中的5个高频位点,均位于可与多个转录因子结合的区域。对LCR基因进行的系统发生学分析表明,湖北地区流行的HPV16病毒株主要为亚洲型(As)变异体(77.2%),其次为欧洲型(E)(22.8%),没有发现非洲-1型(Af-1),非洲-2型(Af-2)和亚洲美洲型(AA)HPV16变异体。结论:湖北地区宫颈癌组织中LCR存在着一定程度的基因变异,其中一些高频位点与国内、外报道的结果有明显差异,可能是湖北地区LCR的突变热点。

Objeetive. To study the gene variation and the characteristics of human papilloma virus lb （HPV16） long control region （LCR） gene of cervical cancer patients in Hubei, China. Methods： DNA was extracted from 22 cervical cancer samples. Then LCR genes were amplified, and PCR products were sequenced using the HPV16 LCR specific primers. Multiple sequence alignments of the LCR sequence of the HPV samples were performed with ClustalX1.81 software. Phylogenetic analyses were performed by the neighbor-joining method. Results： HPV 16 LCR gene mutations were found in all samples of the cervical cancer. The mutation rate of LCR 7 521, 7 730, 7 842,7 714, and 7 930 in cervical cancer samples was 100%, 86.4%, 77.3%, 31.8%, and 31.8%, re- spectively. Phylogenetic analysis showed that Asian （As） variants of HPV16 are predominated in Hubei, China. European （E） varinats were also found existing in Hubei areas. No Asian Ameri- can （AA）, African-1 （Af-1）, African-2（Af-2） variants of HPV16 was found in this region. Conclusion. High frequency mutations of HPV16 LCR gene have been found in cervical cancer samples in Hubei, China. These results showed that the HPV16 variants prevalent in Hubei are different from the Europe and African variants.