新疆南部地区维吾尔族妇女宫颈癌组织中HPV-16型L2基因多态性分析

目的探讨新疆南部地区维吾尔族妇女宫颈癌组织中人乳头瘤病毒16型(humanpapillomavirus16,HPV16)L2基因的变异,并预测L2蛋白的功能变化。方法从19份中国新疆南部地区维吾尔族妇女宫颈癌活检组织标本中提取DNA,以此DNA为模板,PCR扩增HPV16L2全长基因,PCR产物直接测序或克隆后测序,分析新疆维吾尔族妇女宫颈癌组织HPV16L2基因多态性及HPV16L2蛋白功能的变化。结果PCR检测结果显示宫颈癌组织中HPV16L2阳性率为84.21%(1619);测序和序列分析表明L2基因核苷酸多处发生变异,并引起编码氨基酸的变异;L2基因在核苷酸水平上形成7种突变模式(XJL21～XJL27),各模式与HPV16原型比较,同源性在99.37%～99.79%之间;在氨基酸水平上形成5种突变模式,其中XJL1123突变模式占66.67%(812),是突变的主流模式,各模式与HPV16原型比较,同源性在98.31%～99.58%之间;以上突变引起HPV16L2蛋白疏水性和抗原性的改变,继而改变了L1蛋白的结构及功能。结论中国新疆南部地区维吾尔族妇女宫颈癌组织中HPV16L2基因发生多位点变异,并形成多种突变模式和突变主流模式;这些突变引起HPV16L2蛋白疏水性和抗原性的改变,提示HPV16L2基因突变可能与HPV16的系统发生以及病毒逃避机体免疫识别有关。

Polymorphism of HPV-16 type L2 genes from cervical carcinoma biopsies in southern Xinjiang Uygur women

Objective To study the mutations of HPV-16 type L2 genes of cervical carcinoma biopsies from Uygur women in southern Xinjiang, and to analyze the changes of L2 protein function. Methods The tissue DNA was extracted from cervical carcinoma biopsies. HPV-16 L2 genes were amplified by PCR, HPV-16 type L2 genes were sequenced and analyzed. Results The positive rate of HPV-16 L2 was 84.21%(16/19). We sequenced DNA found some mutations in comparison with the previously published sequence of prototype HPV-16 L2. Some of the mutations changed the triplet codes, subsequently led to changes of amino acids. The mutations of all twelve HPV-16 L2 fragments formed seven patterns(XJL2-1 to XJL2-7) at nucleic acid level. Compare to HPV-16 prototype, their homology was 99.37% to 99.79%. The mutations of all twelve HPV-16 L2 fragments formed five patterns at amino acid level, among the mutations XJL1-1/2/3 was by 66.67% (8/12). Conclusion HPV-16 type L2 genes from cervical carcinoma biopsies had some mutations in Uygur women from southern Xinjiang, and formed several patterns as well as mainstream pattern. The mutations of L2 proteins changed its hydrophobicity and antigenicity. The research suggested that the mutations of HPV-16 type L2 genes can explain HPV-16 phylogenesis and escaping from immune recognition.