HPV16 E6和E7基因序列多态性与宫颈癌临床病理特征相关性

CORELATION BETWEEN THE POLYMORPHISM OF E6 AND E7 ONCOGENE OF HUMAN PAPILLOMAVIRUS TYPE 16 AND THE PATHOLOGICAL FEATURES OF CERVICAL CANCER

目的探讨宫颈癌人乳头瘤病毒16型(HPV16)E6和E7转化基因序列多态性,及其与宫颈癌临床病理特征的相关性。方法从77例宫颈癌组织中筛选出51例HPV16阳性标本,扩增E6及E7基因,PCR产物进行序列测定。应用DNAStar生物软件进行核苷酸和氨基酸序列的分析。结果宫颈癌组织中HPV16 E6共测得6个突变位点,均为错义突变;最常见的突变位点为T178G/A(D29E),突变频率为56.00%,T178G/A突变在不同分化程度、不同分期、不同肿瘤大小及有无淋巴结转移组的分布频率差异无显著性(P>0.05)。宫颈癌组织中HPV16 E7共测得4个突变位点,2个为错义突变;最常见的突变位点为A647G(N29S),突变频率为68.09%,A647G在中分化及低分化组的突变频率分别为56.67%、88.24%,两组间突变频率差异有显著性(χ2=4.98,P<0.05);A647G在不同分期、不同肿瘤大小、有无淋巴结转移组的分布频率差异无显著性(P>0.05)。结论青岛地区HPV16 E6基因T178G/A突变与宫颈癌的发生发展无关,HPV16 E7基因A647G突变与宫颈癌的分化程度呈负相关,可以作为评估宫颈癌恶性程度的指标。

Objective To investigate the polymorphism of HPV16 transforming gene E6 and E7 and its relationship with the pathological features of patients with cervical cancer. Methods Fifty-one HPV16-positive samples were screened form tissues of 77 cases of cervical cancer,E6 and E7 genes were amplified,and sequence analysis was done for PCR products. ResultsSix mutable points of HPV16 E6 gene were identified,which were missense mutation;the most frequently seen mutable point was T178G/A,with the mutation frequency of 56.00%,which was not significantly related with the differentiation,clinical stage,tumor size and lymph node metastasis（P〉0.05）.Four mutable points were identified in HPV16 E7 gene of the cancer tissues,two of which were missense mutation,the most commonly seen mutable point was A647G（N29S）,with its mutation frequency of 68.09%.The frequency of A647G in moderately-differentiated and poorly-differentiated group was 56.67% and 88.24%,respectively,the difference being significant between the two groups（χ2=4.98,P〈0.05）,but the differences of distribution frequency of A647G were not significant in terms of clinical stage,tumor size and lymph node metastasis（P〉0.05）. ConclusionIn Qingdao areas,the mutation of HPV16 E6 T178G/A is not associated with the pathogenesis of cervical cancer,and that of HPV16 E7 A647G is negatively correlated with the degree of differentiation,which can be used as a marker for estimating the malignancy of this condition.