印记基因H19和胰岛素样生长因子Ⅱ在人子宫颈癌组织中印记缺失及意义

目的探讨人子宫颈癌组织中印记基因胰岛素样生长因子Ⅱ(IGF2)和H19印记缺失情况及意义。方法采用PCR技术筛选出40例人子宫颈癌组织及20例正常子宫颈组织中具有IGF2和H19基因杂合性病例,然后RT-PCR法检测IGF2及H19印记状态。结果IGF2基因在子宫颈癌组和对照组具有杂合性比率分别为52.5%(21/40)和65%(13/20);双等位基因表达率分别为47.6%(10/21)和7.7%(1/13),差异有统计学意义(P<0.05)。H19基因在宫颈癌组和对照组具有杂合性比率分别为47.5%(19/40)和55%(11/20);双等位基因表达率26.3%(5/19)和0,差异无统计学意义(P>0.05)。结论子宫颈癌中存在印记基因IGF2和H19的杂合性丢失(LOH)和印记缺失(LOI),IGF2和H19基因异常可能与子宫颈癌的发病相关。

Study of loss of imprinting of insulin-like growth factor Ⅱ and H19 genes in cervical carcinoma

Objective To study the loss of imprinting(LOI) of insulin-like growth factor Ⅱ(IGF2) and H19 genes in cervical carcinomas.Methods Polymerase chain reaction(PCR) method was used on DNA samples extracted from 40 cases of cervical carcinoma and 20 cases of normal control tissues to detect the heterozygosity of IGF2 and H19 genes.The LOI of IGF2 and H19 genes was detected by RT-PCR.Results The heterozygous frequency of IGF2 was 52% in cervical cancer samples.Comparatively,in 20 matched normal samples,13 cases showed the heterozygosity(65%).The biallelic expression of IGF2 was detected in 10 cases among the 21 informative cervical cancer samples(47.6%),however,1 case in 13 heterozygous samples of control group(7.7%)((P<0.05)).The heterozygous frequency of H19 in cervical cancer samples and control group were 47.5%(19/40) and 55%(11/20),respectively.5 cases of 19 informative cervical cancer sample showed biallelic expression of H19(26.3%),whereas no biallelic expression was demonstrated in the control group(0/11)(P>0.05).Conclusion LOI and LOH of IGF-2 and H19 genes are involved in cervical carcinomas.LOI of IGF2 and H19 may be involved in the initiation stage of carcinogenesis of cervical carcinoma.