ER基因CpG岛甲基化的表达及其临床意义

目的:研究ER基因表达及CpG岛甲基化状况与胃癌生物学行为和预后的关系.方法:分别应用免疫组化SP法和限制性内切酶PCR法分析91例胃癌ER的表达和30例胃癌ER墓因CpG岛甲基化的状况.结果:胃癌ER阳性率为38%(35/91),其中高分化腺癌10%(3/30),分别与低分化腺癌43%(13/30)、未分化腺癌53%(8/15)、粘液癌63%(5/8)及印戒细胞癌75%(6/8)比较皆具有显著性差异(P＜0.05);伴淋巴结转移组为55%(11/20),未转移组22.5%(9/40),差异有显著性(P＜0.05).正常胃粘膜ER基因CpG岛未甲基化,而胃癌呈高度甲基化40%(12/30)(P＜0.05).结论:ER在胃癌中的表达与浸润、转移有关,ER阳性胃癌生物学行为差,ER基因CpG岛甲基化可能是胃癌中ER失表达的分子机制.

Expression of Estrogen Receptor(ER) and Methylation of ER Gene CpG Islands in Gastric Carcinoma

Objective To investigate the expression of Estrogen receptor(ER)in gastric carcinoma and the methylation of ER gene CpG island and its correlation with gastric carcinoma Methods Expression of ER and methylation of ER gene CpG island in exon 1 were respectively examined by streptavidin-peroxidase conjugated method(S-P) and restriction endomuclease-polymerase chain reaction(PCR).Results Expressioin of ER was found in 38%(35/91)of gastric carcinoma.The frequency of ER gene positivity in well-diffentiated(43%),undifferentiated(53%),mucoid carcinoma(63%) and signet ring cell carcinoma(75%)(P<0.05).There was obvious difference between lymph node metastases(55%) and non-lymph node metastases(23%)(P<0.05).The aberrant methylatioin of ER gene CpG island in exon 1 was found and there was significant correlation with ER expression(P<0.05). Conclusion Expression of ER is related to differentiation,infiltration and metastasis in gastric carcinoma,and has the bad biological behavior and prognosis.Methylation of ER gene CpG island is a possible molecular mechanism for the loss of ER expression.