肿瘤的发生发展与癌基因的激活和抑癌基因的失活密切相关。大量研究发现,抑癌基因的失活与其启动子高甲基化有密切关联[1]。Ras相关区域家族1A(Ras assoc iation dom ain fam ily1A,RASSF1A)是2000年发现的新型候选肿瘤抑制基因(tumorsuppressor gene,TSG)。Ras基因是人类肿瘤 The occurrence and development of tumors are closely related to the activation of oncogenes and the inactivation of tumor suppressor genes. A large number of studies have found that inactivation of tumor suppressor gene promoter hypermethylation are closely related [1]. Ras associated region family 1A (RASSF1A) is a novel candidate tumor suppressor gene (TSG) discovered in 2000. The Ras gene is a human tumor