中文摘要：

表皮生长因子受体（epidermal growth factor receptor,EGFR）是HER/ERB-B跨膜受体激酶家族成员之一.EGFR的过表达促进细胞的增殖、存活和迁移,与许多实体瘤病人的低存活率相关.EGFR的表达受其启动子DNA甲基化调控.EGFR的转录沉默与CpG岛高甲基化相关.EGFR基因5′调控区包括1个富含GC的启动子,缺保守序列TATA盒和CAAT盒,有多个位点可以起始转录.本实验运用Bisulfite Sequencing PCR（BSP）方法检测了2种肿瘤细胞HeLa（EGFR＋）和K562（EGFR）EGFR基因-1300～＋600的甲基化状态.所检测目的片段共包含178个CpG位点.发现EGFR阳性与EGFR阴性两种细胞系的甲基化状态不同：宫颈癌细胞系HeLa转录起始点附近包括第一外显子区（-244～＋91）处于非甲基化状态,白血病细胞系K562转录起始点附近包括第一外显子区呈嵌合性的高甲基化状态.因此,第一外显子比启动子区的甲基化状态更能反映基因的活化状况.

英文摘要：

The epidermal growth factor receptor （EGFR） is a member of the HER /ERB-B family of transmembrane receptor kinases.Overexpression of EGFR confers advantages in cell proliferation,survival,and migration and correlates with decreased survival in multiple solid tumors.However,our knowledge regarding EGFR expression and regulation is still limited.CpG island hypermethylation is associated with transcriptional silencing.Thus,we looked into the methylation pattern of EGFR promoter and first exon region using bisulfite sequencing PCR （BSP）.The 5＇ regulatory sequence of the EGFR gene contains a GC rich promoter without any consensus sequences,such as TATA or CAAT boxes.Therefore,transcription starts at multiple initiation sites within the promoter region.Five sets of primers were designed to amplify nt-1300 to ＋ 600 （relative to ATG） region （which contains 178 CpG sites） of the human EGFR gene and methylation status were investigated in HeLa（EGFR ＋） and K562（EGFR-） cells.The two cell lines have different methylation patterns：low methylation was found in HeLa cells around the transcription start site,especially the first exon region from-244 to ＋ 91,and a mosaic dense methylation status in the human leukemia K562 cell line in the same region.Our results indicate that the methylation status of the first exon,rather than promoter region is a better indicator for the EGFR gene activity.