摘要
为了分离和克隆定位于7q32染色体区域的与鼻咽癌发病有关的抑瘤基因，检测了鼻咽癌活检组织及配对外周血标本中7q32微卫星DNA多态性位点的基因型，发现在7q32区域存在30％左右的杂合性丢失。从Internet中查询到定位于7q32区域的所有EST，对其中20个EST进行分析。RT－PCR和Northern杂交发现AA070437EST在鼻咽癌细胞株HNE1中表达微弱，而在正常鼻咽上皮原代培养细胞中表达强烈。差异RTMCR结果显示，鼻咽癌活检组织中有30．7％存在该EST表达下调或不表达。差异PCR和Southern杂交结果显示鼻咽癌活检组织DNA中存在该EST的29．1％等位基因丢失情况。与GeneBank等数据库比较表明该EST所代表的基因是一个新基因。结果表明AA070437EST在鼻咽癌发病中有明显负相关，是一个定位于7q32的鼻咽癌抑瘤基因候选者。
To isolate and clone tile tumor suppressor gene on chromosomal region 7q32 that corelated with the occurrence of human NPC, we detected the genotype of polymorphic microsatellite markers on 7q32 in 24 nasopharyngeal carcinoma biopsies and matched normal lymphocyte DNA. LOH was found in 30% biopsies. Using differential RT-PCR and Northern hybridization we compared the expression level of 20 EST on 7q32 between NPC cell line HNE1 and primary culture of normal nasopharyngeal epithelial cell, and found AA070437 EST expressed high in primary culture of normal nasopharyngeal epithelial cell, but very low in HNE1.Differential RT-PCR (dRT-PCR) analysis showed that the expression level of AA070437 was lower in 30.7% NPC biopses than in normal cell. Differential PCR (dPCR) showed that allelic loss of AA070437 was observed in 29.1% NPC biopses. This EST is a part of sequence of a new gene compared with GeneBank database. Our results showed that AA070437 EST negatively related with the occurrence of human NPC is a candidate of tumor suppressor gene of NPC on 7q32.
基金
国家863高技术计划!102-10-01-05
国家自然科学基金!39700158
关键词
鼻咽癌
杂合性丢失
EST
基因表达
Nasopharyngeal carcinoma (NPC)
Loss of heterozygosity (LOH)
Expressed sequence tag (EST)
Gene expression
