【摘要】 目的细胞遗传学研究表明，３号染色体缺失是鼻咽癌常见的染色体异常之一。分子生物学研究表明，染色体３ｐ在鼻咽癌中出现高频率的等位基因杂合性丢失（ＬＯＨ）。本研究将进一步确定鼻咽癌３ｐ等位基因杂合性丢失的频率及范围。方法应用位于３ｐ２１２６区域１６个微卫星多态性位点，对２４例低分化鼻咽癌患者进行了ＬＯＨ分析。结果２４例患者中有１６例存在杂合性丢失（６６．７％）。丢失频率最高的两个位点是Ｄ３Ｓ１５６０（５０％，１１／２１）和Ｄ３Ｓ１６２０（５０％，９／１８）。在具有丢失的１６例患者中，８例显示为１个连续的多个相邻位点的杂合性丢失区域，５例患者存在２个或２个以上的杂合性丢失区。病例１，３，４，７，８，１０，１６，１７，１８，１９和２２在Ｄ３Ｓ１５９７和Ｄ３Ｓ１２９７之间，表现为一个不同大小的杂合性丢失区。结论最小共同丢失区位于Ｄ３Ｓ１５６０Ｄ３Ｓ１６２０（３ｐ２５．３２６．２）之间，提示该区域有一个尚未克隆的、与晚期鼻咽癌明显相关的抑癌基因。更多还原

【Abstract】 Objective To determine the frequency and extent of loss of heterozygosity (LOH) on chromosome 3p in nasopharyngeal carcinoma(NPC). Methods Sixteen loci on chromosome bands 3p21 26 in 24 tumors was studied by using microsatellite analysis. Results LOH on 3p21 26 was found in 16 of 24 tumors (66.7%). The highest frequency of the allelic loss was found in two adjacent loci D3S1620(50%, 11/22) and D3S1560 (50%, 9/18). Eight cases showed LOH in one contiguous region and 5 cases in more than one region. Sample 1, 3,4,7,8,10,16,17,18,19, and 22 had a contiguous stretch of allelic loss between D3S1297 and D3S1597. Conclusion The smallest common LOH/deletion region seems likely to lie between D3S1620(3p26.2 26.3) and D3S1560(3p25.3). The allelic loss map defined here will facilitate finer mapping of putative tumor suppressor gene loci and positional cloning of such genes, which may play a role in carcinogenesis of NPC.更多还原