已建株鼻咽癌细胞的PLUNC基因启动子区序列多态性分析

目的检测人类标准鼻咽癌细胞中是否存在已知的PLUNC基因启动子-437bp-＋87bp区域的单核苷酸多态性（SNP）。以便进一步探索SNP与鼻咽癌的关系。方法采用PCR产物直接测序的方法,对7株体外培养的鼻咽癌细胞基因组DNA的PLUNC基因启动子区进行序列分析。结果发现7株PLUNC基因的启动子区皆存在已知的3个SNP位点（1888、2128和N2）和未知一个突变位点（N1）,其测观杂合度分别为85．7％、100％、100％和28．6％。其中3个已知SNP位点在筛查的细胞株中均存在T-C的突变,而且SUNE-1鼻咽癌细胞株的1888位点基因型为突变纯合子CC型。结论体外培养的标准鼻咽癌细胞株中存在已知的3个SNP位点（1888、2128和N2）的突变现象,且突变率为100％;1888位点鼻咽癌易患型（CC型）已在体外稳定建株;首次发现启动子-195bp区域N1突变位点。

Sequence Polymorphism Analysis of the Promoter Region of PLUNC Gene in Nasopharyngeal Cancer Cell Lines

Objective To nasopharyngeal cancer cells in detect the known single nucleotide polymorphism （SNP） of standard the region -437 bp N ＋ 87 bp of PLUNC promoter and to further explore the relationship between the nasopharyngeal carcinoma and SNP. Methods The PLUNC gene promoter sequences of seven nasopharyngeal cancer cells in vitro were PCR-amplified and then sequenced. Results Wee found that the seven cell lines contained three existent SNP sites （ 1888, 2128 and N2） and one unknown mutation point （ N1 ） in the promoter region of the PLUNC gene. The heterozygosity was 85. 7% , 100%, 100% ands28. 6%. The mutations of T → C on three known SNP sites existed in all cell lines. Furthermore, the genotype on 1888 SNP site in SUNE-1 nasopharyngeal carcinoma cell line was homozygous CC type. Conclusion The standard nasopha- ryngeal carcinoma cell lines in vitro also displayed the mutation phenomenon on the three knownSNP sites （1888. 2128 and N2）, with 100% mutation rate. Susceptibility gene type （CC type） of nasopharyngeal carcinoma on 1888 site had been stably established in vitro. N1 mutation site on the -195 bp region of the promoter was first discovered.