喉癌中转谷氨酰胺酶3基因杂合性丢失和表达研究

目的 探讨转谷氨酰胺酶3（transglutaminase 3,TGM3)基因在喉癌发生中的作用。方法 在TGM3基因内部及附近选择微卫星标记进行杂合性丢失（loss of heterozygosity,LOH)分析，于DNA水平间接检测72例喉癌患者中该基因的缺失；并进一步应用Northern杂交检测8例喉癌患者配对肿瘤及癌旁正常组织中TGM3基因的表达差异。结果 4个短串联重复序列（short tandem repeats,STR)位点均存在LOH，其中D20S17、D20S607、D20S99和D20S841位点的LOH频率分别为25.76%、20.00%、38.10%和18.75%，至少1个位点出现LOH的病例占61.11%，杂合性丢失与临床分期、淋巴结转移和分化程度无显著相关性；Northern杂交结果显示8例喉癌患者TGM3基因在正常组织中的表达比肿瘤组织显著增强。结论 TGM3基因在喉癌的发生中具有重要作用，具体机理有待进一步研究。

Study on the loss of heterozygosity and expression of transglutaminase 3 gene in laryngeal carcinoma

Objective To investigate the role of transglutaminase 3 (TGM3) gene in laryngeal carcinogenesis. Methods The authors detected the deletion indirectly through loss of heterozygosity (LOH) analysis at DNA level using 4 STR primers within and near TGM3 gene in 72 cases, and detected the differential expression of TGM3 gene in 8 cases of paired normal and cancerous tissue of laryngeal carcinoma by Northern blot. Results LOH was found existing in all of the microsatellite loci, and the LOH frequencies were 25.76%, 20.00%, 38.10% and 18.75% at D20S17, D20S607, D20S99 and D20S841 respectively; LOH concerning at least one polymorphism locus accounted for 61.11%. No correlation of clinical stage, lymph node metastasis and differentiation with the LOH of TGM3 gene was observed, P >0.05. TGM3 gene expressed significantly higher in normal tissues than in paired cancerous tissues. Conclusion TGM3 gene might play an important role in laryngeal carcinogenesis,and further researches will be needed to clarify the possible mechanisms.