鼻咽癌表达下调基因NASG3'UTR可变剪接分析及其在多种肿瘤中的表达

Analysis of Splicing Variants in NASG 3′UTR, Down Regulated in Nasopharyngeal Carcinoma,and Its Expression in Multiple Cancer Tissues

背景与目的:采用抑制性消减杂交技术已分离获得了人鼻咽组织特异性基因NASG。本研究对人鼻咽组织特异性表达且在鼻咽癌表达下调的NASG基因3'非编码区(untranslatedregion,UTR)的可变剪接进行分析,并考察NASG基因在多种肿瘤组织中的表达。方法:在NASG基因3'UTR存在可变剪接部位的两端设计引物进行RT-PCR扩增,分离扩增产物并测序。用RT-PCR检测NASG基因在鼻咽癌中的表达,采用了肿瘤表达谱阵列(cancerprofilingarray)杂交分析NASG基因在多种肿瘤组织的表达状况。结果:NASG基因3'UTR存在3种剪接产物,NASG基因在71%的鼻咽癌活检组织中表达下调,25%的肺癌组织中表达上调,而在其他肿瘤及其配对的正常组织未见明显表达。结论:NASG基因3'UTR存在3种剪接产物,NASG基因的表达异常是鼻咽癌和肺癌发生、发展过程中重要的分子事件。

BACKGROUND &OBJECTIVE: NASG gene, a tissue specific gene of human nasopharyngeal epithelium was isolated by suppression subtractive hybridization. This study was designed to analyze splicing variants in NASG 3′untranslated region (UTR) and its expression profiling in multiple cancer tissues. METHODS: The PCR primers were designed in NASG 3′UTR around the splicing variants and reverse transcription polymerase chain reaction (RT PCR) was performed. The PCR products were separated and sequenced. The expression patterns of NASG were detected by RT PCR among nasopharyngeal carcinoma (NPC) cell line HNE1, primary human embryo nasopharyngeal epithelial cells, NPC biopsies, and normal adult nasopharyngeal epithelial tissues. Its expression profiling in multiple cancer tissues were tested by cancer profiling array hybridization. RESULTS: There were three splicing variants in NASG 3′UTR. NASG was identified to be down regulated in NPC cell line HNE1 and 71%of the NPC biopsies, but up regulated in 25%lung of the cancer biopsies, and not express in other cancer tissues and normal tissues. CONCLUSION: There were three splicing variants in NASG 3′UTR. Its abnormal expression may be an important molecular event in NPC and lung cancer.