S100A8基因在喉鳞癌发生中作用机制的研究

目的：研究S100A8与喉癌发生的关系,揭示炎症在喉癌发生中的作用.方法：应用RT-PCR、West-ern Blot、免疫组化检测S100A8表达,RNAi方法检测其功能、Transwell检测细胞侵袭力,TUNEL和流式细胞仪检测细胞凋亡,MTT检测细胞生长活性.结果：36例喉鳞癌组织中17例出现S100A8 mRNA表达上调（47.2%）,而7例喉部良性肿瘤中2例出现表达上调（28.5%）.13例病人喉鳞癌组织中7例S100A8蛋白表达增高.免疫组化分析喉鳞癌组织S100A8蛋白阳性率为54.3%.在高分化喉鳞癌组织为71.4%,而分化程度差的喉癌组织中阳性率为12.8%（P=0.023）.RNAi抑制S100A8基因使Hep2细胞凋亡率增高近9倍,使Hep2细胞侵袭力下降,影响Bel-2基因表达,但对Hep2细胞的IKKα表达无明显影响.结论：S100A8与喉鳞癌发生相关并参与喉鳞癌分化,S100A8基因具有抑制喉癌细胞凋亡,促进Hep2细胞侵袭的作用.S100A8基因可能部分通过NF-κB通路参与喉癌发生、发展,在此通路中S100A8基因位于p65下游.

The molecular mechanism of S100A8 gene in the pathogenesis of laryngeal squamous cell carcinoma

Objective：S100A8 （MRP8） ,deregulated in many other cancers,was found deregulation in laryngeal squamous cell carcinoma （LSCC） in our previous cDNA microarray. The present study is to explore the effect of S100A8 gene on the pathogenesis of LSCCs. Methods： Semiquantitative RT- PCR,immunohistochemical and Western blot were used to analyze expression of S100A8. RNA interference （RNAi） inhibited expression of mRNA to evaluate the gene function , TUNEL and Flow cytometer assay detected cell apoptosis, MTT assays cell proliferation. Results： S100A8 mRNA in 47.2% of LSCCs（17/36） were up - regulated compared to PANLs,but only 28.5% of benign tumors up -regulated （2/7）. S100A8 protein were up - regulated in 7 of 13 LSCCs. The positively stained frequencies of S100A8 in well,moderately and poorly - differentiated LSCCs were 71.4% ,53.8% and 12.5% ,respectively （ P = 0. 023, P = 0.14 ）. The rates of apoptosis of Hep2 cells after SI00A8 RNAi, reached to 17.32% , which enhanced nearly 9 - fold, and the invasion was inhibited, but had less effect on Hep2 cells proliferation. S100A8 RNAi affected the expression of BCL- 2 genes, but had no effects on p65, RELB, IKKa and IKKB genes, however,p65 RNAi showed down -regulation of S100A8 mRNA. Conclusion： S100A8 gene involved in the pathogenesis of LSCCs and regulated apoptosis and enhanced invasion of Hep2 cells. S100A8 gene may be related and interacted between NF -kB pathyway in laryngeal carcinoma.