p-Stat3及其下游靶基因c-myc在喉鳞癌组织和细胞中的表达及意义

Expression and significance of p-Stat3 and its downstream gene c-myc in laryngeal squamous cell carcinoma tissue and cell line

目的:检测喉鳞状细胞癌(LSCC)组织及细胞中p-Stat3及其下游靶基因c-myc的表达,探讨这2种基因与本地区LSCC的发生、发展以及它们之间的相互关系。方法:采用免疫组织化学方法检测p-Stat3和c-myc在60例LSCC和30例声带息肉组织中的表达,探讨其相关性;免疫细胞化学法检测喉鳞癌细胞Hep2中p-Stat3和c-myc的表达,Western blotting法检测Hep2细胞在Stattic作用下p-Stat3和c-myc蛋白的表达情况。结果:LSCC组织中p-Stat3和c-myc蛋白的阳性表达率分别为65%和70%,与声带息肉组织相比差异有统计学意义(P<0.05)。LSCC组织中二者的表达呈正相关(r=0.273,P<0.05)。细胞免疫化学法显示,在Hep2细胞中存在有p-Stat3和c-myc蛋白的表达;在抑制剂Stattic作用下,Hep2细胞中p-Stat3和c-myc蛋白的表达水平随着浓度的增加逐渐下降。结论:在LSCC组织和Hep2细胞中存在有p-Stat3和c-myc的表达,Stattic可以特异性的抑制p-Stat3的表达,并下调其下游靶基因c-myc的表达,表明活化的p-Stat3信号通路可以成为LSCC基因治疗中一个重要的分子靶点。

Objective：To detect the expressions of p-Stat3 and c-myc in human laryngeal squamous cell carcinoma（LSCC）tissue and Hep2 cell line,and to find the relationship between them.Method：Immunohistochemistry was used to detect the expressions of p-Stat3 and c-myc in 60 cases of LSCC and 30 cases of vocal cord polyp tissue.The protein levels of p-Stat3 and c-myc in Hep2 cell line was determined by immunocytochemistry.Western blotting was used to determine the protein levels of p-Stat3 and c-myc in Hep2 after treating with different concentrations of Stattic.Result：The positive rates of p-Stat3 and c-myc were 65% and 70%in the LSCC tissue,compared with that in the vocal cord polyp tissue,with significant difference（P〈0.05）.The expression of p-Stat3 in LSCC tissue was associated with that of c-myc（r=0.273,P〈0.05）.The protein levels of p-Stat3 and c-myc were detected in the Hep2 cell line.Stattic inhibited Stat3 phosphorylation and c-myc in the Hep2 cell line in a concentration-dependent manner.Conclusion：p-Stat and c-myc were up regulated in the tissue of laryngeal squamous cell carcinoma and the Hep2 cell line.Stattic inhibits the constitutively active p-Stat3 signaling pathway,and downregulats the expression of c-myc.The strong constitutive p-Stat3 signaling pathway in LSCC makes p-Stat3 atarget for the development of novel therapeutic strategies.