皮肤鳞状细胞癌Smad2和Smad7的表达及其临床意义  

Expression of Smad2 and Smad7 Proteins in Cutaneous Squamous Cell Carcinomas and its Clinical Significance

作　　者：曾庆彪[1] 匡玉珍[1] 甘润良[1] 

机构地区：[1]南华大学第一附属医院病理科,湖南衡阳421001

出　　处：《南华大学学报（医学版）》2005年第4期461-465,472,共6页Journal of Nanhua University(Medical Edition)

摘　　要：目的检测Smad2和Smad7蛋白在皮肤鳞状细胞癌中的表达,分析其与皮肤鳞状细胞癌的病理分级及临床分期的关系。方法采用免疫组化SABC方法,检测60例皮肤鳞状细胞癌及10例正常皮肤石蜡包埋组织标本中Smad2和Smad7蛋白的表达与定位。采用图像分析技术对蛋白表达定量分析,比较正常鳞状上皮与不同分化程度鳞状细胞癌之间Smad2和Smad7蛋白表达的差异,分析Smad2和Smad7蛋白在皮肤鳞状细胞癌临床Ⅰ期至Ⅲ期的表达差异。结果正常皮肤和皮肤鳞状细胞癌的胞浆中都表达Smad2和Smad7。与正常鳞状上皮相比,皮肤鳞状细胞癌中Smad2的表达明显下调,而Smad7的表达明显上调(P<0.05)。皮肤鳞状细胞癌中,临床分期从Ⅰ期到Ⅲ期,Smad2的表达逐渐降低,其中Ⅰ期与Ⅲ期及Ⅱ期与Ⅲ期之间相比,差异有统计学意义(P<0.05),而Smad7的表达虽然逐渐增加,但差异无统计学意义。结论Smad2的表达下调及Smad7表达上调可能解除了TGF-β信号对细胞增殖的抑制作用,引起TGF-β的生长抑制信号缺失,使细胞生长失去控制,导致肿瘤的发生。TGF-β信号的下游分子Smad2的表达下调与皮肤鳞状细胞癌的浸润和转移有关。Objective To detect the expression of Smad2 and Smad7 in cutaneous squamous cell carcinomas （ SCC ） and normal squamous epithelia of skins, analyze the relationship of two Smad expressions in SCC of differentiation grades and clinical stages, thus explore the role of Smad2 and Smad7 in the pathogenesis of SCC. Methods Paraffin- embedded tissue sections containing normal squamous epithelia, well differentiated, moderately differentiated and poorly differentiated SCC were stained by SABC immunohistochemistry technique to detect the expression and location of Smad2 and Smad7. Protein immunoexpression was quantified by image analysis in the context of histopathological parameters. The different expressions of Smad2 and Smad7 among all the tissue sections were compared. Expression of Smad2 and Smad7 in different clinical stages of SCC was also analyzed. Results Expression of Smad2 and Smad7 located in cytoplasm in normal squamous epithelia and SCC of skins. There was statistically significant difference of Smad2 and Smad7 expression between normal skin and SCC （ P 〈 0.05）. Compared with normal group, expression of Smad2 was down - regulated and Smad7 was up - regulated in SCC. Obvious difference of expression of Smad2 demonstrated in stage Ⅰ or Ⅱ compared with stage Ⅲ （ P 〈 0.05）. However, there was no statistic difference of Smad7 though gradually increasing from stage Ⅰ to stage Ⅲ. Conclusions Down - regulation of Smad2 and up - regulation of Smad7 contribute to relieve the inhibition effect mediated by TGF β of cellular proliferation, which results in losing of cell growth suppression mediated by TGF β and contribute to tumor development or progression. Down - regulation of expression of Smad2, down - stream molecular of TGF β signaling pathway, was associated with invasion and metastasis of SCC.

关 键 词：皮肤 鳞状细胞癌(SCC) SMAD2 SMAD7 

分 类 号：R739.5[医药卫生—肿瘤] Q786[医药卫生—临床医学]