PTEN在银屑病和皮肤非黑色素肿瘤中的表达和意义

The expression and significance of PTEN in the lesions of psoriasis and non-melanoma skin cancers

目的探讨PTEN(phosphatase and tensin homolog deleted on chromosome ten)与银屑病角质形成细胞(KC)增殖的关系,以及PTEN在炎症增生性疾病与皮肤恶性肿瘤中的作用机制。方法采用免疫组化法检测19例寻常性银屑病皮损、18例健康人正常皮肤、20例慢性湿疹、20例脂溢性角化症、20例基底细胞癌、20例皮肤鳞状细胞癌患者PTEN的表达。并利用计算机图像采集与分析系统对免疫组化结果进行平均光密度测定,统计学处理采用t检验。结果各组PTEN着色的平均光密度值在正常人为0.659±0.120、银屑病0.078±0.052、慢性湿疹0.711±0.162、脂溢性角化0.694±0.055、基底细胞癌0.704±0.165、皮肤鳞状细胞癌0.036±0.132。银屑病皮损、皮肤鳞状细胞癌PTEN着色的平均光密度值均低于正常皮损,三者之间相比差异均有统计学意义,其中皮肤鳞状细胞癌平均光密度值低于银屑病皮损。慢性湿疹、脂溢性角化和皮肤基底细胞癌中PTEN着色的光密度值高于正常皮肤,四者之间相比差异均无统计学意义。结论银屑病皮损中PTEN过低表达可能导致银屑病PI3K/Akt信号传导通路异常活化,引起KC过度增殖和异常凋亡,参与银屑病发病。

Objective To explore the relationship between PTEN（phosphatase and tensin homolog deleted on chromosome ten） and the proliferation of psoriasis keratinocytes, and the mechanism of action of PTEN in inflammatory proliferative dermatosis and skin malignancies. Methods Immunohistochemical method was used to detect the expression of PTEN in 19 cases of psoriasis vulgaris, 18 cases of normal skin, 20 cases of chronic eczema, 20 cases of seborrheic keratosis, 20 cases of basal cell carcinoma and 20 cases of squamous cell carcinoma. The average optical density of immunohistochemical results was measured by computer image acquisition and analysis system. The statistical analysis was performed by t-test. Results The mean optical densities of PTEN were 0.659 ± 0.120, 0.078 ± 0.052, 0.711± 0.162, 0.694± 0.055, 0.704±0.165 and 0.036±0.132 for normal skin, psoriasis, chronic eczema, seborrheic keratosis, basal cell carcinoma and squamous cell carcinoma respectively. To be compared with normal skin, psoriasis vulgaris and squamous cell carcinoma exhibited significantly smaller average optical density values of PTEN, while the value of squamous cell carcinoma was smaller than the psoriasis vulgaris. The difference between the every two groups had significant statistical significance. Chronic eczema, seborrheic keratosis and basal cell carcinoma showed slightly higher average optical density values of PTEN than normal skin. However, there were no significant differences among the above four groups. Conclusion Low expression of PTEN in psoriasis maybe induces abnormal activation of PI3K/Akt signaling pathway, and then causes the proliferation and abnormal apoptosis of keratinocyte, which may be involved in the pathogenesis of psoriasis.