p73蛋白在正常人皮肤和表皮肿瘤中的表达

目的 探讨p73蛋白在正常人皮肤和不同表皮肿瘤皮损中的表达及意义。方法 应用免疫组化方法检测19例脂溢性角化病、16例基底细胞癌、11例Bowen病、5例鳞状细胞癌及10例正常人皮肤p73、p53、Ki67的表达。结果 在正常人表皮基底层、毛囊外毛根鞘最外层基底样细胞和皮脂腺生发细胞有p73的表达;在基底细胞癌和脂溢性角化病的基底样细胞、Bowen病中异形性明显的瘤细胞p73呈高表达,鳞状细胞癌和脂溢性角化病中的鳞状细胞呈弱阳性或不表达。脂溢性角化病、Bowen病、基底细胞癌、鳞状细胞癌之间p73蛋白表达差异有统计学意义(H=12.71,P<0.01),其中基底细胞癌的表达最强。Ki67在皮肤肿瘤之间差异也有统计学意义(H=14.12,P<0.01),但p53差异无统计学意义(H=2.058,P>0.05)。在各组样本中,p73的表达与p53、Ki67无显著相关性(P>0.05)。结论 p73蛋白可能在皮肤分化中起重要作用。

Expression of p73 in Benign and Malignant Epidermal Tumors and in Normal Skins

Objective To investigate the expression of p73 protein in normal skins and lesions of benign and malignant epidermal tumors. Methods By immunohistochemical staining, the expression of p73, p53 and Ki67 was examined in 19 cases of seborrheic keratosis (SK), 16 basal cell carcinoma (BCC), 11 Bowen's disease (BD), 5 squamous cell carcinoma (SCC),as well as in 10 normal skin controls. Results In normal skin, p73 protein was found to distribute in the basal cells of the epidermis, basal cells in the outer root sheath of the hair follicles, and the germinative cells in the sebaceous glands. p73 was expressed strongly in the basal cell-like cells of BCC and SK lesions, and in the atypical cells of BD lesions, but weakly or even negatively in the tumor cells of SCC lesions and the squamous cell-like cells of SK lesions. There was significant difference in the expression of p73 among the SK, BD, BCC and SCC lesions (H=12.71 ,P < 0.01); the strongest expression was found in the BCC lesions. Comparing all the tumors evaluated, significant difference was found in the expression of Ki67 antigen (H = 14.12, P < 0.01) but not in the expression of p53 (H = 2.058, P < 0.01). No correlation was observed between the p73 and p53 distribution or between the p73 and Ki67 expression. Conclusion The present study shows that p73 protein is likely to play an important role in epidermal differentiation.