角蛋白19在皮肤癌组织中表达特征的实验研究

Cytokeratin 19 expression in usual cutaneous carcinomas

目的 :了解角蛋白 19在皮肤鳞癌和皮肤基底细胞癌组织中的表达特征。方法 :选择皮肤鳞癌标本 6个和皮肤基底细胞癌标本 4个 ,分别切取癌组织各一块 ,同时切取正常皮肤组织 2块作对照 ,应用过氧化酶标记的链霉卵白素 (SP)免疫组化法 ,以小鼠抗人角蛋白 19型的单克隆抗体来检测角蛋白 19表达阳性细胞。结果 :正常皮肤组织只有表皮基底细胞层和附属器的部分细胞表达角蛋白 19:I级鳞癌组织中无角蛋白 19表达阳性细胞 ,但有部分细胞核大小不等 ,形态各异 ,而且细胞分布较紊乱 ,并有许多角化珠 ;Ⅱ级皮肤鳞癌有局灶性的角蛋白 19表达阳性细胞 ,这些细胞分布紊乱 ,细胞核大小不等 ,形态各异 ;Ⅲ级皮肤鳞癌和基底细胞癌组织内有大量的角蛋白 19表达阳性细胞 ,且分布紊乱 ,其核大小不等 ,形态各异。结论 :角蛋白 19在皮肤鳞癌组织中的表达特征与皮肤鳞癌的分化程度有关 ,分化程度越低 ,角蛋白 19表达越强 ,分化程度越高 ,角蛋白 19表达越弱 。

Objective: To study the expression characteristics of cytokeratin 19 (CK 19) in usual cutaneous carcinomas. Method: Immunohistochemical (streptavidin-biotin-peroxidase) technique was applied. CK 19 expression was evaluated in specimens including 2 normal skin tissues, 6 squamous cell carcinomas (SCCs) and 4 basal cell carcinomas (BCCs). Only cytoplasm expression was considered as specific. Result: CK 19 was expressed in the cytoplasm of epidermal basal, in the cells of the germinative hair matrix and the external root sheath of hair follicles, in the basal cells of the sebaceous gland and in the myoepithelial/basal cells of the sweat glands. All terminally differentiated cells were negative for CK 19. As for the immunostainings of tissue sections, the positive expression cells of CK 19 in BCCs and grade III SCCs were more than those in grade II SCCs, whereas grade I SCCs were negative for CK 19. Conclusion: These results indicated that the expression characteristics of cytokeratin (CK 19) in usual cutaneous carcinomas were associated with the grade of SCCs.