Abstract: Objective To investigate the expression,clinical and pathological significance of NET-1 protein in skin squamous cell carcinoma(SSCC).Methods The polyclonal antibody was prepared against the major extracellular domain of NET-1 protein by genetic engineering method.Skin tissue specimens were resected from 56 patients with SSCC,50 patients with skin intraepithelial neoplasia(SIN)Ⅰ-Ⅲand 10 normal controls,and all specimens were embeded in paraffin.Immunohistochemistry SP method was used to detect the NET-1 protein expression in these specimens.Results Immunohistochemically,NET-1 protein was clearly located in cell membrane and/or cytoplasm with a weak or absent nonspecific background.The positive rates of NET-1 expression were higher in specimens of SIN Ⅲ and SSCC than in those of SINⅠand SINⅡ(93.75% and 96.43% vs 44.22%,both P<0.01).Significant difference was found in the positive rates of NET-1 expression among the specimens with different expression intensity of Ki67,with different tumor infiltration depth,at different TNM stage,and those collected from different histological types of SSCC(spindle-cell SSCC,verrucous SSCC and general SSCC).Furthermore,the expression intensity of NET-1 was positively correlated with that of Ki67,tumor infiltration depth and TNM stage. Conclusions The designed NET-1 antibody is well located in paraffin-embeded SSCC specimens,and might be a novel,complementary tissue marker for diagnosis of SSCC.

Key words: Carcinoma,squamous cell, Carcinoma in situ, NET-1 antibody