Abstract: Objective To investigate the expression and significance of Smad 7,Smurf 1 and Smurf 2 in basal cell carcinoma and squamous cell carcinoma.Methods Biopsy specimens were resected from 14 patients with basal cell carcinoma,19 patients with squamous cell carcinoma and 30 normal controls.Quantitative real-time PCR and immunohistochemical techniques were utilized to assess the expression of Smad 7, Smurf 1 and Smurf 2 in these specimens.Results The gray scale for staining of Smad 7,Smurf 1 and Smurf 2 was 166.61±7.11,166.08±8.71,and 166.25±8.15 respectively in basal cell carcinoma,161.66±5.52,166.84±9.27,and 169.98±9.48 respectively in squamous cell carcinoma.The expression levels of Smad 7,Smurf 1 and Smurf 2 were all significantly increased in basal cell carcinoma and squamous cell carcinoma in comparison with normal controls.Conclusions The over-expression of Smad 7,Smurf 1 and Smurf 2 may interfere with transforming growth factor β signaling transduction pathway through several links,therefore prevent the inhibitory effect of transforming growth factor β on epidermal proliferation,and accelerate the abnormal proliferation in above epidermal tumors.

Key words: Carcinoma,basal cell, Carcinoma,squamous cell, Smad 7, Smurf 1, Smurf2, Transforming growth factor beta, Signal transduction