Expression Of TGF β Receptor Ⅰ And Ⅱ, Smad7, Smurf1 And Smurf2 In Seborrheic Keratosis, Basal Cell Carcinoma And Squamous Cell Carcinoma

Background: Transforming growth factorβ(TGFβ) plays an important role in maintaining the homeostasis of epithelial tissue. Smads mediate and regulate intracellular TGFβsignaling from the membrane receptors to nuclei. Among these Smads, Smad7, Smad ubiquitination regulatory factor 1 and 2 (Smurf1 and Smurf2) exert a variety of catastaltic functions to regulate TGFβsignal pathway.Seborrheic keratosis, basal cell carcinoma and squamous cell carcinoma are clinically common epidermal tumors associated with skin aging and ultraviolet radiation. The blockade of TGFβ/Smad signal pathway is involved in photoaging, ultraviolet radiation and tumorigenesis in epithelial tumors. Whether the expressions of TGFβRI and TGFβRII are changed and associated with the expressions of Smad7 and Smurfs in seborrheic keratosis, basal cell carcinoma and squamous cell carcinoma remain unknown.Objective: To investigate the expressions of TGFβRI, TGFβRII, Smad7, Smurf1 and Smurf2 in seborrheic keratosis, basal cell carcinoma and squamous cell carcinoma, for an insight into the mechanism of aberrant TGFβsignaling and tumorous hyperplasia in the epidermal tumors mentioned above.Method: Reverse transcription (RT)-Realtime polymerase chain reaction (PCR) and EliVisionTM plus immunohistochemical techniques were utilized to detect the expresions of TGFβRI, TGFβRII, Smad7, Smurf1 and Smurf2 mRNA and protein in seborrheic keratosis, basal cell carcinoma, squamous cell carcinoma and control normal skin specimens.Results: RT-PCR and immunohistochemistry revealed that the expressions of TGFβRI and TGFβRII mRNA and protein were significantly down-regulated, and the expressions of Smad7, Smurf1 and Smurf2 mRNA and protein was significantly up-regulated in seborrheic keratosis, basal cell carcinoma and squamous cell carcinoma compared with control normal skin specimens.