Expression And Effects Of TGF-β₁ And Its Intracellular Signaling Molecule Smad₄, Smad₇ In Human Glioma

Objective To investigate the expression of TGF-β₁ and its intracellular signaling molecules Smad₄, Smad₇ in human glioma.Methods The expression levels of Smad₄ and Smad₇ in 30 cases of human glioma and 8 cases of normal brain tissue specimen were detected by immunohistochemical technics.Results In normal brain tissue, grade â…  â…¡ and â…¢^â…£ astrocytoma, the positive expression level of TGF-pi was 5.90±3.78, 14.21±4.89, 36.02±12.33 respectively, and the level of Smad₄ was 44.80±16.19, 25.81±9.48, 6.73±3.71 respectively, and the level of Smad₇ was 6.69±3.86, 18.22±7.84, 41.95±17.27 respectively. The difference was significant (P<0.05) among normal brain tissue, group â…  â…¡ and â…¢-â…£. The expression of Smad₄ was lower in glioma than that in normal tissue. However, the expression of Smad₇ and TGF--β₁ was positively correlated with the tumor grade. There was a positive correlation between TGF--β₁ and Smad₇, while a negative correlation between TGF-pi and Smad₄.Conclusion These findings suggested that TGF--β₁ and Smad₇ play an important role during the malignant behavior of glioma. Smad₄ could be a candidate tumor suppressor gene of glioma.