Expression and Effects of Smad^₄ and Smad₇ in Human Glioma

Abstract :Objective 　To investigate the expression of Smad₄ and Smad₇ proteins, which are int racellular signaling molecules of transforming growth factor-βfamily 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 immunohist-ochemical technics. Results 　In normal brain tissue, group Ⅰ, Ⅱand Ⅲ, Ⅳ, the positive expression levels of Smad₄ was 44. 80 ±16. 19, 25. 81 ±9. 48, 6. 73 ±3. 71 respectively, and Smad₇ was 6. 69 ±3. 86, 18. 22 ±7. 84, 41. 95 ±17. 27 respectively. The difference were significant ( P <0. 05) . The expression of Smad₄was lower in glioma than normal tissue. However, the expression of Smad₇ was positively correlated with the tumor grade. Smad₄ and Smad₇ were negative correlation ( r =-0. 82) . Conclusion 　These finding suggested that Smad₇ play an important role during the malignant behaviors of glioma. Smad₄ could be a good tumor suppressor gene of glioma.