The Research Of The Expression Of Smad4 And Smad7 In Oral Squamous Cell Carcinoma

BMPs (except BMP-1) belong to transforming growth factor-β(TGF-β) superfamily, initially, they were recognized as factors that can induce bone and cartilage formation in vivo, now researchs suggest that they are involved in regulating a variety of biological processes like cell proliferation, differentiation and apoptosis, BMPs and their receptors are expressed in many tumor tissues, BMPs may play an important role in tumor occurrence and development. There are at least two BMP signaling pathways:the Smad pathway; the MAPK pathway, the Smad protein family is a recent discovery of new intracellular signaling proteins which are directly involved in the signal transduction of bone morphogenetic proteins and other members, but few studies about the role of Smad4 and Smad7, in this study, SP immunohistochemical method was used to detect the expression of Smad4 and Smad7, and in comparison with normal tissue, changes were observed, the role of BMPs on the growth and development of oral squamous cell carcinoma was found, so we can know their mechanisms and to search for an effective gene therapy for oral squamous cell carcinoma.ObjectiveChanges were observed between Smad4 and Smad7 in oral squamous cell carcinoma and adjacent normal tissue, the role of Smad4 and Smad7 on the growth and development of oral squamous cell carcinoma was found.MethodsSP immunohistochemical method was used to detect the expression of Smad4 and Smad7 in oral squamous cell carcinoma and adjacent normal tissue, and for statistical analysis.Results1.The positive expression rate of Smad4 protein in normal tissues is 69.44%, the positive expression rate of Smad4 protein in oral squamous cell carcinoma is 45.83%(Table 1), P<0.05, there are significant differences, and the positive expression rate lower with the degree of differentiation decreased(Figure 5); the positive expression with lymph node metastasis rate is 22.50%, the positive expression without lymph node metastasis is 65.63%(Table 3, Figure 9), P<0.05, there are significant differences.2. The positive expression rate of Smad7 protein in normal tissues is 19.44%, the positive expression rate of Smad7 protein in oral squamous cell carcinoma is 83.33%(Table2), P<0.05, there are significant differences, and the positive expression rate higher with the degree of differentiation decreased(Figure 8); the positive expression with lymph node metastasis rate is 92.50%, the positive expression without lymph node metastasis is 68.75%(Table 4, Figure 10), P<0.05, there are significant differences.Conclusions1. The expression of Smad4 in cancer tissues is significantly reduced, and the expression lower with the degree of differentiation decreased, the expression of Smad4 with lymph node metastasis rate is lower than the expression without lymph node metastasis.2. The expression of Smad7 in cancer tissues is significantly increased, and the expression higher with the degree of differentiation decreased, the expression of Smad7 with lymph node metastasis rate is higher than the expression without lymph node metastasis.3. Loss of expression of Smad4 may contribute to the development and metastasis of oral squamous cell carcinoma; overexpression of Smad7 may promote the develop- ment and metastasis of oral squamous cell carcinoma; the inhibition of BMP/Smads signaling pathway may result in the occurrence and development of oral squamous cell carcinoma.