Background & objective: Smad proteins are downstream signal proteins of the transforming growth factor-beta (TGF-beta) superfamily, which are intimately related to the genesis of many human carcinomas. Human papillomavirus (HPV) is an important carcinogenic agent of cervical cancer. However, their relationship in the genesis of cervical cancer is unclear. This study was to detect the expression of Smad2/3 and HPV16 E7 protein in different cervical lesions, and to explore their possible roles in tumor genesis and progression.
Methods: The expression of Smad2/3 and HPV16 E7 in 20 specimens of chronic cervicitis, 30 specimens of cervical intraepithelial neoplasia (CIN), and 30 specimens of cervical cancer was detected by SP immunohistochemistry.
Results: The positive rates of Smad2/3 were significantly lower in cervicitis and CIN than in cervical cancer (50.0% and 73.3% vs. 93.3%, P<0.05), and significantly lower in cervicitis than in CINIII(P<0.05). The positive rates of HPV16 E7 were 60.0% in cervicitis, 66.7% in CIN, and 83.3% in cervical cancer (P>0.05). The expression of Smad2/3 in cervical cancer had no correlation to clinical stage, pathologic classification, histological grade, and lymph node involvement(P>0.05). Smad2/3 expression was positively correlated to HPV16 E7 infection (r=0.271, P=0.015, R-Spearman).
Conclusions: Overexpression of Smad2/3 may be involved in the genesis of cervical cancer. It is closely correlated to HPV infection in cervical carcinoma.