Expression of p27, p21(WAF/Cip1), and p16(INK4a) in normal oral epithelium, oral squamous papilloma, and oral squamous cell carcinoma.

AIM To characterize the immunohistochemical expression of p27, p21(WAF/Cip1) and p16(INK4a) in normal oral epithelium, oral squamous papilloma and oral squamous cell carcinoma. MATERIALS AND METHODS Immunohistochemical staining for p27, p21(WAF/Cip1) and p16(INK4a) was evaluated in 32 samples of normal oral squamous epithelium, 30 samples of oral squamous papilloma, and 34 samples of oral squamous cell carcinoma. RESULTS Statistically significant differences (p<0.05) were found in p27 expression when comparing ordinary mucosa and oral squamous papilloma with the oral squamous cell carcinoma samples. Regarding p21(WAF/Cip1) expression, no statistically significant differences (p>0.05) were noticed. In the same way, no significant statistically differences (p>0.05) were observed for p16(INK4a) among groups. CONCLUSION Taken together, these findings indicate that p27 is closely involved in malignant transformation of oral mucosa cells, and may be a reliable biomarker for this purpose.