p53, p21 and p27 protein expression in head and neck cancer and their prognostic value

Histological specimens from 62 laryngeal and 31 oral carcinomas were immuno histochemically assessed for p53, p21 and p27 proteins; cases with > 10% la belled nuclei were considered as positive, p21 showed higher expression in patients > 65-years-old (P = 0.04), in chemotherapy responders (P = 0.02), and in stage III patients with longer overall survival (P = 0.02), represen ting the only independent prognostic factor in the multivariate analysis. I n addition, stage III patients with p53/p21+ showed the longest survival wh ereas those with p53+/p21- tumors showed the shortest overall survival (P = 0.02). A significant influence on the survival of stage III patients was a lso found for the combinations of p21 and p27 proteins with p21+/p27- impar ting the best and p21-/p27+ the worst prognosis (P = 0.04). p27 expression was significantly related to ol al cancel specimens (P = 0.04) and to moder ate and high tumor grade (P = 0.01). p53 expression was not significantly r elated to any of the examined clinicopathological characteristics. Our find ings indicated that, by functionally promoting apoptosis, p21 seems To play a key role in the successful response to chemotherapy and may be considere d as a predictive factor of a better prognosis in stage III patients with h ead and neck cancers.