p21 Waf1/CIP1 is a poor diagnostic and prognostic marker for OSCC although its expression increases in patients with N1 regional metastasis

Abstract

Objectives:

Downregulation of p21^Waf1/CIP1 (a cyclin-dependent kinase inhibitor) has been reported for mouth cancer. The goal of this article is to quantitatively report expression of p21^Waf1/CIP1 and evaluate its relationship with the clinical and prognostic factors.

Materials and Methods:

this is a retrospective study of 68 patients diagnosed with OSCC. We constructed a tissue microarray to develop an immunohistochemical assessment of p21^Waf1/CIP1 expression. A multivariate analysis using a forward-selection stepwise regression model (Cox, 1972) for predicting survival was performed.

Results:

The quantitative expression of p21^Waf1/CIP1 showed a statistically significant relationship with the risk of lymph node metastasis, showing a higher expression in patients with homolateral single nodes of less than 3 cm (N1) (X²=6.58; p< 0.05). We found no statistically significant relationship with any other clinical or pathological parameters. The Cox univariate regression analysis verifies that the effect of the value of p21^Waf1/CIP1 on survival was not statistically significant (p=0.6). The best predictive multivariate Cox analysis included the covariates: recurrence, p21^Waf1/CIP1, gender, stage, and dysplasia in the adjacent margin. All these variables showed a statistically significant relationship with survival, except p^21Waf1/CIP1.

Conclusion:

quantitative determination of p21^Waf1/CIP1 standardizes and facilitates its analysis. Although its expression increases in patients with N1 regional metastasis, the loss of p21^Waf1/CIP1 does not seem to have any relationship with the clinical and pathological variables of the tumors.