Apoptosis and apoptotic-related factors in mucoepidermoid carcinoma of the oral minor salivary glands

The oncoproteins Bcl‐2 and Bax, the tumor suppressor gene product p53, TUNEL (TdT [terminal deoxynucleotidyl transferase] dUTP nick end‐labeling) and the cell‐cycle antigen Ki‐67 were studied in 71 cases of mucoepidermoid carcinoma originating in the oral minor salivary glands. Grade I tumors had higher expression of Bcl‐2 than Grade II and III tumors (χ2 test, 0.01 < P < 0.025) and the Bcl‐2‐positive group had a higher survival rate than the Bcl‐2‐negative group (generalized Wilcoxon, P = 0.00051). Patients with strong TUNEL positivity had a higher survival rate than those with either weak positivity or negativity (generalized Wilcoxon, P = 0.047). The expression of p53 and TUNEL had a positive correlation (P = 0.0315). Grade II and III tumors had a higher frequency of positive Ki‐67 expression than Grade I tumors (χ2 test, 0.01 < P < 0.025) and patients with Ki‐67‐negative tumors had better survival than patients with Ki‐67‐positive tumors (generalized Wilcoxon, P = 0.000099). This study showed that Bcl‐2 proteins, p53 protein, TUNEL and Ki‐67 are potentially useful prognostic markers for survival in patients with mucoepidermoid carcinoma of the oral minor salivary glands.