The Role of Host Immune Response and Apoptosis in Patients with Laryngeal Squamous Cell Carcinoma

Abstract

Purpose: To determine whether the combined use of markers of host immune response (HLA-DR) and apoptosis (bax and bcl-2) can predict prognosis in laryngeal carcinoma patients. Procedures: Immunohistochemical staining for HLA-DR, bax and bcl-2 proteins was investigated retrospectively in 37 patients with laryngeal squamous cell carcinoma. Seven healthy adult males were used as the control group. Results: HLA-DR antigen expression was detected in the tumor cells of 18 patients (48.6%). Another 18 patients (48.6%) expressed HLA-DR antigen in the peritumoral inflammatory infiltrate, while bax and bcl-2 protein expressions were detected in 17 (45.9%) and 9 (24.3%) patients, respectively. None of the controls expressed any of the proteins studied. bcl-2 and HLA-DR protein expressions of the tumor infiltrate were statistically significant independent prognostic factors suggesting improved survival (p = 0.0272 and p = 0.0285, respectively). bax+/bcl-2– patients demonstrated an unfavorable clinical outcome (p = 0.0298), followed by a significantly increased mean HLA-DR antigen expression observed both in the tumor and the stroma cells (p = 0.024 and p = 0.045, respectively). Conclusions: bcl-2 and HLA-DR proteins independently predict a dismal prognosis among laryngeal carcinoma patients. The bax+/bcl-2– protein coexpression pattern correlates with elevated immunohistochemical expression of HLA-DR antigen both by tumor and peritumoral stromal cells. Message: bcl-2 and HLA-DR are significant prognostic markers in laryngeal carcinoma patients. Further prospective investigation is required to validate our findings.