Prognostic significance of cytoplasmic macrophage migration inhibitory factor expression in patients with squamous cell carcinoma of the head and neck treated with concurrent chemoradiotherapy

The macrophage migration inhibitory factor (MIF) is known to be a proinflammatory cytokine as well as a tumor growth regulator. Although the positive and negative effects of the MIF on tumor cell growth have been reported, the exact role of the MIF in tumorigenesis remains ambiguous. We examined the expression of the MIF protein in tumor specimens obtained from 50 head and neck squamous cell carcinoma (HNSCC) patients treated with concurrent chemoradiotherapy (carboplatin, 100 mg/m(2)), 4-7 times every week; a total radiation therapy dose of 65-75 Gy over 6.5-7.5 weeks, and determined whether the MIF level is related to clinical outcomes of these patients. Immunostaining with an MIF specific antibody was performed in formalin-fixed, paraffin-embedded specimens. The MIF protein was expressed to various extent in the tumor tissue specimens from the HNSCC patients. Prognostic analysis using the Kaplan-Meier method with regard to the MIF expression revealed that the patients with the MIF-negative tumors had a worse prognosis when compared to those with the MIF expression. The results of this study suggest that the intratumoral MIF expression has a prognostic value in HNSCC patients administered concurrent chemoradiotherapy.