Overexpression of High-Mobility Motor Box 1 in the Blood and Tissues of Patients with Head and Neck Squamous Cell Carcinoma.

Introduction: Head and neck squamous cell carcinoma (HNSCC) is one of the most common cancers in the world. Extra- and intra-cellular high-mobility motor box 1 (HMGB1) proteins are invovled in the pathogenesis and prognosis of cancer. Regarding this, the present study was conducted with the aim of investigating the expression of HMGB1 protein and mRNA levels in the blood, tumor tissue, and marginal normal tissue of patients with head and neck squamous cell carcinoma (HNSCC) using the quantitative real-time polymerase chain reaction (qRT-PCR) and immunohistochemistry (IHC).

Materials and Methods: This study was performed on 88 patients with HNSCC, who referred to the otorhinolaryngology and oral pathology departments, affiliated to Mashhad University of Medical Sciences, Mashhad, Iran, and a group of healthy subjects (i.e., control group) matched in terms of age and gender. RNA was collected from fresh tumor tissues, marginal tissues, and blood, followed by the implementation of quantitative PCR on the specimens. Furthermore, the expression of HMGB1 in tumor and normal margins was evaluated by means of IHC. The data were analyzed in SPSS software.

Results: According to the results the expression levels of HMGB1 protein and mRNA were significantly higher in the tumor tissue than in the normal margin tissues (P<0.01). In addition, there was a significant correlation between histologic grading and the expression of HMGB1 protein and mRNA in tissues (P<0.05). Furthermore, the receiver operating characteristic curve of the HMGB1 mRNA in tissue was located closer to the theoretical 100% sensitivity.

Conclusion: The findings revealed a higher increase in the levels of mRNA and HMGB1 protein in HNSCC, compared to those in the normal margin tissues. In addition, HMGB1 mRNA showed a significant expression in the tissue and blood of the patients with lymph node involvement.