Taziki MH, et al. - The current study was interested in exploring the expression of toll-like receptor 4 (TLR4), TLR9, high-mobility group box 1 protein (HMGB1), and pNFκ-B p65 in paraffin-embedded blocks of patients with chronic rhinosinusitis (CRS) with nasal polyps vs those of the control group. For this investigation, 26 formalin-fixed, paraffin-embedded samples from patients with confirmed CRS and 26 patients undergoing septoplasty due to anatomic variations and no other inflammatory nasal diseases as the control group were evaluated. Real-time polymerase chain reaction demonstrated that the expression level of HMGB1 messenger RNA was significantly increased in the tissues of CRS patients vs controls. In the paranasal sinus mucosa of patients with CRS, both HMGB1 and TLR4 are increased. These findings indicate a possible contribution to CRS pathophysiology by HMGB1 and its internal receptor (TLR4).