Marsupialization inhibits interleukin‐1α expression and epithelial cell proliferation in odontogenic keratocysts

AbstractBackground:   Marsupialization results in the reduction of odontogenic cyst size. Interleukin‐1α (IL‐1α) is thought to play a crucial role for the expansion of odontogenic keratocysts. The aim of this study was to investigate the effects of marsupialization on the expression of IL‐1α and on the proliferating activity of a lining epithelium in odontogenic keratocysts.Methods:   The concentrations of IL‐1α, interleukin‐6 (IL‐6) and tumor necrosis factor‐α (TNF‐α) in the intracystic fluids of odontogenic keratocysts were measured by the enzyme‐linked immunosorbent assay (ELISA). The expression of IL‐1α mRNA in odontogenic keratocysts was measured before and after marsupialization by in situ hybridization. The expression of IL‐1α and epithelial cell‐proliferating activities in odontogenic keratocysts were also measured by immunohistochemistry using antibodies for human IL‐1α and Ki‐67 antigen, respectively.Results:   The intracystic fluid levels of IL‐1α were significantly higher than those of IL‐6 and TNF‐α in odontogenic keratocysts. In situ hybridization and immunohistochemistry showed that strong expression of IL‐1α mRNA and protein was mainly detected in the epithelial cells of odontogenic keratocysts. After marsupialization, the signal intensities for IL‐1α mRNA and protein were significantly decreased. In addition, the Ki‐67 labeling index of the epithelial cells was decreased proportionally with the grade of IL‐1α mRNA expression after the marsupialization.Conclusion:   Our findings suggest that marsupialization may reduce the size of odontogenic keratocyst by inhibiting IL‐1α expression and the epithelial cell proliferation.