Discrimination of ameloblastomas from odontogenic keratocysts by cytokine levels and gelatinase species of the intracystic fluids

In the present study, we measured the levels of the cytokines and gelatinas e species in the fluids of ameloblastomas and odontogenic keratocysts, and showed that ameloblastomas can be distinguished from odontogenic keratocyst s by the use of these biochemical data. We found that interleukin (IL)-1 al pha and IL-1 beta levels in the intracystic fluids of ameloblastomas were s ignificantly lower than those in the fluids of odontogenic keratocysts, whi le IL-6 levels in the fluids of ameloblastomas were significantly higher th an those in the fluids of odontogenic keratocysts. On the other hand, no si gnificant differences in tumor necrosis factor (TNF)alpha levels of the flu ids were detected between ameloblastomas and odontogenic keratocysts. An im munohistochemical study revealed that the staining intensity of IL-1 alpha, IL-1 beta and TNF-alpha in the tumor cells of ameloblastomas was significa ntly weaker than that in the epithelial cells of odontogenic keratocysts, w hile the staining intensity of IL-6 in the tumor cells was significantly st ronger than that in the epithelial cells of odontogenic keratocysts. Gelati n zymography of the fluids showed that only a small amount of pro-MMP-9 was detected in ameloblastomas, while both pro-MMP-9 and the active form of MM P-9 were detected in 8 of 10 cases of odontogenic keratocysts. Thus, amelob lastomas can be distinguished from odontogenic keratocysts by measuring IL- 1 alpha and IL-6 levels, and gelatinase species in the fluids.