Estudo da apoptose em cultura de pólipos nasais eosinofílicos submetidos ao efeito da Mitomicina C

Abstract

The etiopathogenesis of nasal polyps still is to be clarified. Eosinophils are possibly the most important inflammatory cells in the pathogenesis of rhinossinusitis with nasal polyposis. The treatment of nasal polyps involves an important role for apoptosis in the removal of inflammatory cells and resolution of inflammatory processes. Mitomycin C(MMC) is a chemotherapeutic agent and has been used in otorhinolaryngology to reduce stenosis and scar formation after surgery. The aim of this study was to evaluate the MMC action in apoptotic index (AI) in nasal polyps from eosinophilic nasal poliposis patients. This is a comparative and auto-matched experimental study with 15 in vitro fragment biopsies cultures from nasal polyps with eosinophilic infiltration percentage equal or superior to 40%. Each fragment was divided in two groups. The polyps fragments from the two groups were cultured at 370 C in 5% CO2 was stored for study at zero and twelve hours. The culture from the group test was treated with 400 !g/ml MMC concentration for 5 minutes. The AI was determined by histopathology by staining each cultured specimen with hematoxylin and eosin(HE) and by analysis of apoptotic DNA fragmentation (nick end labeling technic).Comparing the two groups, with and without MMC treatment, there was a statistic significance difference (p<0,001) at 12 hours in AI after MMC treatment. MMC was able to induce apoptosis in eosinophilic nasal polyps. There was no difference between the AI result in histopathology and by analysis of DNA fragmentation.This study showed that mitomycin C acts in nasal polyps by inducing eosinophils apoptosis.