Cathepsin D activity in nasal polyps

ObjectivesThe aim of the study was to assess the activity of cathepsin D in polyps removed during first-time FESS surgery and in recurrent polyps removed during successive FESS surgeries.Design and MethodsThe study examined 24 polyps: 11 polyps were removed during first-time surgical procedures (termed primary polyps in the study), and 13 recurrent polyps were removed in successive FESS surgeries (termed polyps after re-polypectomy in the study). The activity of cathepsin D was determined by measuring the tyrosine released from denatured hemoglobin.ResultThe average cathepsin D activity in polyps after re-polypectomy was 74% higher than the average activity in primary polyps, whereas the difference between the maximum and the minimum cathepsin D activities in polyps after re-polypectomy was twofold greater than the respective difference in primary polyps.ConclusionDifferences in cathepsin activity and the protein content, likely to be significant in the process of polyp recurrence, were observed in both groups of polyps.