The analysis of RCAS1 and DFF-45 expression in nasal polyps with respect to immune cells infiltration

The higher RCAS1 level was identified in lymphocytic nasal polyps, the medium one in eosinophilic while the lowest was identified in neutrophilic. DFF-45 expression was higher in eosinophilic than in neutrophilic and lymphocytic nasal polyps.The changes in DFF-45 level in nasal polyps might indicate a different resistance to apoptosis mediated by immune cells. The alterations in RCAS1 expression indicate that nasal polyps have the ability to regulate the cytotoxic immune response.The breaking of resistance to immune mediated apoptosis in nasal polyps might have a new therapeutic impact.Nasal polyp constitutes a benign growth process in the nasal and sinus mucosa which is mainly located in the middle meatus and never in the inferior meatus. The etiology of nasal polyps, which is a common clinical condition, is not well understood. Infections, allergy and immunological factors are considered.Histopathologically polyps surface is covered by a ciliated pseudostratified epithelium and the subepithelial area is characterized by an eosinophilic inflammation in more than 80% of cases. The density of goblet cells in nasal polyps is much lower than in the normal nasal mucosa. The glands of nasal polyps are long, tubular, of varying shape, size and type, and their density is more than 10 times lower than in nasal mucosa [1-3].Receptor-binding cancer antigen expressed on SiSo cells (RCAS1) is a protein which has been demonstrated in various human cancer cells responsible for tumour escape from host immunological surveillance. RCAS1 is not only the marker of cancer process, but its expression has also been observed in physiological conditions and the development of non-neoplastic tumours [4-11]. It has been demonstrated in the bone marrow, the endometrium, the decidua, the placenta, Waldeyer's ring and immune mediated diseases. RCAS1 seems to be responsible for the regulation of cytotoxic cells activity [10-18]. Within Waldeyer's ring RCAS1 has been expressed by reticular epithe