metallothionein and Nasal-Polyps

The expression of metallothionein (MT) is involved in acquiring resistance to immune-mediated apoptosis; it is also a negative regulator of the immune response. Nasal polyps are typified by a resistance to immune-mediated apoptosis as well as by excessive immune cell infiltration. RCAS1 (receptor-binding cancer antigen expressed on SiSo cells) is a membrane protein capable of inducing the apoptosis of CTLs and NK cells. The aim of the present study has been to explore the expression of metallothionein with respect to immune cell presence and immune cell activity. In our study, we identified immune cells using CD4 and CD68 antigen expression and evaluated their activity using CD25 antigen expression. We then analyzed metallothionein, RCAS1, CD25, CD4, and CD68 in a sampling of 50 nasal polyps using the immunohistochemistry method. We were able to divide the nasal polyps into three main groups according to their predominant immune cell infiltration: eosinophilic nasal polyps (21 cases), lymphocytic nasal polyps (17 cases), and neutrophilic nasal polyps (12 cases).. In the present study, statistically significant differences between the MT expression in the epithelium and that in the stroma of the nasal polyps along with the accompanying alterations in activation markers on immune cells were found and the number of macrophages in both the eosinophilic and the lymphocytic nasal polyps was assessed. RCAS1-expressing macrophages were found only in the eosinophilic nasal polyps.. MT expression seems to favor the survival of nasal polyp epithelial cells in the adjacent area of increasingly cytotoxic immune activity. RCAS1-expressing macrophages seem to participate in creating the immune suppressive microenvironment and so help to sustain local inflammation.

Topics: Antigens, CD; Antigens, Neoplasm; Apoptosis; Cell Movement; Chronic Disease; Cytotoxicity, Immunologic; Eosinophils; Humans; Lymphocytes; Metallothionein; Nasal Mucosa; Nasal Polyps; Neutrophils; Rhinitis; Sinusitis; Stromal Cells

Acquiring the immune-mediated apoptosis and the ability to regulate the cytotoxic immune response are the main phenomena playing fundamental roles in such situations as neoplasm survival and creation of immune tolerance during pregnancy. The aim of this study was to investigate these phenomena through the evaluation of metallothionein and RCAS1 proteins in neoplasm and its healthy environment (clear surgical margin), physiological conditions in placenta and its environment (decidua) and the comparison to non-neoplasmatic lesions originating from the environment (nasal polyps, endometriosis). We have shown that the growth of RCAS1 expression was simultaneous to the infiltration of activated immunological cells of tumor environment as well as decidua. The activity of immunological cells was in our study selectively suppressed. Metallothionein expression growth was also observed in healthy tumors stroma and in decidua probably in response to the growing cytotoxic activity and tumor spread. Alterations in RCAS1 and Metallothionein expression seem to be associated with local immune dysfunction in nasal polyps and endometriosis. In conclusion, the ability to compensate the growing cytotoxic immune response is physiologically observed in decidua, the lost of this ability in tumor environment might participate in the development of tumor spread.

Topics: Antigens, Neoplasm; Apoptosis; Decidua; Endometriosis; Female; Humans; Immune Tolerance; Immunity, Cellular; Lymphatic Metastasis; Menstrual Cycle; Metallothionein; Nasal Polyps; Neoplasms; Placenta