Role of p38 MAPK Pathway in Induction of iNOS Expression in Neutrophils and Peripheral Blood Mononuclear Cells in Patients With Squamous Cell Carcinoma of the Oral Cavity

Ratajczak-Wrona, Wioletta; Jablonska, Ewa; Marcinczyk, Magdalena; Grabowska, Zyta; Piotrowski, Leszek

doi:10.1016/j.joms.2009.04.030

« Previous Next »Journal of Oral and Maxillofacial Surgery
Volume 67, Issue 11 , Pages 2354-2363, November 2009

Role of p38 MAPK Pathway in Induction of iNOS Expression in Neutrophils and Peripheral Blood Mononuclear Cells in Patients With Squamous Cell Carcinoma of the Oral Cavity

Wioletta Ratajczak-Wrona, PhD
- Lecturer, Department of Immunology, Medical University of Bialystok, Bialystok, Poland
- Address correspondence and reprint requests to Dr Ratajczak-Wrona: Department of Immunology, Medical University of Bialystok, Waszyngtona 15A, Bialystok 15-269 Poland
Ewa Jablonska, DSc
- Professor of Immunology, Department of Immunology, Medical University of Bialystok, Bialystok, Poland
Magdalena Marcinczyk, PhD
- Assistant, Department of Immunology, Medical University of Bialystok, Bialystok, Poland
Zyta Grabowska, DDS, DSc
- Professor of Stomatology, Department of Oral and Maxillofacial Surgery, Medical University of Bialystok, Bialystok, Poland
Leszek Piotrowski, DDS
- Assistant, Department of Oral and Maxillofacial Surgery, Medical University of Bialystok, Bialystok, Poland

Purpose

The aim of the present study was to assess the role of the p38 mitogen-activated protein kinase (MAPK) pathway in the induction of inducible nitric oxide synthase (iNOS) expression and the production of NO by neutrophils (polymorphonuclear neutrophils [PMNs]) and peripheral blood mononuclear cells (PBMCs) in patients with squamous cell carcinoma (SCC) of the oral cavity.

Patients and Methods

PMNs and PBMCs were isolated from 24 patients with SCC. The expression of iNOS and phospho-p38 MAPK was estimated by Western blotting. Total NO was measured in the cell supernatants and serum using the Griess method. The generation of superoxide anion radicals by the cells was estimated using the cytochrome-c reduction test. The cyclic guanosine monophosphate level in the cell supernatants and plasma was assessed using an enzyme-linked immunosorbent assay kit, and the concentrations of malonyldialdehyde in serum were assessed using a thiobarbituric acid method.

Results

The results of the present study of patients with stage II and III disease showed lowered expression of iNOS and phospho-p38 MAPK in PMNs and PBMCs. Moreover, in these patients, a lower production of NO by PMNs and PBMCs was observed. However, the opposite relationship was observed between the expression of phospho-p38 MAPK and iNOS in the leukocytes of patients with stage IV disease. The concentration of total NO in the PMN and PBMC supernatants of patients with advanced disease stages did not differ from that of the control group. In all the patients with SCC, a lowered ability of neutrophils to generate superoxide anion radicals and an increased production of cyclic guanosine monophosphate by PMNs and PBMCs was confirmed. Furthermore, a greater concentration of cyclic guanosine monophosphate was found in the plasma and total NO in the serum of patients with stage IV disease compared with the levels in the control group. A greater concentration of malonyldialdehyde in the serum of all patients compared with that in the control group was also observed.

Conclusions

Our results indicate that in the leukocytes of patients with stage II and III SCC, the p38 MAPK pathway performs an essential role in the induction of iNOS expression, and the process of lipid peroxidation is not dependent on NO. In contrast, in patients with advanced-stage SCC, iNOS expression did not seem to be linked with the p38 MAPK pathway, and NO directly influenced the process of lipid peroxidation.