I Bosek, R Kuczerowski, T MiÅek, A Sulich, B Kaleta, M Kniotek and P PiÄ tkiewicz1
Introduction and objectives: Multiple studies suggest a common coexistence of type 2 diabetes mellitus (T2DM) and cancer, especially colorectal cancer (CC). One of the most important mechanism that may have an impact on the increased incidence of cancer in diabetes is deregulation in the immune system. Interferon gamma (IFNγ), a cytokine critical for anti-tumor immunity, enhances cytotoxic activity of Tc lymphocytes, natural killer (NK) cells, activates macrophages, affects the apoptosis and induces the production of other cytokines such as IL-2, IL-6. The aim of this study was to evaluate the concentration of IFNγ in patients with T2DM with accompanying colorectal cancer compared to patients with T2DM or colorectal cancer separately. Materials and methods: This study was performed in Department of Internal Diseases, Diabetology and Endocrinology and Department of General and Vascular Surgery, Medical University of Warsaw, and the Clinic of Metabolic Diseases and Gastroenterology Institute of Food and Nutrition in Warsaw. In this study 79 patients were enrolled. They have been divided into 4 groups: group 1 (23 subjects) with T2DM, group 2 (23 subjects) with CC, group 3 (10 subjects) – with CC and T2DM, and group 4 (23 subjects) without T2DM or CC. All patients had a colonoscopy performed. In the case of cancer there was done histopathological study. Laboratory measurements included fasting glucose, insulin, C-peptide, HbA1c, lipidogram. The concentration of IFNγ in serum was determined with the immunoenzymatic (ELISA) method. Results: IFNγ level in patients from group 1 (T2DM) was 3.13 ± 0.92 pg/ml, group 2 (CC) –2.73 ± 0.91 pg/ ml, group 3 (T2DM and CC) – 2.46 ± 0.98 pg/ml and group 4 (control) –5.02 ± 1.43 pg/ml; p < 0.05. There was no statistically significant difference in the concentration of IFNγ in patients with T2DM and CC compared to other subjects. However, it has been demonstrated that level of IFNγ in the control group and the group of patients with T2DM without CC was higher than in the other two groups. There was no statistically significant difference between the groups in levels of insulin, C-peptide and HOMA-IR. Conclusions: The concentration of IFNγ did not differ significantly between all studied groups of patients. A better understanding of the role of IFNγ in T2DM and CC will contribute to identification of risk factors, more precise diagnosis and treatment of both diseases. Future studies are needed to confirm the validity of these observations.