Increased genome instability and oxidative DNA damage and their association with IGF-1 levels in patients with active acromegaly

The objectives of this study were to assess cytokinesis-block micronucleus cytome (CBMN Cyt) assay parameters and also oxidative DNA damage in patients with active acromegaly and controls and to assess the relationship between age, serum insulin-like growth factor 1 (IGF-1) levels, pituitary adenoma diameters, 8-hydroxy-2′-deoxyguanosine (8-OHdG) levels and CBMN Cyt assay parameters in patients with active acromegaly. The study population included 30 patients with active acromegaly and 30 age- and sex-matched healthy controls. CBMN Cyt assay parameters in peripheral blood lymphocytes of patients with active acromegaly and controls were evaluated and plasma 8-OHdG levels were measured. Frequencies of micronucleus (MN), nucleoplasmic bridges (NPBs) and nuclear buds (NBUDs) in lymphocytes of patients with acromegaly were found to be significantly higher than those in controls (p < 0.001, p < 0.001, p < 0.001, respectively). The frequencies of apoptotic and necrotic cells in lymphocytes of patients with acromegaly were found to be significantly higher than those in controls (p < 0.001 and p < 0.001 respectively). No statistically significant differences in the number of cells in metaphase, the number of bi-nucleated cells (M2), the number of tri-nucleated cells (M3), the number of tetra-nucleated cells (M4) and nuclear division index (NDI) values were observed between patients and controls (p > 0.05). Plasma 8-OHdG (ng/ml) levels in patients with acromegaly were found to be significantly higher than those in controls (p < 0.005). MN frequency in the lymphocytes of patients with acromegaly increased with elevated serum IGF-1 levels (p < 0.05), whereas the number of NPBs and the frequency of apoptotic cells decreased with elevated serum IGF-1 levels (p < 0.01 and p < 0.05 respectively). Both the increase in chromosomal/oxidative DNA damage and the positive association between MN frequency and serum IGF-1 levels may predict an increased risk of malignancy in acromegalic patients. Long-term follow-up of patients with acromegaly will be necessary to establish the degree of cancer risk in this population.