Evaluation of Insulin-like Growth Factor-1 and Insulin-like Growth Factor Binding Protein-3 Expression Levels in Patients with Chronic Lymphocytic Leukemia

Abstract

Objective: Chronic lymphocytic leukemia (CLL) is a disease of nonproliferating and mature-appearing B lymphocytes. Insulin-like growth factor-1 (IGF-1) is a small peptide hormone and has mitogenic and antiapoptotic effects, and insulin-like growth factor binding protein-3 (IGFBP-3) has antiproliferative effects on cells. In this study, we investigated plasma levels of both IGF-1 and IGFBP-3 in patients with CLL compared with controls, and we compared these plasma levels according to prognostic factors. Materials and Methods: Patients with newly diagnosed CLL who were being followed at the Haseki Training and Research Hospital, İstanbul, Turkey, and volunteers were included in this study. Patients were stratified according to the Rai staging system. Statistical analysis was conducted using SPSS 17.0 for Windows. Results: Forty-three patients [16 women (37%) and 27 men (63%)] were enrolled in this study. Twenty-one volunteers (11 women, 10 men) were included in the control group. The median age of the patients was 65+-9 years (range: 18-63 years), and subjects in the control group were 68+-8 years old (range: 18-63 years). Even though the plasma levels of IGF-1 were higher and those of IGFBP-3 were lower and the ratio of IGF-I/IGFBP-3 was higher in comparison with the control group, these differences were not statistically significant (p>0.05). In the study group, IGF-1 levels appeared to be increased in parallel to more advanced Rai stages. There were no significant differences between the other groups (p=0.105). Conclusion: Plasma IGF-I levels were found higher in patients than in the control group and plasma IGFBP-3 levels were lower; however, neither result was statistically significant. Plasma IGF level increment was observed in concordance with Rai staging. These results prompted us to think that plasma IGF-1 levels in CLL patients are correlated with tumor burden and Rai staging and therefore could be a valuable prognostic factor. Further comprehensive studies are required to support our results.

Keywords

• chronic lymphocytic leukemia
• insulin-like growth factor-1
• insulin-like growth factor binding protein-