Role of Granulocyte-Macrophage Colony-Stimulating Factor in Acute Myeloid Leukemia/Myelodysplastic Syndromes

PURPOSE: Granulocyte-macrophage colony-stimulating factor (GM-CSF) cytokine stimulates growth, differentiation, and function of myeloid progenitors. We aimed to study the role of GM-CSF gene expression, its protein, and antibodies in patients with acute myeloid leukemia/myelodysplastic syndromes (AML/MDS) and their correlation to disease behavior and treatment outcome. The study included 50 Egyptian patients with AML/MDS in addition to 20 healthy volunteers as control subjects. PATIENTS AND METHODS: Assessment of GM-CSF gene expression was performed by quantitative real-time polymerase chain reaction. GM-CSF proteins and antibodies were assessed by enzyme-linked immunosorbent assay. RESULTS: There was significant decrease in GM-CSF gene expression (P = .008), increase in serum level of GM-CSF protein (P = .0001), and increase in anti–GM-CSF antibodies (P = .001) in patients with AML/MDS compared with healthy control subjects. In addition, there was a significant negative correlation between serum levels of GM-CSF protein and initial peripheral blood blasts, percentage as well as response to therapy. CONCLUSION: Any alteration in GM-CSF gene expression could have implications in leukemogenesis. In addition, GM-CSF protein serum levels could be used to predict outcome of therapy. GM-CSF antibodies may also play a role in the pathogenesis of AML/MDS. The use of these GM-CSF parameters for disease monitoring and as markers of disease activity needs further research.