CSF2 and neoplasm: However, our results were not consistent with some reports of DNA vaccine studies in which GM-CSF acted as the adjuvant and could enhance immune responses via several mechanisms, including the activation of granulocytes, macrophages and natural killer T cells and the promotion of the local recruitment and maturation of DCs, which likely led to the improvement of tumor antigen presentation to T lymphocytes [32], [33], [34].