Relationship between plasma levels of vascular endothelial growth factor and serum levels of interleukin-12 in patients with colorectal cancer

Background: Vascular endothelial growth factor (VEGF) is thought to be the most potent angiogenic factor in the numerous malignant tumors and a progno stic indicator for cancer patients, Interleukin 12 (IL-12) is a heterodimer ic cytokine that has potent anti-tumor and anti-metastatic activities. Rece ntly, it has been suggested that IL-12 regulates VEGF in a murine breast ca ncer model. Materials and Methods. Blood from 26 patients with colorectal c ancer was obtained prior to surgery. Plasma levels of VEGF and serum levels of IL,-12 were assessed using the quantitative sandwich enzyme immunoassay technique. We investigated the preoperative relationships between plasma l evels of VEGF, serum levels of IL,-12 and clinicopathological factors in pa tients with colorectal cancer. Results. Although not statistically signific antly, high plasma levels of VEGF ann low serum levels of IL,-12 tended to occur with more advanced colorectal cancer. Plasma levels of VEGF in patien ts who had circumferential involvement of the tumor greater than 1/2 were o nly significantly increased. The preoperative relationship between plasma l evels of VEGF and serum levels of IL,-12 tended to be negatively correlated Conclusion: These results suggest that high plasma levels of IL-12 or low serum levels of IL,-12 may be observed in more advanced colorectal cancer p atients. Thus, these patients may require additional immunochemotherapy aft er surgery. IL,-12 may regulate VEGF in the patients diagnosed with colorec tal cancer.