A Randomized Trial of Somatostatin to Regulate the VEGFs/VEGFRs in Patients with Gastric Cancer

Angiogenesis and lymphangiogenesis are essential for tumor growth and metastasis. Vascular endothelial growth factors and their receptors (VEGFs/VEGFRs) are important to modulate vasculogenesis. Disregulation of the VEGFs/VEGFRs are closely related to tumor progression and prognosis.We established an open-label, randomized trial to assess the effect of somatostatin on the patients with primary gastric cancer and total gastrectomy. All the 60 patients were randomly divided into somatostatin pretreatment and placebo groups and we used ELISA, real-time PCR and immunohistochemistry analysis to identify the level of VEGFs.The results showed that the patients pretreated with somatostatin had a significant decrease in serum VEGF level, but not in the tissue mRNA level, and the decrease in serum VEGF was partially dependent on the synthesis and degradation of the protein but not the transcription of mRNA. We also found the tissue Flt-4 (VEGFR-3) protein decreased in somatostatin pretreatment group.We concluded that somatostatin exerts its anti-vasculogenesis effect by downregulating the serum VEGFs and Flt-4 level. Somatostatin can be used as an important adjuvant to improve the survival of gastric cancer patients.