Evaluation of VEGF and VEGF-C expression in gastric cancer cells producing alpha-fetoprotein

Gastric cancers producing alpha-fetoprotein (AFP) are known to have a poor prognosis and to show a high incidence of liver metastasis. Vascular endothelial growth factor (VEGF) and its isoform VEGF-C are reported to be associated with tumor progression through an angiogenic or lymphangiogenic function. In the present study, to clarify the cellular characteristics of AFP-producing gastric cancers, the expression of VEGF and that of VEGF-C in AFP-producing gastric cancer was compared with their expression in gastric cancers that do not produce AFP. Twenty-six patients with AFP-producing gastric cancers [AFP(+)] and 26 patients with stage-matched gastric cancers that did not produce AFP [AFP(-)] were evaluated for VEGF and VEGF-C expression and vessel density, using immunohistochemical analysis. The survival rate of the AFP(+) group was significantly worse than that of the stage-matched AFP(-) group (P < 0.05). The frequency of VEGF-C expression was significantly higher in the AFP(+) group than in the AFP(-) group (P < 0.01). There was no significant difference in VEGF expression between the AFP(+) and AFP(+) groups. The microvessel density was higher in the AFP(+) group than in the AFP(-) group (P < 0.05). A higher expression of VEGF-C might be one explanation for the poorer prognosis of AFP-producing gastric cancers.