The present study tested the hypothesis that the production of vascular endothelial growth factor C (VEGF-C), a key lymphangiogenic factor, by human breast cancer cells can be stimulated by human lectins, using plant lectins as controls.
Materials and methods: The effects of human galectins and five plant lectins reacting with distinct determinants of N- and O-glycans on the accumulation of VEGF-C in serum-free cell culture media of human breast cancer cells endowed with high (MDA-MB-231) and low (MCF7, T-47D, and SK-BR-3) VEGF-C-producing abilities were examined.
Results: All tested lectins stimulated VEGF-C production by MDA-MB-231 cells, albeit with different potency. Concanavalin A, but not galectins, was also able to stimulate VEGF-C production by low VEGF-C-producing cell lines MCF7 and T-47D. Both VEGF-C mRNA and protein were strongly up-regulated in SK-BR-3 cells by concanavalin A and wheat germ agglutinin, but not jacalin.
Conclusion: The differential response of breast cancer cell lines separated by the endogenous level of VEGF-C production suggests that galectins may contribute to tumor-associated lymphangiogenesis in a cell-specific manner.