It is highly likely that breast cancer cells in situ are also heterogeneous in expression of different VEGF-C receptors, similar to the breast cancer cell lines employed in the present study, and the receptor bearing cells would respond to both endogenous and exogenous (produced by other cells such as macrophages (Schoppmann et al, 2006) in the breast cancer stroma) VEGF-C in the tumour microenvironment. This evidence concerns the gene VEGFC and breast carcinoma.