Growth factors and their receptors in metastasis.

The process of metastasis is not random. Rather, the outcome depends on the interaction of unique metastic cells with different organ microenvironments. Although the ability of some tumor cells to reach and proliferate in the parenchyma of some organs is responsible for the development of site-specific metastasis, the molecular basis of organ-specific metastasis is unclear. This article will address the molecular mechanisms involved in the interaction between favored tumor cells and a compatible organ environment in terms of growth factors and those receptors participating in paracrine and autocrine signal transduction pathways.