Retinoids as modulators of tumor cells invasion and metastasis.

Retinoids, natural and synthetic analogues of vitamin A, have demonstrated promising results in pre-clinical and clinical trials of cancer prevention and therapy. This chapter reviews the ability of retinoids to suppress tumor growth and metastasis in vivo and to inhibit invasion in vitro. The mechanisms of these effects include suppression of growth and enhancement of differentiation of malignant cells, inhibition of their ability to produce degradative enzymes required for invasion, suppression of migration, inhibition of neovascularization, and augmentation of host anti-tumor immune responses.