Retinoids (ie, vitamin A, all-trans retinoic acid, and related signaling molecules) induce the
differentiation of various types of stem cells. Nuclear retinoic acid receptors mediate most but
not all of the effects of retinoids. Retinoid signaling is often compromised early in
carcinogenesis, which suggests that a reduction in retinoid signaling may be required for
tumor development. Retinoids interact with other signaling pathways, including estrogen
signaling in breast cancer. Retinoids are used to treat cancer, in part because of their ability …