Summary of signaling networks and pathways regulated by the glucocorticoid receptor. Targets of liganded and unliganded GR appear to possess opposing functions in the breast. While liganded GR is involved in maintaining functional differentiation, such as occurs during lactation, several unliganded GR targets appear to be pro-apoptotic, and may be involved in involution. Factors in blue represent known targets of liganded GR signaling. Factors in purple represent targets revealed by our microarray to be positively regulated by unliganded GR. Targets in bold purple represent candidates investigated during our microarray validation.