Progesterone receptor (PR) (PGR)

The Progesterone receptor (PR) is a ligand-activated transcription factor belonging to the nuclear receptor superfamily, specifically the steroid hormone receptor group (UniProt: P06401). It exists primarily in two isoforms, PR-A and PR-B, which are encoded by the PGR gene and play distinct roles in mediating the biological effects of progesterone (NCBI Gene: 5241). PR is essential for the regulation of the female reproductive system, including the coordination of the menstrual cycle, preparation of the uterine lining for embryo implantation, and the maintenance of pregnancy (StatPearls: Progesterone). In addition to its reproductive roles, PR is a key driver in the development of mammary glands and is frequently used as a diagnostic biomarker in breast cancer to determine hormone sensitivity and guide treatment (PubMed: PMC3136063). Therapeutic agents like levonorgestrel act as potent PR agonists to prevent ovulation and thicken cervical mucus for contraception, while PR antagonists like mifepristone are used for pregnancy termination and the management of uterine fibroids (PubChem: Levonorgestrel).

Other names

PGRNR3C3Nuclear receptor subfamily 3 group C member 3PR

Drugs targeting the progesterone receptor act as agonists, antagonists, or selective progesterone receptor modulators (SPRMs) to either activate or inhibit the transcription of progesterone-responsive genes.