Progesterone receptor (PGR) gene is associated with the action of the hormone progesterone, which is involved in egg cells development in humans and other mammals [1], as well as in maintaining healthy pregnancy [2].

Some variants of this gene are associated with preterm birth [3], endometriosis [4] and several cancers, such as breast cancer, cancer of the uterus and ovaries [5].

There are also reports that show some variants of PGR are associated with late onset of a migraine [6], as progesterone influences the activity of nerve cells as well [6].

Progesterone receptor has two forms, PR-A and PR-B [7] that are produced under the influence of another hormone “ estrogen, but their production is still based on information from the same gene [8].

PR-A inhibits most hormone receptors, whereas PR-B is an activator of gene activity [9].

In pregnancy, PR-B ensures the relaxation of the uterus whereas PR-A promotes labor [10].

Because of the different action of two receptor variants, there is conflicting evidence concerning the involvement of progesterone receptor in the development of diseases, such as cancer.

In some reports it is shown that activity of PGR gene is related to events that support tumor growth, such as development of blood vessels in the tumor in case of small-cell lung cancer [11] and in different conditions the activity of progesterone receptor can be both beneficial and detrimental in breast cancer and determines the response to hormonal treatment for this disease [12].

Other studies show that one of the variants of progesterone receptor, PR-B, can promote cell death in breast cancer cells [13].

     From NCBI Gene: Progesterone resistance

     From NCBI Gene: This gene encodes a member of the steroid receptor superfamily. The encoded protein mediates the physiological effects of progesterone, which plays a central role in reproductive events associated with the establishment and maintenance of pregnancy. This gene uses two distinct promotors and translation start sites in the first exon to produce several transcript variants, both protein coding and non-protein coding. Two of the isoforms (A and B) are identical except for an additional 165 amino acids found in the N-terminus of isoform B and mediate their own response genes and physiologic effects with little overlap. [provided by RefSeq, Sep 2015] From UniProt: The steroid hormones and their receptors are involved in the regulation of eukaryotic gene expression and affect cellular proliferation and differentiation in target tissues. Progesterone receptor isoform B (PRB) is involved activation of c-SRC/MAPK signaling on hormone stimulation. Isoform A: inactive in stimulating c-Src/MAPK signaling on hormone stimulation. Isoform 4: Increases mitochondrial membrane potential and cellular respiration upon stimulation by progesterone.

The following transcription factors affect gene expression:

• p53
• NF-kappaB1
• PPAR-alpha
• Sp1
• TBP
• NF-1
• TFIID
• c-Myb

Molecular Function:

• Atpase Binding
• Dna Binding
• Enzyme Binding
• Receptor Binding
• Rna Polymerase Ii Core Promoter Proximal Region Sequence-Specific Dna Binding
• Steroid Binding
• Steroid Hormone Receptor Activity
• Transcriptional Activator Activity, Rna Polymerase Ii Core Promoter Proximal Region Sequence-Specific Binding
• Zinc Ion Binding

Biological Processes:

• Cell-Cell Signaling
• Negative Regulation Of Gene Expression
• Positive Regulation Of Transcription From Rna Polymerase Ii Promoter
• Signal Transduction
• Transcription Initiation From Rna Polymerase Ii Promoter

Drug Bank:

• Danazol
• Desogestrel
• Drospirenone
• Fluticasone Propionate
• Hydroxyprogesterone Caproate
• Norethisterone
• Ethynodiol
• Levonorgestrel
• Medroxyprogesterone Acetate
• Megestrol Acetate
• Mifepristone
• Norelgestromin
• Norgestimate
• Progesterone
• Spironolactone
• Dydrogesterone
• Allylestrenol
• Etonogestrel
• Ulipristal