Tracking progesterone receptor-mediated actions in breast cancer

Research output: Contribution to journalReview articlepeer-review

61 Scopus citations


Ovarian steroid hormones contribute to breast cancer initiation and progression primarily through the actions of their nuclear transcription factors, the estrogen receptor alpha (ERα) and progesterone receptors (PRs). These receptors are important drivers of the luminal A and B subtypes of breast cancer, where estrogen-blocking drugs have been effective endocrine therapies for patients with these tumors. However, many patients do not respond, or become resistant to treatment. When endocrine therapies fail, the luminal subtypes of breast cancer are more difficult to treat because these subtypes are among the most heterogeneous in terms of mutation diversity and gene expression profiles. Recent evidence suggests that progestin and PR actions may be important drivers of luminal breast cancers. Clinical trial data has demonstrated that hormone replacement therapy with progestins drives invasive breast cancer and results in greater mortality. PR transcriptional activity is dependent upon cross-talk with growth factor signaling pathways that alter PR phosphorylation, acetylation, or SUMOylation as mechanisms for regulating PR target gene selection required for increased cell proliferation and survival. Site-specific PR phosphorylation is the primary driver of gene-selective PR transcriptional activity. However, PR phosphorylation and heightened transcriptional activity is coupled to rapid PR protein degradation; the range of active PR detected in tumors is likely to be dynamic. Thus, PR target gene signatures may provide a more accurate means of tracking PR's contribution to tumor progression rather than standard clinical protein-based (IHC) assays. Further development of antiprogestin therapies should be considered alongside antiestrogens and aromatase inhibitors.

Original languageEnglish (US)
Pages (from-to)114-125
Number of pages12
JournalPharmacology and Therapeutics
Issue number1
StatePublished - Apr 2014

Bibliographical note

Funding Information:
This work was supported by the National Institutes of Health grant number R01 CA123763 (formerly R01 DK5382) and R01 CA159712 (to C.A.L), P30 CA077598 , and the Department of Defense Breast Cancer Research Program grant number BC093529 (to T.P.K.).


  • Antiprogestins
  • Estrogen receptor (ER)
  • Gene expression
  • Phosphorylation
  • Progesterone receptor (PR)
  • SUMOylation


Dive into the research topics of 'Tracking progesterone receptor-mediated actions in breast cancer'. Together they form a unique fingerprint.

Cite this