Encyclopedia of Cancer

Living Edition
| Editors: Manfred Schwab

Orphan Nuclear Receptors

  • Subhajit Mukherjee
  • Sridhar Mani
Living reference work entry
DOI: https://doi.org/10.1007/978-3-642-27841-9_4262-4



The word “orphan” means lacking “support, supervision, or care” (The American Heritage® dictionaries) and when applied as an adjective to nuclear receptors implies that these receptors do not have a defined ligand (for which no ligand is known). This definition is paradoxic in the sense that a “receptor” implies that there is a physiologic ligand even though that ligand has not been discovered. At present, there is no consensus in the field with regard to the presence or absence of ligands for all orphan receptors. Once a physiologic ligand is discovered for a particular receptor, then that receptor no longer belongs in the “orphan” category (adopted orphan receptors); however, there are examples of liganded receptors (e.g., RXR, PPARs) where the controversy surrounds the identity of...


Nuclear Receptor Orphan Receptor Orphan Nuclear Receptor Physiologic Ligand Corepressor Complex 
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See Also

  1. (2012) Cell Differentiation. In: Schwab M (ed) Encyclopedia of Cancer, 3rd edn. Springer Berlin Heidelberg, pp 737–738. doi:10.1007/978-3-642-16483-5_998Google Scholar
  2. (2012) Circadian. In: Schwab M (ed) Encyclopedia of Cancer, 3rd edn. Springer Berlin Heidelberg, p 858. doi:10.1007/978-3-642-16483-5_1172Google Scholar
  3. (2012) Cutaneous T-Cell Lymphoma. In: Schwab M (ed) Encyclopedia of Cancer, 3rd edn. Springer Berlin Heidelberg, p 1021. doi:10.1007/978-3-642-16483-5_1416Google Scholar
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  5. (2012) Nuclear Receptor. In: Schwab M (ed) Encyclopedia of Cancer, 3rd edn. Springer Berlin Heidelberg, p 2571. doi:10.1007/978-3-642-16483-5_4157Google Scholar

Copyright information

© Springer-Verlag Berlin Heidelberg 2014

Authors and Affiliations

  1. 1.Albert Einstein College of MedicineNew YorkUSA
  2. 2.Department of Medicine, Oncology and Molecular GeneticsAlbert Einstein College of MedicineNew YorkUSA