Receptors for tumor-promoting phorbol esters in rat ventral prostate.

Abstract

The presence of tumor-promoting phorbol ester receptors in rat prostate was investigated by studying the binding of phorbol diester 12,13-dibutyrate (PDBu) in both soluble and particulate subcellular fractions. Binding of [3H]PDBu to the soluble fraction was optimal after the addition of phosphatidylserine (0.1 mg/ml) and Ca2+ (1 mM). Both subcellular fractions exhibited a single class of PDBu receptor (Kd between 97 and 128 nM) as shown by saturation binding experiments. Phorbol esters with tumor-promoting activity showed a higher affinity for these receptors than did endogenous ligands such as diacylglycerols whereas phorbol esters without tumor-promoting activity were ineffective even at concentrations as high as 1 microM. These properties are highly representative of protein kinase C activity.

• Authors: M J Carmena, M P Garcia-Paramio, J C Prieto
• Journal: Cancer letters (Cancer Lett) Vol. 68 Issue 2-3 Pg. 143-7 (Feb 1993) ISSN: 0304-3835 [Print] Ireland
• PMID: 8443786 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Caenorhabditis elegans Proteins
• Carrier Proteins
• Phorbol Esters
• Phosphatidylserines
• Receptors, Drug
• phorbol ester binding protein
• phorbol ester receptor
• Protein Kinase C
• Calcium

Topics

• Animals
• Caenorhabditis elegans Proteins
• Calcium (pharmacology)
• Carrier Proteins
• Male
• Phorbol Esters
• Phosphatidylserines (pharmacology)
• Prostate (metabolism)
• Protein Kinase C
• Rats
• Rats, Wistar
• Receptors, Drug (analysis)
• Signal Transduction
• Subcellular Fractions (metabolism)