R-Ketorolac Targets Cdc42 and Rac1 and Alters Ovarian Cancer Cell Behaviors Critical for Invasion and Metastasis

Mol Cancer Ther. 2015 Oct;14(10):2215-27. doi: 10.1158/1535-7163.MCT-15-0419. Epub 2015 Jul 23.


Cdc42 (cell division control protein 42) and Rac1 (Ras-related C3 botulinum toxin substrate 1) are attractive therapeutic targets in ovarian cancer based on established importance in tumor cell migration, adhesion, and invasion. Despite a predicted benefit, targeting GTPases has not yet been translated to clinical practice. We previously established that Cdc42 and constitutively active Rac1b are overexpressed in primary ovarian tumor tissues. Through high-throughput screening and computational shape homology approaches, we identified R-ketorolac as a Cdc42 and Rac1 inhibitor, distinct from the anti-inflammatory, cyclooxygenase inhibitory activity of S-ketorolac. In the present study, we establish R-ketorolac as an allosteric inhibitor of Cdc42 and Rac1. Cell-based assays validate R-ketorolac activity against Cdc42 and Rac1. Studies on immortalized human ovarian adenocarcinoma cells (SKOV3ip) and primary patient-derived ovarian cancer cells show that R-ketorolac is a robust inhibitor of growth factor or serum-dependent Cdc42 and Rac1 activation with a potency and cellular efficacy similar to small-molecule inhibitors of Cdc42 (CID2950007/ML141) and Rac1 (NSC23766). Furthermore, GTPase inhibition by R-ketorolac reduces downstream p21-activated kinases (PAK1/PAK2) effector activation by >80%. Multiple assays of cell behavior using SKOV3ip and primary patient-derived ovarian cancer cells show that R-ketorolac significantly inhibits cell adhesion, migration, and invasion. In summary, we provide evidence for R-ketorolac as a direct inhibitor of Cdc42 and Rac1 that is capable of modulating downstream GTPase-dependent, physiologic responses, which are critical to tumor metastasis. Our findings demonstrate the selective inhibition of Cdc42 and Rac1 GTPases by an FDA-approved drug, racemic ketorolac, that can be used in humans.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Allosteric Regulation
  • Aminoquinolines / pharmacology
  • Antineoplastic Agents / pharmacology*
  • Carcinoma, Ovarian Epithelial
  • Cell Adhesion
  • Cell Line, Tumor
  • Cell Movement
  • Dose-Response Relationship, Drug
  • Female
  • Guanosine Triphosphate / metabolism
  • Humans
  • Ketorolac / pharmacology*
  • Neoplasm Invasiveness
  • Neoplasm Metastasis
  • Neoplasms, Glandular and Epithelial / drug therapy*
  • Neoplasms, Glandular and Epithelial / metabolism
  • Neoplasms, Glandular and Epithelial / pathology
  • Ovarian Neoplasms / drug therapy*
  • Ovarian Neoplasms / metabolism
  • Ovarian Neoplasms / pathology
  • Protein Binding
  • Pseudopodia
  • Pyrimidines / pharmacology
  • Signal Transduction
  • cdc42 GTP-Binding Protein / antagonists & inhibitors*
  • cdc42 GTP-Binding Protein / metabolism
  • rac1 GTP-Binding Protein / antagonists & inhibitors*
  • rac1 GTP-Binding Protein / metabolism


  • Aminoquinolines
  • Antineoplastic Agents
  • NSC 23766
  • Pyrimidines
  • RAC1 protein, human
  • Guanosine Triphosphate
  • cdc42 GTP-Binding Protein
  • rac1 GTP-Binding Protein
  • Ketorolac