Blockade of PI3Kgamma suppresses joint inflammation and damage in mouse models of rheumatoid arthritis

Nat Med. 2005 Sep;11(9):936-43. doi: 10.1038/nm1284. Epub 2005 Aug 28.


Phosphoinositide 3-kinases (PI3K) have long been considered promising drug targets for the treatment of inflammatory and autoimmune disorders as well as cancer and cardiovascular diseases. But the lack of specificity, isoform selectivity and poor biopharmaceutical profile of PI3K inhibitors have so far hampered rigorous disease-relevant target validation. Here we describe the identification and development of specific, selective and orally active small-molecule inhibitors of PI3Kgamma (encoded by Pik3cg). We show that Pik3cg(-/-) mice are largely protected in mouse models of rheumatoid arthritis; this protection correlates with defective neutrophil migration, further validating PI3Kgamma as a therapeutic target. We also describe that oral treatment with a PI3Kgamma inhibitor suppresses the progression of joint inflammation and damage in two distinct mouse models of rheumatoid arthritis, reproducing the protective effects shown by Pik3cg(-/-) mice. Our results identify selective PI3Kgamma inhibitors as potential therapeutic molecules for the treatment of chronic inflammatory disorders such as rheumatoid arthritis.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Arthritis, Rheumatoid / chemically induced
  • Arthritis, Rheumatoid / drug therapy*
  • Binding Sites
  • Chemotaxis, Leukocyte / drug effects
  • Dioxoles / chemistry
  • Dioxoles / therapeutic use*
  • Disease Models, Animal
  • Enzyme Inhibitors / therapeutic use*
  • Isoenzymes
  • Mice
  • Mice, Inbred BALB C
  • Mice, Inbred C3H
  • Mice, Inbred DBA
  • Mice, Knockout
  • Molecular Sequence Data
  • Molecular Structure
  • Peritonitis / chemically induced
  • Peritonitis / drug therapy
  • Phosphatidylinositol 3-Kinases / chemistry
  • Phosphoinositide-3 Kinase Inhibitors*
  • Quinoxalines / chemistry
  • Quinoxalines / therapeutic use*
  • Signal Transduction
  • Structure-Activity Relationship
  • Thiazolidinediones / chemistry
  • Thiazolidinediones / therapeutic use*


  • 5-(2,2-difluorobenzo(1,3)dioxol-5-ylmethylene)thiazolidine-2,4-dione
  • 5-quinoxalin-6-ylmethylenethiazolidine-2,4-dione
  • Dioxoles
  • Enzyme Inhibitors
  • Isoenzymes
  • Phosphoinositide-3 Kinase Inhibitors
  • Quinoxalines
  • Thiazolidinediones

Associated data

  • GENBANK/AF327656
  • GENBANK/AS604850
  • GENBANK/AS605240
  • GENBANK/M61906
  • GENBANK/S67334
  • GENBANK/U79143
  • GENBANK/U86453
  • PDB/2A4Z
  • PDB/2A5U