Molecular Classification
Enzyme, Cysteine protease, Papain family protease
Other Names
Cathepsin O2, CatK
Disease Roles
PycnodysostosisOsteoporosisArthritis

Cathepsin K Overview

Cathepsin K (CTSK) is a lysosomal cysteine protease that belongs to the papain family. It is primarily expressed in osteoclasts and plays a crucial role in bone remodeling and resorption by degrading collagen and other matrix proteins. It has also been implicated in other biological processes, including thyroid hormone release and cancer progression, making it a therapeutic target for conditions like osteoporosis and certain cancers. Its activity can be stimulated by inflammatory cytokines.

Mechanism of Action

Inhibition of Cathepsin K enzymatic activity, reducing bone resorption.

Biological Functions

Bone resorption
Extracellular matrix degradation
Thyroid hormone release
Endopeptidase activity

Disease Associations

Pycnodysostosis
Osteoporosis
Arthritis
Atherosclerosis
Cancer

Safety Considerations

  • Increased risk of stroke (Odanacatib)
  • Potential for off-target effects due to protease activity

Interacting Drugs

Odanacatib
MIV-711