The potential chondroprotective effect of celecoxib, a nonsteroidalanti-inflammatory drug and selective cyclooxygenase-2 inhibitor used toreduce pain and inflammation in knee osteoarthritis patients, is disputed.This study aimed at investigating the chondroprotective effects of celecoxibon (1) human articular cartilage explants and (2) in an invivo osteoarthritis rat model. This evidence concerns the gene PTGS2 and osteoarthritis.