PIK3CD and rheumatoid arthritis: In addition, we also observed notable interactions in other parts of the PI3K/AKT/mTOR pathway, including an improved predictive model for the ratio of PI3 kinase PIK3CD and the sodium-potassium ATPase ATP1B1. Interestingly, reduction in synovial expression of PIK3CD has been linked with response to anti-TNF therapy in RA patients [40, 41].