PI3 kinase inhibition increases Bid cleavage. Rheumatoid arthritis (RA) fibroblast-like synoviocytes (FLS) were left untreated (Basal) or treated for 12 hours with 1 μg/ml anti-Fas antibody or pretreated for one hour with phosphoinositol-3 (PI3) kinase inhibitor Wortmannine (Wort) before Fas stimulation. Expression of (a) phosphoAkt and (b) Bid was analysed by western blot. Data are expressed as mean (standard error of the mean) of FLS from six different RA patients. * indicates P < 0.05, ** indicates P < 0.01 and *** indicates P < 0.001. (c) A representative blot is shown.