To determine whether the regulation of miR29b and DNMT3B levels by CD28 involved activation of the PI3K/AKT pathway, we simultaneously exposed U266 and RPMI 8226 myeloma cells to CD28 stimulation and PI3K inhibition with the PI3K inhibitors LY294002 and buparlisib (Fig. 2). This evidence concerns the gene AKT1 and plasma cell myeloma.