Effect of dasatinib and TBB treatment on phosphorylation of Src and NF-kappaB related proteins. Experiments were run in duplicate and showed similar results in two cell lines (402-91 and 1765-92) and primary cultures (L1357 and L2187). Treatment of L1357 with dasatinib did not affect total levels of Src, but gradually decreased P-Src levels at 200 nM to almost absence at 500 nM. There was no effect of dasatinib on total p65 and phosphorylated-p65 levels. Treatment of L1357 with TBB did not affect total levels of p65, but gradually decreased P-p65 levels at 200 μM. TBB treatment had no effect on the levels of total Src and phosphorylated Src. Interestingly, TBB and dasatinib showed enhancement to decrease levels of phosphorylated Src and p65. Strikingly, there was a gradual increase in caspase-3 levels upon treatment with TBB, which was enhanced by combination with dasatinib, suggesting caspase-3 mediated apoptosis underlying the observed decrease in cell viability. Abbreviations: DAS50 = dastinib 50 nM, etc. DAS and TBB = 200 μM dasatinib and IC50 concentration for TBB.