ERG Transcriptional Networks in Primary Acute Leukemia Cells Implicate a Role for ERG in Deregulated Kinase Signaling
Figure 5
ERG overexpression induced resistance to multi-kinase inhibitors. A)
K562 cells transduced with the inducible ERG expression vector (induced indicated as +DOX and uninduced indicated as –DOX) were treated with 10 µM Sorafenib in 5 parallel wells. Following 48 hours, cell proliferation was measured with WST-1 at 450 nm absorbance. Jurkat cells were transiently transfected with ERG expression vector, pDom-ERG, and the control vector pDom-empty. Twenty-four hours after seeding transiently transfected cells in 5 parallel wells, Sorafenib was added to a final concentration of 10 µM. Cell proliferation was measured 48 hours after drug addition. Cell proliferation was measured with WST-1 reagent at the 450 nm absorbance. Cell proliferation was measured with WST-1 in Jurkat cells transiently transfected with ERG expression vector pDom-ERG and the control vector pDom-empty. Twenty-four hours following transient transfection of pDom-ERG and pDom-empty, TKI258 was added to a final concentration of 1 µM. Cell proliferation was analyzed as described above. Bar graphs display the average of 5 experiments. Statistical significance was analyzed using Wilcoxon rang sum test. Asterisk indicates statistically significant results. *: P<0.05. B and C) ERG (+Dox and −Dox) K562 cells were treated with 10 µM Sorafenib or 10 µM TKI258 for 72 hours in order to determine the effects of drug induced apoptosis by Annexin V-FITC detection. This was conducted in two independent ERG inducible K562 Tet-on clones and one of two independent experiments is represented by dot plots.