mean 6 SEM (n = 3);*, P,0.05;**, P,0.01;***, represent P,0.001. (TIF) Figure S6 Increased cellular levels of O-GlcNAc increas- es resistance of the T-47D tumor cell line to GDC-0941 and alters the phosphorylation state of ERBB3. A, T-47D cells treated with 100 mM PUGNAc, in the presence or absence of 100 nM GDC-0941. Cell viability was assayed at 0, 24, 48, and 72 hours post-transfection and treatment with GDC-0941. B, Immunoblot analysis of whole cell lysates from T-47D cells using anti-OGT or anti-O-GlcNAc antibodies. Cells were treated with 100 mM PUGNAc or DMSO control for 24 hours, as indicated. C, Immunoblot analysis of whole cell lysates from T-47D cells with indicated antibodies. Cell treatments are as indicated. D, Quantitative phosphorylation analysis of ERBB3 (PanY) in T- 47D cells treated with 100 mM PUGNAc, in the presence or absence of 100 nM GDC-0941 for 24 hours. Cells were treated with 100 nM GDC-0941 or DMSO control for 24 hours, as indicated. 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Wagner EF, Nebreda AR (2009) Signal integration by JNK and p38 MAPK pathways in cancer development. Nat Rev Cancer 9: 537–549. PLOS ONE | www.plosone.org 12 September 2012 | Volume 7 | Issue 9 | e46518