Leukemia progression of TEL-AML1⁺ cell lines and survival of t(12;21) primary leukemia cells is impaired by STAT3 inhibition. Leukemia progression of TEL-AML1⁺ cell lines and survival of t(12;21) primary leukemia cells is impaired by STAT3 inhibition. (A) Kaplan-Meier survival curve for NSG mice transplanted with control scramble (n = 7) or shSTAT3 (n = 8) transduced Reh cells. P = .0002 versus scramble control (Mantel-Cox log-rank test). (B) Viability as measured by MTS assay of 4 independent TEL-AML1⁺ primary human leukemic samples after treatment with different S3I-201 concentrations for 96 hours. The response of Reh cells is included as a reference (C). Percentage apoptosis of 2 different primary human leukemic samples after 24-hour exposure to 50 µM S3I-201. (D) Western blot analysis of MYC protein expression in primary cells 24 hours after treatment with 50 µM S3I-201. **P < .01, ***P < .005 compared with control (Student unpaired t test). DMSO, dimethylsulfoxide; GAPDH, glyceraldehyde-3-phosphate dehydrogenase.