<p>Legends for supplemental figures</p><p>Figure S1: MLN0128 is more potent than GDC0941 or RAD001 in inhibiting breast cancer cell viability. Viability assays were carried out after 5 days of treatment with the indicated doses of MLN0128, GDC0941, or RAD001 (Selleckchem; Houston, TX) on the following cell lines: (A) SKBR3, (B) MCF7, (C) MCF7/HER2-18. Error bars represent the standard deviation calculated from triplicate wells. Each cell line was analyzed at least three times and a representative experiment is shown.</p><p>Figure S2: MLN0128 and SAHA synergistically inhibit the proliferation of breast cancer cells. (A) Viability assays were performed on MCF7 cells after 3 days of the indicated drug treatments. Error bars represent the standard deviation calculated from triplicate wells. This experiment was performed twice, with three wells per condition each time, and a representative experiment is sown. (B) Combination indices (CI) were calculated using CalcuSyn.</p><p>Figure S3: Dual MLN0128/TSA treatment increases Annexin V and propidium iodide staining in MCF7 cells. MCF7 cells were treated for MLN0128 and/or TSA for 24 hours. Annexin V and propidium iodide (PI) staining was performed as described in materials and methods.</p><p>Figure S4: MLN0128 and TSA have different effects on AKT S473 and T308 phosphorylation. SKBR3 cells were treated with MLN0128 and/or TSA for 8 hours. Whole cell lysates were collected and immunoblots were performed using the indicated antibodies. </p>