Figure S4.

In vitro drug response assay for inhibitors of PI3K and mTOR in human breast cancer cell lines. (A) Western blots for MYC and β-actin control on MCF7 and T47D cell lines transduced with control or MYC-overexpressing lentiviral vectors. Data represent one experiment. (B and C) Dose–response curves of SUM52PE (A) and MDA-MB-468 (B) cell lines transduced with control or MYC-overexpressing lentiviral vectors and treated with everolimus for 3 d. Cell viability was measured by SRB colorimetric assay. Data are represented as mean ± standard deviation of five technical replicas per group of n ≥ 3 independent experiments. (D–G) Representative images (D and F) and corresponding quantification using CellTiter-Blue reagent (E and G) of long-term colony formation assays with MCF7 and T47D cells transduced with control or MYC-overexpressing lentiviral vectors and treated with AZD8055 (D and E) or everolimus (F and G). Cells were treated with indicated drug doses for 10 d, and values were normalized to untreated conditions within each cell line. Data in E and G are represented as mean ± standard deviation of three technical replicas per group of one representative experiment of two independent experiments. (H and I) Dose–response curves of T47D, MCF7, SUM52PE and MDA-MB-468 cell lines transduced with control or MYC-overexpressing lentiviral vectors, treated with alpelisib (H) or buparlisib (I) for 3 d, and measured by SRB colorimetric assay. Data are represented as mean ± standard deviation of five technical replica per group of n ≥ 3 independent experiments.