Characterization of TNBC Cell Lines

Human TNBC cell lines MDAMB468, HCC1806, HCC1569, Hs578t, BT549, MDAMB231, and HCC1937 (Wu et al., 2015 (link)) were procured from American Type Culture Collection (ATCC, Manassas, VA), revived from early passage liquid nitrogen vapor stocks as required and maintained at 37°C in 5% CO₂ and 95% humidity. All cells were authenticated via short tandem repeat testing. No mycoplasma contamination was noted. DAPT and GANT61 were procured from Sigma-Aldrich, St. Louis, MO, and Selleck Chemicals, Houston, TX. For Western blot, immunoprecipitation, immunofluorescence and immunohistochemistry, anti-ALDH1A, anti-Nanog, anti-Oct4, anti-KLF4, anti-c-MYC, anti-NICD, anti-JAGGED, and anti-Ki67 antibodies were purchased from Cell Signaling Technology, Beverly, MA. Antibodies anti-GLI1, anti-Sox2, anti-SHH, anti-FOXM1, and anti-HES1 were procured from Santa Cruz Biotechnology Inc Anti-HEY1 was purchased from ABclonal Technology, Woburn, MA. Mouse monoclonal β-Actin was procured from Sigma-Aldrich, St. Louis, MO. Horseradish peroxidase conjugated goat anti-rabbit IgG, goat anti-mouse IgG, and donkey anti-goat IgG were purchased from Sigma-Aldrich, St. Louis, MO. 3-(4,5-Dimethylthiazol-2-yl)–2,5-diphenyltetrazolium bromide (MTT) were procured from Sigma-Aldrich, St Louis, MO. Chemiluminescent peroxidase substrate was procured from GE Healthcare, UK.