Mda mb 231

The human breast cancer cell lines MCF-7 and MDA-MB-231 was purchased from the Shanghai Institute of Cell Biology, Chinese Academy of Sciences (Shanghai, China). TGF-β1 was purchased from R&D Systems (Minneapolis, MN). Antibodies were from various sources: anti-E-cadherin antibody (BD Biosciences, Bedford, MA), anti-SLUG antibody (Cell Signaling, Beverley, MA), anti-SNAIL1 and anti-α-tubulin antibodies (Santa Cruz Biotechnology, Santa Cruz, CA). Antibody used for immunofluorescence staining in MCF-7 and MDA-MB-231 cells was anti-E-cadherin (BD Biosciences, Bedford, MA).

BLTN cell lines SUM1315 and MDA-MB-231 were obtained from Asterand. SUM1315 cells were seeded at 25 000 cells per mL in 75 cm² culture dish (Falcon®) at 37°C under 5% CO₂, in 15 mL Ham's F12 medium (Gibco®) supplemented with 5% decomplemented fetal calf serum, 10 mM HEPES^* buffer, 20 mg/mL gentamycin, 10 ng/mL EGF and 4 μg/mL of insulin, according to the supplier's instructions [29 (link), 30 (link)]. The MDA-MB-231 cell line was seeded at 25 000 cells per mL in 75 cm² culture dish (Falcon ®) at 37°C under 5% CO₂, in 15 mL RPMI 1640 medium (Gibco®) supplemented with 10% decomplemented fetal calf serum and 20 mg/mL gentamycin, according to the supplier's instructions [29 (link), 30 (link)].
Cells having reached confluence were washed with Phosphate Buffer Saline (PBS, 1X, Sigma®) and Trypsinized (Trypsin 1X, Sigma®) for 5 min at 37°C. Cells were taken up in 12 mL of culture medium and centrifuged for 10 minutes at 250 G. The pellet was taken up in 5 mL of culture medium and the number of cells per mL was determined by a cell count using a vital stain Trypan Blue. This allowed for counting the cell dilutions necessary for seeding cells in varying concentrations and defined for each experiment.