MDA-MB438 and MDA-MB231 were maintained in in Dulbecco's modified Eagle's medium (DMEM) supplemented with 10% fetal bovine serum (FBS; Life Technologies, Gaithersburg, MD, USA) and 1% antibiotics/antimycotics (Life Technologies, Gaithersburg, MD, USA).
BT474 were cultured in Roswell Park Memorial Institute (RPMI, Sigma-Aldrich, Saint Louis, Missouri, USA) medium added with 10% FBS and 1% antibiotics/antimycotics.
MCF7 were grown in the base medium ATCC-formulated Eagle's Minimum Essential Medium, (ATCC, Manassas, VA, USA - Catalog No. 30-2003), complemented by 01 mg/ml human recombinant insulin (Sigma-Aldrich, Saint Louis, Missouri, USA), 10% FBS and 1% antibiotics/antimycotics.
KPL4 cell line was kindly provided by Dr Roberto Bianco at Federico II University (Napoli, Italy) and cultivated in DMEM medium with 5% FBS and 1% antibiotics/antimycotics.
The SUM159 cell lines were purchased from Asterand Inc. (Detroit, MI, USA) and were grown in Ham's F-12 medium supplemented with 5% heat-inactivated fetal bovine serum (FBS) and 1% antibiotics/antimycotics (Invitrogen, Carlsbad, CA, USA).
All cell lines were maintained in a humidified incubator with 5% CO2 atmosphere at 37°C.