Tissue culture medium and supplements

Trabectedin (500 nM), oxaliplatin (10 mM), bendamustine (10 mM), Fas ligand (FasL; 500 ng/mL), cisplatin (10 mM), doxorubicin (10 mM), and gemcitabine (10 mM) were prepared as stock solutions dissolved in double-distilled sterile water. Before use, the stock solution was re-diluted in double-distilled sterile water to the desired concentrations. We included various cell lines derived from hematological malignancies: T cell acute lymphoblastic leukemia (Jurkat), Hodgkin’s lymphoma (L1236 and KMH2), chronic myeloid leukemia in blast crisis (K562), and acute myeloblastic leukemia (U937) obtained from the American Type Culture Collection (Manassas, VA, USA) or the German Collection of Microorganisms and Cell Cultures (DSMZ; Braunschweig, Germany). Cells (10,000–240,000 cells/well) were grown in Roswell Park Memorial Institute (RPMI) 1640, supplemented with 2 mM glutamine, 10% (volume/volume) fetal calf serum, 100 units/mL penicillin, 100 μg/mL streptomycin, and 0.25 μg/mL amphotericin B in 5% CO₂. Tissue culture medium and supplements were purchased from Sigma-Aldrich Co, (St Louis, MO, USA). Integrin α4 antibody (VLA-4; C-20) was purchased from Santa Cruz Biotechnology Inc. (Dallas, TX, USA).