2.3. BrdU (Bromodeoxyuridine) Cell Proliferation Assay

Cell proliferation was measured using BrdU Cell Proliferation Assay Kit (Cell Signaling Technology, # 6813S). Cells were seeded in 96-well plates at a density of 8,000 cells per well in triplicate and incubated overnight in DMEM, starving overnight with serum free medium before being exposed to serial dilutions of IL-6 and/or inhibitors for 24 hours at 37 °C to induce proliferation and incorporation of BrdU during S-phase. The rest of procedure was performed following the manufacturer’s instructions. The BrdU incorporation was detected at 450 nm.