The cells were exposed to each drug for 24 hours; the medium containing the first drug was removed, the cells were washed with phosphate buffered saline, then medium containing the second drug was added to the cells. The total culture time was 72 hours. A CI < 0.3, 0.3–0.7, 0.7–0.9, 0.9–1.1, 1.1–1.45, 1.45–3.3 and >3.3 indicates Verubecestat price highly synergistic, synergistic, moderate to slight synergistic, nearly additive, slight to moderate antagonistic, antagonistic; strong antagonistic, respectively (CalcuSyn software, v. 2, Biosoft, Cambridge, UK). Flow cytometry Flow cytometric measurements
were performed after staining the cellular DNA content with propidium iodide to determine the cell cycle distribution and apoptosis following treatment with sequential gemcitabine → paclitaxel or paclitaxel → gemcitabine. Briefly, ~1 × 106 cells were plated in 60 mm dishes and allowed to attach overnight. After treatment with sequential gemcitabine → paclitaxel or paclitaxel → gemcitabine as {Selleck Anti-infection Compound Library|Selleck Antiinfection Compound Library|Selleck Anti-infection Compound Library|Selleck Antiinfection Compound Library|Selleckchem Anti-infection Compound Library|Selleckchem Antiinfection Compound Library|Selleckchem Anti-infection Compound Library|Selleckchem Antiinfection Compound Library|Anti-infection Compound Library|Antiinfection Compound Library|Anti-infection Compound Library|Antiinfection Compound Library|Anti-infection Compound Library|Antiinfection Compound Library|Anti-infection Compound Library|Antiinfection Compound Library|Anti-infection Compound Library|Antiinfection Compound Library|Anti-infection Compound Library|Antiinfection Compound Library|Anti-infection Compound Library|Antiinfection Compound Library|Anti-infection Compound Library|Antiinfection Compound Library|Anti-infection Compound Library|Antiinfection Compound Library|buy Anti-infection Compound Library|Anti-infection Compound Library ic50|Anti-infection Compound Library price|Anti-infection Compound Library cost|Anti-infection Compound Library solubility dmso|Anti-infection Compound Library purchase|Anti-infection Compound Library manufacturer|Anti-infection Compound Library research buy|Anti-infection Compound Library order|Anti-infection Compound Library mouse|Anti-infection Compound Library chemical structure|Anti-infection Compound Library mw|Anti-infection Compound Library molecular weight|Anti-infection Compound Library datasheet|Anti-infection Compound Library supplier|Anti-infection Compound Library in vitro|Anti-infection Compound Library cell line|Anti-infection Compound Library concentration|Anti-infection Compound Library nmr|Anti-infection Compound Library in vivo|Anti-infection Compound Library clinical trial|Anti-infection Compound Library cell assay|Anti-infection Compound Library screening|Anti-infection Compound Library high throughput|buy Antiinfection Compound Library|Antiinfection Compound Library ic50|Antiinfection Compound Library price|Antiinfection Compound Library cost|Antiinfection Compound Library solubility dmso|Antiinfection Compound Library purchase|Antiinfection Compound Library manufacturer|Antiinfection Compound Library research buy|Antiinfection Compound Library order|Antiinfection Compound Library chemical structure|Antiinfection Compound Library datasheet|Antiinfection Compound Library supplier|Antiinfection Compound Library in vitro|Antiinfection Compound Library cell line|Antiinfection Compound Library concentration|Antiinfection Compound Library clinical trial|Antiinfection Compound Library cell assay|Antiinfection Compound Library screening|Antiinfection Compound Library high throughput|Anti-infection Compound high throughput screening| described for the determination of the CI, the Ferroptosis targets cells were harvested and suspended in a propidium iodide solution (Sigma-Aldrich Co.) as described previously [21] and filtered in 5 ml round bottom tube with cell-strainer cap (BD Falcon). The cell cycle analysis
was performed on a Beckman-Coulter EPICS Elite ESP flow cytometer (Hialeah, Florida, USA) using the Multicycle AV program (v. 3, Phoenix Flow Systems, San
Diego, Calfornia, USA). dCK and CDA enzyme specific activity The effect of paclitaxel on dCK and CDA enzyme specific activity was measured after exposing ~20–30 × 106 cells (seeded in Oxymatrine duplicate in 100 mm dishes) to either vehicle-control or paclitaxel at the observed IC50 value for 24 hours. Cells were manually harvested and counted. Total protein was quantified using BCA protein kit (Pierce Biotechnology, Rockford, Illinois, USA) dCK activity was analyzed using radiolabeled chlorodeoxyadenosine (CdA) as previously described [22, 23]. Briefly, the crude cellular extract was suspended in Tris-HCl buffer and mixed with CdA 256.5 μM plus [8-3H]-CdA (128 μM, specific activity 0.19 μCi/nmol) as substrate. The enzymatic reaction was incubated for 1 hour at 37°C. Enzyme activities were expressed as nmol product formed per hour per mg protein or 106 cells. The CDA activity was measured using a spectrophotometric method as described by Dr. Vincenzetti [24]. The crude cellular extract was suspended in a Tris-HCl buffer and freeze-thawed rapidly three times. The extract was subsequently centrifuged for 15 minutes at 12,000 g and the resulting supernatant was suspended in the Tris-HCl buffer. The enzymatic reaction was performed in a 96 well UV-Vis transparent plate (BD Falcon) and initiated with the addition of the substrate cytidine (167 μM).