Synthesis, Characterization, and Anti-Cancer Activity of Some New N'-(2-Oxoindolin-3-ylidene)-2-propylpentane hydrazide-hydrazones Derivatives

El-Faham, Ayman; Farooq, Muhammad; Khattab, Sherine N.; Abutaha, Nael; Wadaan, Mohammad A.; Ghabbour, Hazem A.; Fun, Hoong-Kun

The stock concentration of the entire compound in DMSO was 10 mM and this concentration was used to prepare the working dilution. The final DMSO concentration used in the experiments was ≤0.5% as the working concentration. Human liver cancer cell lines (HepG2), human leukemia cell line (Jurkat), and human embryonic kidney cell line (HEK293) cells were cultured in high glucose Dulbecco's Modified Eagle Medium (DMEM: Life technologies cat #11995073) supplemented with 10% Fetal bovine serum (FBS: Life technologies cat #16000044) in a humidified incubator with 5% CO2 at 37 °C. Around 2 ×10 3 cells were seeded in each well of a 24-well cell culture plate and were allowed to adhere and grow for 24 h. The Jurkat cells grow in suspension so they were cultured and allowed to grow overnight before the addition of compounds. The compounds in serial dilutions (1, 3, 15, 45, 100, and 300 μM) were added after 24 h of culture and the cells were cultured for another 24 h at 37 °C. The cell viability was determined in each experiment using MTT 1-(4,5-dimethylthiazol-2-yl)-3,5-diphenylformazan colorimetric assay. Briefly, the treated or untreated cells were trypsenized and centrifuged, and the resulting pellet was re-suspended in 100 μL of DMEM serum-free medium and incubated at 37 °C for 2 h. After incubation, 20 μL of MTT solution (5 mg/mL in PBS: Sigma Aldrich cat #M2003) was added to each well and further incubated for 2 h. The plate was centrifuged at 40,000 rpm for 10 min then the medium was removed from each well and 2-propanol containing 0.04 M HCl was added to dissolve the formazan produced in the cells. The optical density of the formazan product in solution was measured with a microplate reader at 540 nm. The experiment was conducted in triplicate. Data were calculated as percent of cell viability by the following formula: % cell viability = (Mean absorbance in test wells/Mean absorbance in control wells) × 100 (1) The IC50 values were calculated from the means of six different concentrations by Bio Data Fit 1.02 using the software Bio Tool Kit (Version 300; Chang Bioscience Inc., Castro Valley, CA, USA) and online program http://ic50.tk/index.html.