Synergistic Effect of Dexamethasone and Diclofenac on Viability of K562 Cells

Chronic myeloid leukemia is one of the most well-known types of leukemia. Inflammation is one of the leading causes of cancer; therefore, anti-inflammatory agents are used for reducing and suppressing the growth of cancer cells. Dexamethasone, a cortisol agonist, has anti-inflammatory, anti-tumor, and apoptotic effects. Diclofenac is a cyclooxygenase enzyme inhibitor with anti-inflammatory properties. This study was performed to determine the synergistic effect of diclofenac and dexamethasone on the growth of K562 cancer cells.

In this descriptive-analytical study, K562 cell line was cultured in RPMI-1640 medium enriched with glutamine, penicillin, and streptomycin. The cytotoxic effects of dexamethasone, diclofenac and their combination (multi-target tracking) were evaluated using MTT assay. Hoechst staining and DNA electrophoresis were carried out to evaluate the occurrence of apoptosis.

Diclofenac, dexamethasone and their combination had cytotoxic effects on the cells at concentrations of 20, 40, 60, and 80 µmol/ml. A significant cytotoxic effect was observed after 72 hours of treatment with different concentrations of the drugs (P<0.05). Hoechst staining showed that DNA fragmentation was increased in the treated cells. DNA electrophoresis also showed induction of apoptosis by diclofenac, dexamethasone, and their combination.

The combination of diclofenac and dexamethasone at concentration of 20 µmol/ml is more effective in inducing apoptosis in K562 cells compared with each drug alone.