Evaluation of apoptosis induced by COX-2 inhibitors in leukemia and breast cancer cells

Recently, leukemia and breast cancers consider as the main reasons of death. Apoptosis as one of the therapeutic mechanism has favorable applications in cancer. The knowledge of how apoptotic pathways are deregulated in cancer is crucial to development of effective anti-cancer treatments. There is growing evidence indicating COX-2 inhibitors have anti-cancer activity. In this study, the ability of two new synthesized COX-2 inhibitors to induce apoptosis was evaluated by Annexin-V/PI analysis and then in order to show its upstream mechanism, we determined the expression of NF-kB, FHC and Egr-1 factors.

MCF-7 and K562 cells were cultured and treated by two compounds (1, 2) at their IC50 concentrations for 16 h and analyzed by Annexin-V-FLUOS labelling solution. The whole cell lysate was prepared to evaluate NF-kB by Trans AM kit. Egr-1 and FHC expressions were determined using western blotting.

The flowcytometric findings demonstrated the apoptotic effect induced by compound 1 in MCF-7 and compound 2 in K562 cells. In addition, the results of NF B assay showed that compound 1 and 2 could considerably diminish the NF B transcription factor in both cell lines. Our experiment also revealed the significant reduction in Egr-1 and FHC expressions after treatment of MCF-7 cells with compound 1compared with control cells, while only FHC was suppressed in the compound 2-K562 treated cells.

We suggest that compound 1 can induce apoptosis via reduction of NF B/FHC and Egr-1 in MCF- 7 cells, whereas compound 2 triggers apoptosis through NF B/FHC pathway.