Evaluation of Proapoptotic Potential of Saraca asoca Flower Extract on Skin Cancer Cell Line

Background: Cancer persists as a major health issue globally due to its high rate of morbidity and mortality. Skin cancer is the most common cancer and accounts for at least 40% of cancer cases worldwide. Search for tumour-selective and novel anticancer compounds with lesser side effects remains a major focus of cancer research. Saraca asoca is a traditional Indian medicinal plant, known to have anti-cancer, anti-menorrhagic, anti-oxidant, anti-oxytocic and anti-microbial activities. Though phytoconstituents of the Saraca asoca leaves, bark, and flowers have been reported in few studies, the cytotoxic potential of Saraca asoca flowers has not been evaluated.

Aim: To evaluate the proapoptotic potential of Saraca asoca flower extract on skin cancer cell line.

Materials and Methods: In this present study, the cytotoxic potential of Saraca asoca flower extract (10 to 60μg/ml) was evaluated by MTT assays in B16-F10 skin cancer cells. According to the MTT assay, we determined the optimal doses (IC-50: 30µg/ml) which were used for further analyses. Analysis of changes in cell morphology is examined by a phase-contrast microscope. The impacts of Saraca asoca in B16-F10 cell death were also determined by AO/EtBr dual staining under a fluorescence microscope.

Results: In our study, the cell viability assay results showed that 50% of growth inhibition was observed at 30 μg/ml concentration of Saraca asoca flower extract treated B16-F10 cells, which has been taken as an inhibitory concentration (IC-50) dose value and fixed for further experiments. The morphological changes in B16-F10 skin cancer cell line with the treatment of Saraca asoca at 30 μg/mL for 24hrs has significantly altered the morphology of B16-F10 cell lines. AO/EtBr dual staining results showed the early apoptotic cells having bright orange areas of condensed or fragmented chromatin in the nucleus after Saraca asoca flower extract treated skin cancer cells.

Conclusion: The results of this present study showed that the flower extracts of Saraca asoca were cytotoxic and induced apoptosis to the cancer cells at a concentration of 30µg/ml at the 24th-time point.