Purpose: The purpose of this work is to study the effect of green tea and grape seed extracts mixture (GTE-GSE mix) and γ-irradiation or their combination to enhance the antiproliferative effect on the growth of myeloma cells.
Method: Myeloma cell line SP2/OR was cultured in RPMI-1640 medium; total count and viability % were daily calculated. Myeloma cells (1 X 106/ml) were treated with GTE-GSE mix concentrations (100 - 1000 ng/ml), γ-irradiation doses (0.5 - 10 Gy) and their combination for 6 days. Evaluation of Caspase 8 and 9 activities were measured. Cell culture media and GTE-GSE mix activity was determined by DPPH method.
Results: The most effective dose of GTE-GSE mix on myeloma cells growth inhibition and viability % was 1000 ng/ml, while the effective dose of γ-irradiation was 8 Gy where viability percentage was zero. The obtained results indicated that treatment with GTE-GSE mix plus γ-irradiation combination (700 ng/ml + 6 Gy) resulted to zero% growth inhibition at 4th day. Treatment with combination dose induced activation of caspase 8 and caspase 9 levels more than GTE-GSE mix and γ-irradiation alone. Treatment with GTE-GSE mix and γ-irradiation individually resulted in significant reduction in DPPH activity to 62% while in combination treatment was 73.5%.
Conclusion: Treatment with GTE-GSE mix plus γ-irradiation (700 ng/ml + 6 Gy) combination resulted in marked increase of growth inhibition levels, apoptosis and cancer cells regression when compared with each agent alone. GTE-GSE mix plus γ-irradiation combination had an antiproliferative effect on the growth of myeloma cells.