In Vitro Sensitivity of Leukemia Cells to Propranolol

BACKGROUND: Propranolol, as a beta-adrenergic blocker is used for treatment of a large number of cardiovascular diseases such as hypertension and arrhythmias. The inhibitory effects of propranolol on tumor cells growth and also its cytotoxicity on cancerous cells have been revealed by several studies. In this study the sensitivity of a number of human leukemic cell lines to propranolol was evaluated in vitro. METHODS: Two human leukemic T cells (Molt-4 and Jurkat) and a monocyte (U937) cell line were used in this study. The cells were cultured in complete RPMI medium and then incubated with different concentrations of propranolol (0.0004 -0.4 mM) in the presence or absence of phytoheamagglutinin (20 μg/ml) for 12, 24 and 48 hours. The cytotoxic effect of the drug was then assessed by trypan blue dye exclusion and also 3-(4,5-dimethyl thiazol-2,5-diphenyltetrazoliumbromide) (MTT) reduction methods. RESULTS: Propranolol induced a significant dose dependent cytotoxic effect at ≥ 0.2 mM concentration on all three human cell lines (Molt-4, Jurkat and U937) used in this study, after 12 hours incubation onwards, compared to untreated control cells. CONCLUSIONS: Our results demonstrated that leukemic cell lines used in this study were sensitive to propranolol at ≥ 0.2 mM concentration of the drug. These results suggest that propranolol may have potential implication in chemoprevention of lymphoproliferative disorders along with its chronic long-term usage in cardiac problems.