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Aim and Background:
Recent studies show that the depletion of naturally occurring deuterium can result in tumor regression in both in vitro and in vivo models. The purpose of this study was to investigate the effect of deuterium depleted water (DDW) discretely and in combination with 5-FU on cell growth and anti-oxidant system of breast cancer cells.
Mateial and Methods:
The cellular cytotoxicity test was performed using MTT assay.  The MCF-7 cells were treated with decreasing deuterium concentrations of DDW alone, 5-FU alone and both. The malondialdehyde (MDA) level and the catalase (CAT) and superoxide dismutase (SOD) enzyme activities were identified spectrophometrically. One way analysis of variance (ANOVA) and t- test were used for statistical analysis. P ≤ 0.05 was considered significant.
Results: Treatment the cells with different concentrations of DDW alone especially in concentrations of 100 and 125ppm imposed growth inhibitory effect on MCF-7 cells. Also, 5-FU alone significantly decreased the survival fractions of MCF-7 cells and DDW in combination with 5-FU augmented 5-FU inhibitory effects on the cells. Compared to the control group (150 ppm), it was observed that in the cells treated with Lower concentrations of DDW, the activities of catalase and superoxide dismutase enzymes increased, but the level of malonyldialdehyde decreased.
Conclusion: Deuterium depleted water can be considered as an adjuvant in anticancer drugs.