Metabolism of isothiocyanates in individuals with positive and null GSTT1 and M1 genotypes after drinking watercress juice

GSTT1 and M1 genotypes are not likely to be involved in the rate of excretion of ITCs in watercress. The demonstrated differences in protection among subjects with the two genotypes are not likely due to differences in overall ITC excretion rates, however, excretion rates of ITCs other than PEITC need to be investigated. Other yet to be identified mechanism(s) may underlie the diet and gene interactions between dietary ITCs and GST genotypes in human cancer prevention. Further research is needed to evaluate the protective mechanisms of isothiocyanates against cancer.