Effect of allicin and its analogs on cytotoxicity and radiosensitization of hypoxic cells

In our search for new radiosensitizers, the author studied the effects of allicin, the active principle of garlic on cytotoxicity and radiosentization of Chinese hamster (V-79) cells. Allicin was synthesized by the oxidation of diallyl disulfide with hydrogen peroxide. At 10 μm concentration allicin inhibited the colony formation of V-79 cells by 50% upon 2 hr exposure under aerobic and hypoxic conditions. Diallyl sulfoxide (DSO) an analog of allicin required 1 mM concentration and 5 hr exposure to achieve a similar degree of inhibition of growth. Diallyl sulfide, however had no effect on inhibition of growth up to a concentration of 1 mM. The results of pharmacokinetic studies suggest that DSO is a new class of hypoxic cell radiosensitizer that can achieve high therapeutic concentrations in solid tumors and may possess clinical potential