The human diet contains, in addition to a great variety of natural carcinogens, many inhibitors of experimental
carcinogenesis, including antioxidants, retinoids, flavones, aromatic isocyanates, coumarin, indoles and
selenium. Epidemiological evidence from different geographical locations and dietary customs suggests that
such food constituents play an important modulatory role in human cancer incidences. In vivo screening tests
for several organs including liver, stomach, lung and urinary bladder based on qualitative putative preneoplastic
changes have been developed. We tested modifying effects of Korean traditional food such as red pepper, garlic,
cabbage and their principal constituents capsaicin, dially sulfide(DAS) and indole-3-carbinol(I3C) on various
experimental animal carcinogenesis models. Capsaicin showed inhibition on the mouse lung tumor induced by
benzo(?)pyrene or dimethylbenzanthracene and on rat lung tumor induced by combined treatment of
diethylnitrosamine(DEN), methylnitrosourea(MNU), dibuthylnitrosamine(DBN). But it showed significant
promotional effect on rat hepatocarcinogenesis induced by DEN and on rat urinary bladder tumor induced by
DEN, MNU and DBN. Garlic extract and DAS showed inhibition on DEN-induced hepatocarcinogenesis. DAS also
showed significant inhibition on N-methyl-N'-nitro-N- nitrosoguanidine(MNNG)-induced gastric carcinogenesis
and on tumor development of liver, lung, thyroid, urinary bladder induced by DEN, MNU and DBN. Cabbage
extract showed inhibition on DEN- induced hepatocarcinogenesis. I3C showed inhibition on MNNG-induced
gastric carcinogenesis, but it showed promotional effect on the postinitiation stage as well as an inhibitory effect
on the preinitiation stage on DEN-induced hepatocarcinogenesis. Those results suggest that components of
Korean traditional food contain many modifying factors on carcinogenesis and play an important role in
Korean-specific cancer incidence. Further research would be required to understand the underlying mechanisms
for such modifying effects.

Keywords: Red pepper, Garlic, Cabbage, Capsaicin, Diallyl sulfide, Indole-3-carbinol, Carcinogenesis,
Animal