Plant natural products including alkaloids, polyphenols, terpenoids and flavonoids have been reported to exert anticancer activity by targeting various metabolic pathways. The biological pathways regulated by plant products can serve as novel drug targets. Plant natural compounds or their derivatives used for cancer treatment and some novel plant-based compounds which are used in clinical trials were discussed. Callus suspension culture with secondary metabolites can provide a continuous source of plant pharmaceuticals without time and space limitations. Previous research has shown that rice callus suspension culture can kill > 95％ cancer cells with no significant effect on the growth of normal cells. The role of candidate genes and metabolites which are likely to be involved in the process and their potential to serve as anticancer and anti-inflammatory agents were discussed. Large scale production of plant callus suspension culture and its constituents can be achieved using elicitors which enhance specific secondary metabolites combined with bioprocess technology.