Cancer is a highly heterogeneous pathology related to defects in regulatory circuits that govern cell homeostasis including cell death, proliferation , differentiation and migration. Flavonoids can affect the overall process of carcinogenesis by several mechanisms, including antioxidant activities , the scavenging effect on activated mutagens and carcinogens , interaction with proteins that control cell cycle progression depending on p53 , apoptosis induction by activation of caspase-9 and caspase-3 , and general inhibitors of cytokine-induced gene expression (Table 1).For instance, EGCG, the major catechin in tea, has been largely studied compared to other tea compounds in many epidemiological studies. EGCG induces a pronounced and specific growth-inhibitory effect on breast cancer cells, but not on their normal counterparts.