Anti-cancer potential of flavonoids: recent trends and future perspectives

Cancer is a major public health concern in both developed and developing countries. Several plant-derived anti-cancer agents including taxol, vinblastine, vincristine, the campothecin derivatives, topotecan, irinotecan and etoposide are in clinical use all over the world. Other promising anti-cancer agents include flavopiridol, roscovitine, combretastatin A-4, betulinic acid and silvestrol. From this list one can well imagine the predominance of polyphenols, flavonoids and their synthetic analogs in the treatment of ovarian, breast, cervical, pancreatic and prostate cancer. Flavonoids present in human diet comprise many polyphenolic secondary metabolites with broad-spectrum pharmacological activities including their potential role as anti-cancer agents. A positive correlation between flavonoids-rich diet (from vegetables and fruits) and lower risk of colon, prostate and breast cancers lead to a question that whether flavonoids mediate the protective effects as chemopreventive agents or can interact with different genes and proteins to play role in chemotherapy. The current review emphasizes onto the therapeutic potential of flavonoids and their synthetic analogs as anti-cancer agents by providing new insights into the factors, regulation and molecular mechanisms along with their significant protein interactions.