Inhibition of ErbB receptors, Hedgehog and NF-kappaB signaling by polyphenols in cancer

Carcinogenesis is a multi-step process triggered by cumulative genetic alterations, which drive the progressive transformation of a normal cell into a cancer cell. Among the signal transduction pathways whose crosstalk plays an important role in neoplastic transformation are those mediated by ErbB receptors, NF-kappaB and the Hedgehog (HH)/glioma-associated oncogene (GLI) cascade. Polyphenols can be employed to inhibit the growth of cancer cells due to their ability to modulate the activity of multiple targets involved in carcinogenesis through simultaneous direct interaction or modulation of gene expression. This review will describe the cross-talk between ErbB receptors, NF-kappaB and the Hedgehog (HH)/glioma-associated oncogene (GLI) signaling pathways and the potential role of polyphenols in inhibiting this dialogue and the growth of cancer cells.