PTK2 and neoplasm: In conclusion, the different classes of polyphenols act in the tumor area on multiple intracellular proteins involved in focal adhesion plate turnover by inhibiting phosphorylation upstream of the FAK protein and preventing its activation, as well as by inhibiting the activation of downstream proteins, such as ERK and Akt, thus causing a blockade of signal transduction pathways involved in cell survival and migration (Table 1).