EGFR and cancer: In human CRC cells, simultaneous and sustained activation of several RTKs (i.e. EGFR, PDGFRα, PDGFRβ and FGFR) shall induce persistent activation of downstream cascades, including PI3K-Akt and Erk-MAPK signalings, which work in a coordinated fashion to promote cancer cell growth, survival, and angiogenesis as well as invasion/migration and apoptosis/death resistances [18].