EGFR and cancer: As pointed out by Singh et al. [42], the potential for these cancer cells to become invasive is eradicated through the inhibition of EGFR. Wali et al. [23] have shown that the painting of the rat's oral cavity with polyethylene glycol-8000 using a sable brush for up to 3–4 minutes has significantly lowered the expression of EGFR in the 4NQO rats.