EGFR and neoplasm: They showed that erlotinib synergistically inhibited tumor cell growth in an erlotinib pre-treatment group, whereas the docetaxel pre-treatment group experienced no synergistic effect, suggesting that EGFR-TKI used before the cytotoxic drug had a synergistic effect on inhibition of tumor cell growth, but not thereafter in a MDA1986 cell line [31].