In contrast to wild-type BT-20 cells, PEG engagerEGFR did not enhance the anti-proliferation activity of Doxisome in BT-20/shEGFR cancer cells (BT-20 cells treated with short hairpin RNA to knockdown the expression of EGFR) as compared with drug-loaded nanocarrier alone or drug-loaded nanocarrier plus PEG engagerCD19 (Supplementary Fig. 6), further showing that PEG engagerEGFR mediates endocytosis of PEGylated nanocarriers via the EGFR internalization pathway. This evidence concerns the gene EGFR and cancer.