TF and cancer: Numerous types of anti-cancer drugs targeted TfR1 have been developed, such as a variety of anti-TfR antibodies (HB21, 454A12, B3/25, OKT9, 7D3, 7579 and 42/6) (Daniels et al., 2012), and multiple tumor-targeting ligands which are responsible for the delivery of numerous antitumour cytotoxics (TF-doxorubicin, TF-cisplatin, TF-chlorambucil, TF-ricin A chain and TF-diptheria toxin) (Torti and Torti, 2013).