TF and cancer: Among these, transferrin receptor‐1 (TFR‐1 or CD71), a member of the TFR family, is able to form complexes with transferrin (TF) bound to Fe (III), whose internalization represents the most important way for cancer cells to absorb iron (Daniels, Delgado, Helguera, Penichet, & Tracy, 2006; Daniels, Delgado, Rodriguez, Helguera, & Penichet, 2006; Shen et al., 2018).