TFRC and cancer: For this purpose, the engineered ferritin was the humanized Archaeoglobus fulgidus ferritin (HumAfFt) characterized by the peculiar salt-triggered assembly-disassembly of the hyperthermophile Archaeoglobus fulgidus ferritin and which is successfully endowed with the human H homopolymer recognition sequence by the transferrin receptor (TfR1 or CD71), overexpressed in many cancer cells in response to the increased demand of iron.