Lactoferrin (LF) is a glycoprotein of the transferrin (TF) family that can bind to TF receptors (TFRs) and LF membrane internalization receptors (LFRs) that are highly expressed on the surface of cancer cells and blood-brain barrier (BBB), thereby promoting entry into the cell nucleus (Agwa and Sabra, 2021). Here, TF is linked to cancer.