Alpha fetoprotein (AFP) is a highly expressed
protein during
fetal development. It’ s a shuttle
protein that transports
nutrients to embryonic
cells. Similarly, during the development of malignant
tumors such as
liver cancer,
tumor cells also express high levels of AFP and its receptors. They uptake AFP and its delivered substances through AFP receptors. Therefore, AFP can be combined with anticancer
drugs to attack
tumor cells selectively. There are several ways of AFP to deliver
drugs, which can be noncovalently bound with
drugs, and the
drugs are wrapped in the hydrophobic pocket of AFP; they can also combine with
drugs through covalent bonds, or use AFP to connect with
nanoparticles and
liposomes to improve the effect of
drug delivery. AFP delivered
drugs can be effectively released in the low
pH environment of
cancer cells. In order to avoid the
risk of AFP
carcinogenesis,
drugs can be delivered by modifying AFP or using AFP fragments. Because AFP delivered
drugs targeting
therapy mainly attacks
cancer cells that expressed AFP receptor, it has little effect on normal
cells. AFP delivred
drugs can not only promote the
absorption of
drugs by
tumor cells, enhance the anti-
cancer activity of
drugs, but also overcome the problem of
multidrug resistance (MDR). In addition, studies have found that AFP delivered
drugs also have the effect of
immunotherapy. AFP delivered
drugs can not only activate
T cell receptors, eliminate
immune tolerance and inhibit
tumor growth, but also inhibit
myeloid derived suppressor cells (
MDSCs), activate
NK cells and
T cells, thus destroying
cancer cells and preventing
cancer stem cell metastasis. Therefore, AFP delivery of
drug is a new
therapy combining
immunotherapy and targeted
chemotherapy, and it may become a strategy for
cancer treatment in the
future.