Global Journal of Medical Research, F: Diseases, Volume 23 Issue 2

9 Year 2023 Global Journal of Medical Research Volume XXIII Issue II Version I ( D ) F © 2023 Global Journals A Cancer Prevention and Treatment Opportunity Figure 2: AFP/AFPR shuttle delivery system. A: AFP delivers nutrients to AFPR-positive cells. B: AFP delivers toxins. Abbreviations: AFP – alpha-fetoprotein, DHA – docosahexaenoic acid, MDSC – myeloid-derived suppressor cell, – AFP secretion is unknown. example, the myelination of nerve fibers in the fast- growing embryo’s brain. Embryo cells and normal and malignant peripheral monocytes/macrophages use the autocrine AFP/AFPR system for nutrient supply (Fig. 2, A) [25]. Low-differentiated lymphocytes use AFPR during blast transformation [26]. Monocytes/ macrophages have specific 62 and 65 kDa AFP-binding receptors, which are involved in the physiological regulation of the immune response [27]. Unlike AFP, many cancers express AFPR [28], which should be considered the tumor marker and oncofetal protein #1. The AFP gene-knockout rodent models have demonstrated that AFP is not obligatory for full-term delivery [29]. The AFPR gene and structure are unknown yet to perform the gene-knockout experiment. In any case, the AFP/AFPR duo is vital for the embryo (and cancer). The fact that the mother is tolerable to the embryo for nine months demonstrates that from the very beginning, AFP (Fig. 1) delivers nutrients to MDSCs, “corrupting” them to generate a protective shield over an embryo. MDSCs suppress NK cells which are “spontaneous cytotoxic cells” involved in surveillance against tumor cells. NK cells attack “aliens,” low differentiated embryos, stem, cancer cells, and CSCs [30, 31]. NK cells can erase cancer at the earlier stages and solve the urgent problem of metastases. II. I njectable A fp-toxins In cancer, MDSCs are “corrupted” also [32]. The effective way to ruin corruption is to eliminate the head. For this purpose, instead of DHA, AFP can deliver toxins to MDSCs (Fig. 2, B). The MDSCs death unleashes NK cells, and the whole immune system, enabling it to recognize and attack cancer the way it does other diseases. In addition, AFP-toxin kills AFPR- positive cancer cells and possibly CSCs (Fig. 2, B). Like AFP-DHA, AFP complexes with hydrophobic/amphiphilic toxins hidden in the hydrophobic cavity are stable in the bloodstream. They release the toxin only inside the AFPR-positive cells.