CD320 Receptor and Vitamin B12 as Potential Targets for Anti-Cancer Therapy

Despite the development of a wide plethora of different anticancer agents, most of them are not used for patient treatment due to adverse effects caused by untargeted cytotoxicity. To prevent this unwanted toxicity, it is necessary to develop therapies discriminating between healthy and cancerous cells. One possible method is to target proteins overexpressed in cancer but not in normal cells. CD320 is a receptor responsible for the uptake of the transcobalamin-bound fraction of vitamin B12 (cobalamin), which is necessary for DNA synthesis, and thus, cell proliferation. CD320 was shown to be overexpressed in many cancers and its potential role as an early cancer biomarker was confirmed in several studies. Consequently, CD320 may represent a promising anti-cancer therapy target. This review summarizes the current advances and perspectives of anti-cancer CD320 targeting therapy, including therapeutic conjugates of vitamin B12, CD320-specific antibodies and nanobodies, nanoparticles loaded with cytotoxic drugs, porphyrin, and the potential of targeted CD320 therapy in attenuation of tumor tissues. Given the growing interest in CD320 as a novel target for anti-cancer therapy, further in vivo studies are required for the investigation of CD320 targeting effects on systemic cytotoxicity.