Recent Advances in the Development of Metal-Glycoconjugates for Medicinal Applications

Rapidly proliferating tumor cells exhibit elevated demands for nutrients and energy to support their uncontrolled growth, with glucose serving as a key metabolic substrate. Glucose is transported into cells via facilitated diffusion mediated by glucose transporters (GLUTs), after which it undergoes a series of enzymatic reactions to generate energy. To accommodate their heightened metabolic needs, cancer cells frequently overexpress GLUTs, thereby enhancing glucose uptake. Notably, aerobic glycolysis-commonly referred to as the "Warburg effect"-has been identified as the predominant pathway of glucose metabolism within tumor tissues, even in the presence of adequate oxygen levels. Consequently, the conjugation of chemotherapeutic agents, including metallodrugs, to glucose-mimicking substrates holds significant potential for achieving tumor-specific intracellular drug delivery by exploiting the elevated glucose uptake characteristic of cancer cells. Moreover, in recent years, glycosylation of metal scaffolds has been extended to the development of bioactive metallodrugs for applications other than cancer treatment, such as potential tumor imaging, antiviral, antimicrobial, antiparasitic and anti-neurodegenerative agents. Accordingly, major advancements in the design of metal-based glycoconjugates for medicinal applications are here summarized and critically discussed, focusing on related results and discoveries published subsequently to our previous (2015) review article on the topic.