Niamh McCallum

Disulfiram (DSF), a well-known anti-alcoholism drug, exhibits potent anticancer activity via its metabolite, diethyldithiocarbamate (DDC), which forms a cytotoxic copper complex that selectively targets cancer stem cells. However, its clinical utility is limited by poor solubility and rapid plasma metabolism. This study explores saccharide-linked DDCs as novel prodrugs designed to enhance stability, solubility, and tumour-selective activation. These compounds feature thioglycosidic bonds that shield the DDC moiety from premature degradation while retaining its metal-chelating function to form the active copper(II)bis(N,N-diethyldithiocarbamate) (Cu(DDC)₂) complex. The synthesised derivatives were characterised and evaluated for serum stability and in vitro cytotoxicity across several cancer cell lines, including colorectal, breast, lung, and brain cancers. Copper-complexed saccharide-DDC prodrugs demonstrated remarkable cytotoxicity, with improved biostability and solubility profiles. These findings highlight the potential of saccharide-linked DDCs as stable, copper-activated prodrugs for cancer therapy. Further in vivo studies are warranted to validate their pharmacokinetics and clinical relevance.

A major hallmark of cancer is the reprogramming of cellular metabolism from oxidative phosphorylation (OXPHOS) to glycolysis, a phenomenon known as the Warburg effect. To sustain high rates of glycolysis, cancer cells overexpress GLUT transporters and glycolytic enzymes, allowing for the enhanced uptake and consumption of glucose. The Warburg effect may be exploited in the treatment of cancer; certain epimers and derivatives of glucose can enter cancer cells and inhibit glycolytic enzymes, stunting metabolism and causing cell death. These include common dietary monosaccharides (ᴅ-mannose, ᴅ-galactose, ᴅ-glucosamine, ʟ-fucose), as well as some rare monosaccharides (xylitol, ᴅ-allose, ʟ-sorbose, ʟ-rhamnose). This article reviews the literature on these sugars in in vitro and in vivo models of cancer, discussing their mechanisms of cytotoxicity. In addition to this, the anticancer potential of some synthetically modified monosaccharides, such as 2-deoxy-ᴅ-glucose and its acetylated and halogenated derivatives, is reviewed. Further, this article reviews how certain monosaccharides can be used in combination with anticancer drugs to potentiate conventional chemotherapies and to help overcome chemoresistance. Finally, the limitations of administering two separate agents, a sugar and a chemotherapeutic drug, are discussed. The potential of the glycoconjugation of classical or repurposed chemotherapy drugs as a solution to these limitations is reviewed.