Differences in the gut microbiome may explain why certain cancer drugs don’t work in all patients.
Filipe Cabreiro of University College London and his colleagues fed the nematode Caenorhabditis elegans different strains of the common gut bacterium Escherichia coli, and then looked at how much of a widely used cancer drug, 5-fluorouracil, was needed to prevent the worms’ eggs from hatching. They found that different strains of E. coli had varying effects on the drug’s efficacy in hindering DNA synthesis and cell division. In the worms where only low doses of the drug were needed, the bacteria expressed key genes involved in metabolizing 5-fluorouracil into products that damage RNA or increase DNA damage in the worms.
Bacteria that express these genes in the human gut could boost drug efficacy in cancer patients.