Cancer is a systemic disease that is associated with host metabolic changes, including obesity, diabetes, and cachexia/muscle wasting syndrome, each of which alters the host’s metabolic and nutritional environment. Cancer cells actively acquire nutrients from the extracellular space to support their growth, but how they sense and respond to changes in systemic nutrient availability remains incompletely understood. To explore host-tumour metabolic and nutritional interactions, we use the fruit fly Drosophila melanogaster as a model system. Our studies have started to uncover how tumours modulate the expression of SLC transporters to respond to systemic metabolic changes. These findings provide insight into the mechanisms by which tumours adapt to changes in nutrient availability and offer a potential therapeutic strategy to target transporters for cancer treatment.