These signals feed into mechanistic target of rapamycin (mTOR), which, in the context of hypoxia, leads to the rapid suppression of protein synthesis,11 presumably in order to conserve energy.12 Levels of hypoxia vary between and within tumours, correlate with patient outcomes, and can lead to differences in response to therapy.13 A better understanding of heterogeneity in hypoxia-driven changes in gene expression will therefore inform strategies for precision medicine,14 raising the need for reliable biomarkers of tumour hypoxia. This evidence concerns the gene MTOR and neoplasm.