Through these studies, we also demonstrated that a standard fluorescence microscope along with proper imaging processing software (CellProfiler) can provide flow cytometry–like single-cell level analysis of HIF-1α-mediated metabolic changes in the radioresistant HNSCC cells, but in a more efficient, cost-effective, and non-destructive manner. This evidence concerns the gene HIF1A and head and neck squamous cell carcinoma.