This was supplemented by analysis of additional genes associated with the pentose phosphate pathway (Supplementary Figure 5a) and glucose metabolism (Supplementary Figure 5b).27 We found that there was upregulation of glycolysis genes (HK1, PFKM, PKM2, LDHA significantly upregulated) in HPV−ve HNSCC, which also expressed lower levels of the negative regulator, PDK1 (Fig. 2). This evidence concerns the gene PKM and head and neck squamous cell carcinoma.