AK4 and neoplasm: Interestingly, this AK4 co-expression network contained many hypoxia response element-containing HIF-1 signaling readouts scattered throughout different LUAD tumor stages, including: ALDOA (r > 0.4), ANGPT1 (r < −0.3), ENO1 (r > 0.4), GAPDH (r > 0.3), LDHA (r > 0.3), PDK1 (r > 0.4), SLC2A1 (r > 0.3), and TRFC (r > 0.3) (Supplementary Table S3).