Fig. 7: OTUB1 facilitates hypoxia adaptation.

A–D Comparison of GLUT1 (A), PDK1 (B), LDHA (C) and OTUB1 (D) expressions in lung cancer tissues (n = 515) and in the adjacent normal tissues (n = 59). GLUT1 (A), PDK1 (B), LDHA (C) and OTUB1 (D) mRNA levels in tumors were higher than in normal tissues, as determined by the student’s t test. The data were obtained from the Cancer Genome Atlas (TCGA) data (https://cancergenome.nih.gov/) and analyzed by the online tool UALCAN (http://ualcan.path.uab.edu/). E Linear regression of OTUB1 and GLUT1 across the panels of normal and lung cancer samples described in A, D, was generated by the online analysis tool GEPIA (http://gepia.cancer-pku.cn/) based on TCGA data (https://cancergenome.nih.gov/). F Growth curves of WT or OTUB1-deficient H1299 (OTUB1^+/+ or OTUB1^−/−) cells (n = 5) cultured for the indicated days by CCK-8 assay. G, H Colony formation of WT or OTUB1-deficient H1299 (OTUB1^+/+ or OTUB1^−/−) cells (n = 3) cultured under hypoxia for the indicated days. I, J Oxygen consumption rate (OCR) changes in wildtype (WT) or OTUB1-deficient H1299 (OTUB1^+/+ or OTUB1^−/−) cells (n = 5) under normoxia (Nor) or hypoxia (Hyp) measured by Seahorse XFe24 Extracellular Flux Analyzer (I). Statistics of basal respiration, maximal respiration, and spare respiratory capacity were presented in J. K, L Proton efflux rate (PER) changes in WT or OTUB1-deficient H1299 (OTUB1^+/+ or OTUB1^−/−) cells (n = 5) under normoxia (Nor) or hypoxia (Hyp) measured by Seahorse XFe24 Extracellular Flux Analyzer. Statistics of basal glycolysis and compensatory glycolysis were presented in L. M–O Glucose uptake in WT or OTUB1-deficient H1299 (OTUB1^+/+ or OTUB1^−/−) cells (n = 3) under normoxia or hypoxia analyzed using fluorescent glucose analog 2-NBDG and detected by fluorescence microscopy (M), and flow cytometry analysis (N, O).