ATP5PB and neoplasm: However, compared to the down-regulations at the protein level, changes at mRNA levels seemed to be much less, and some genes even showed discordant changes, such as ATP5F1, NDUFA11 et al. Because the mitochondrial OXPHOS in GBM is intact in function, and OXPHOS still plays an essential role in tumorigenesis and tumor progression, we supposed that the dramatic proteomic alterations may result from combined various factors, such as oncogenes, tumor suppressors, and a hypoxic microenvironment [10].