An article from Science Daily explains how the amount of cytochorme c oxidase (CcO) can help predict the life expectancy of people with the deadly brain tumor glioblastoma multiforme (GBM). Study results found 20-30% of GBM patents who have tumor cells with overactive CcO enzyme live half as long when compared to those with a less active enzyme. Higher levels of CcO generate more energy making the cancer cells less susceptible to chemotherapy.
The goal of temozolomide chemotherapy is to disrupt cancer cells from copying DNA. High activity of CcO cytochrome c is preoccupied with making energy instead of self-destructive signaling, keeping cancer cells alive. The lack of CcO makes the temozolomide more efficient in eliminating cancer cells and extending the life expectancy of patients. This article was cited from an article from PLOS ONE.