A new study has challenged the fact that a widely known human protein that was previously thought to help fight cancer can even boost the tumor growth too.
Scientists from University of California San Diego have carried out a new study challenging the description of the human protein ‘p53’ that is renowned for its cancer-fighting abilities, leading to its popular title as ‘the guardian of the genome’.
“The widely accepted idea is that p53 suppresses cancer, but in our study we would argue against that. In some cancers it would have the opposite effect by promoting cancer,” said researcher Yang Xu.
Studying the ‘wild type’ version of p53 – WTp53 – that is present widely in nature, the team found evidences that in some cases, the protein instead promotes tumors rather than suppressing them.
The finding explains the established enigma that though p53 is mutated in over 50% of all human cancers, it is not frequently mutated in some cancers such as liver cancer.
Over four years research on liver cancer showed that WTp53 stimulates tumor growth by enhancing cancer metabolism. The key, as the researchers explain, is a protein called PUMA, which works inside the energy hub of cells the mitochondria.
They found that at appropriate levels, PUMA disrupts normal function of mitochondria and causes a switch from oxidative phosphorylation process for efficient energy production in cells to glycolysis alternative energy path that helps boost cancer metabolism.
Xu notified that the research provides a warning for cancer drug discovery. Drug therapies designed to improve p53’s function in cancer patient might be inadvertently causing an opposite effect.