doi:10.1038/nindia.2012.83 Published online 4 June 2012
Researchers report a new approach to shrink cancerous breast tumours with pure oxygen.
Mice carrying breast tumors when subjected to 30% pure oxygen showed significant reduction of tumor (64%) in 2-3 days without any side effects. The researchers say this is a significant considering that the widely used tumour drug cisplatin failed to show any result in shrinking hypoxic tumours.
Hypoxic tumors contain a core that is deprived of oxygen. The researchers have, for the first time, measured the oxygen concentration to be 1.8 % in the core of breast tumors (against 21.8% in normal cells). Repeated oxygenation at normal atmospheric pressure resulted in an eight-fold increase in cell death and significant regression of tumour in the mice without any adverse effect.
The scientists from New-Delhi based Jawaharlal Nehru University (JNU) have found that the re-oxygenation activates the tumour suppressor protein p53, which remains 'non-functional' in the hypoxic core because of lack of oxygen. Oxygen therapy without pressure, as opposed to hyperbaric oxygen therapy, may be ideal for hypoxic tumour regression, they conclude. The discovery might have far reaching consequences in translational research.
The authors of this work are from: School of Biotechnology, Jawaharlal Nehru University, New Delhi, India and Davis Heart and Lung Research Institute, The Ohio State University, Columbus, Ohio, USA.