Re: Does Oxygen kill cancer and how does it do it?

Oxygen is a very reactive element: it is a very strong electron acceptor 
(oxidizing agent), and will "pull" electrons away from many molecules, thus, 
oxidizing them. Although this is beneficial for aerobic organisms that use 
oxygen as a final electron acceptor in the electron transport chain to 
produce ATP (energy), it can produce several toxic "Reactive Oxygen Species" 
(ROS) that can have a wide range of damaging effects on cellular structures.  
Two common toxic molecules that are produced, superoxide anion and Nitric 
Oxide (NO), can cause oxidative damage to enzymes and DNA. 
Cancer is believed to be caused by an accumulation of strategic DNA 
mutations that lead to changes in cellular processes such as: misregulated 
cell growth and proliferation, changes in cell shape and structure and 
inhibition of a cell suicide mechanism called Apoptosis.
Becuase oxygen species can react and alter DNA leading to random mutations, 
increases in oxygen levels, therefore, could increase the amount of ROS 
present in the cell while increasing the chances of acquiring DNA mutations 
in processes that lead to cancer.
One potential benefit of oxygen treatment could be that increases in oxygen 
will decrease angiogenesis - the growth of blood vessels.  Tumors, in 
general, require elevated levels of oxygen and nutrients in blood in order 
to sustain elevated growth rates.  If oxygen treatment reduces angiogenesis, 
then this could potentially slow the growth of a tumor.
I hope this helps!
Sincerely,
Elena Rodriguez