Oxygen Radicals May Protect Against Cancer, Researchers Investigate

May, 2021 - By SMI

Researchers derive new observations with reference to reactive oxygen species and cancer development.

Oxygen radicals refers to the reactive oxygen species or ROS. These oxygen radicals serve as a crucial part in the human system. The ROS has positive and negative effects to the human body. For example, ROS is produced in the body during smoking or during exposure to UV radiation. Since they are highly reactive, they can easily damage various parts of a cell including DNA. In turn there is a risk of inflammatory responses in the body and the affected cells may degenerate into cancer cells. ROS are also produced in the human body at relatively high concentrations, while destroying the invading bacteria or viruses, for which the ROS are released by immune cells or lung epithelial cells.

ROS also acts as signaling molecules in the human body, in low concentrations. During this process, the ROS are produced by specific enzymes called Nox4, which produces small amounts of hydrogen peroxide (H2O2). These Nox4 enzymes are found in all body cells, where its product hydrogen peroxide aids in maintaining many specialized signaling functions such as signaling functions related to the inhibition of inflammatory reactions. A study led by Professor Katrin Schroder at Goethe University Frankfurt stated that by producing Hydrogen peroxide, Nox4 can help in preventing cancer development.

Their investigation witnessed positive outcomes, when the experimentation on mice showed that the mice were unable to produce Nox4 enzymes following a genetic mutation. These mice were also observed to be exposed to a carcinogen due to which their risk of developing a tumor developed. Researchers’ molecular investigation indicated that the hydrogen peroxide formed by Nox4 enzyme helps in the formation of a cascade that helps in preventing essential signaling proteins to enter a cell’s nucleus. They concluded that if Nox4 enzyme and thus hydrogen peroxide is absent, the signaling proteins enter the cells’ nucleus, and it leads the cells to ignore the DNA damage in a cell, which further triggers cancer formation. The small amount of H2O2 is thus responsible for maintaining hormesis in the cell.