April 2, 2009

Certain molecules may be cancer biomarkers

U.S. bioengineers say excess amounts of a naturally fluorescent molecule -- NADA -- might serve as a natural biomarker for cancer.

Pennsylvania State University researchers said NADA (nicotinamide adenine dinucleotide) is a coenzyme -- a non-protein molecule necessary for the functioning of an enzyme -- found mostly in the inner membrane of a cell's mitochondria. It fuels a series of biochemical reactions that involve various enzymes to produce ATP, the major energy source in cells.

But Associate Professor Ahmed Heikal said in the case of disease or metabolic disorder, the enzymes and their related reactions can become disabled, causing a buildup of unused NADH.

Dysfunctional enzymes in the mitochondria are known to be associated with serious health problems such as cancer and neurodegenerative diseases, said Heikal, who led the study. By detecting the level of NADH and its distribution inside living cells, we should be able to monitor the mitochondrial activity and thus the integrity of any given cell, without adding potentially toxic dyes or actually destroying the cell.

The research is reported in the Journal of Photochemistry and Photobiology B.