Researchers at UT Southwestern published a study in the journal Nature Sunday identifying a cancer-specific metabolic pathway that fuels only the growth of certain kinds of kidney and adrenal tumors. This is a pretty remarkable finding, chiefly because if you can halt that specific metabolic process, you can kill the cancer cells without the damage to healthy cells usually associated with cytotoxic treatments like chemotherapy.
"The problem is usually what cancer cells do is use pathways similar to normal cells," lead researcher Dr. Ralph DeBerardinis tells Unfair Park. That's always been the rub -- you have to destroy normal cells along with the abnormal ones, causing digestive problems, hair loss and a host of other side effects.
At a molecular level, the Krebs cycle breaks fuel down into energy and the building blocks cells require for growth and division. In certain tumor cells, DeBerardinis and his colleagues found, a mutation causes the Krebs cycle to run in reverse, creating building blocks for growth but, they suspect, no energy. Because of this finding, treatments may be developed to target this reverse cycle fueling tumor growth in certain cancers without interrupting the processes of normal cells.
Now, determining which of the hundreds of thousands of chemical compounds will target the reverse pathway and starve the cancer cells to the exclusion of all others is the next step -- and it's easier said than done, to be sure. But DeBerardinis is optimistic, both for the prospects of identifying the right compound and for a potentially broader application for targeting the metabolic process.
Published simultaneously in Nature was a Massachusetts Institute of Technology study that found tumors often use an alternate metabolic pathway because many of the cancer cells receive an inadequate blood supply and are oxygen-starved. Like DeBerardinis, they suspect that a tumor's energy supply can be eliminated by disrupting the alternate metabolic process.
