Surviving Lethal Chemotherapy by Boosting Stem Cell Activity

Increasing chemotherapy tolerance, so as to allow greater harm to be caused to cancerous tumors while the patient still survives the treatment, is a strategy that will be eclipsed by the next generation of cancer therapies. They will target cancer cells and have few to no side effects, and will certainly not be a case of flooding the body with poisons that are just a little more toxic to cancer than to the rest of the patient's cells. So the discovery made by these researchers will, I think, be something that finds application in regenerative medicine instead: a way to greatly boost stem cell activity in specific tissues should have many uses.

Treating a cancerous tumor is like watering a houseplant with a fire hose - too much water kills the plant, just as too much chemotherapy and radiation kills the patient before it kills the tumor. However, if the patient's gastrointestinal tract remains healthy and functioning, the patient's chances of survival increase exponentially. Recently, [researchers] discovered a biological mechanism that preserves the gastrointestinal tracts in mice who were delivered lethal doses of chemotherapy.

"It's our belief that this could eventually cure later-staged metastasized cancer. People will not die from cancer, if our prediction is true. All tumors from different tissues and organs can be killed by high doses of chemotherapy and radiation, but the current challenge for treating the later-staged metastasized cancer is that you actually kill the patient before you kill the tumor."

[Researchers] found that when certain proteins bind with a specific molecule on intestinal stem cells, it revs intestinal stem cells into overdrive for intestinal regeneration and repair. [Researchers have] worked with these molecules, called R-spondin1 and Slit2, for more than a decade. In the study, 50-to-75 percent of the mice treated with the molecule survived otherwise lethal doses of chemotherapy. All of the mice that did not receive the molecule died. "The next step is to aim for a 100-percent survival rate in mice who are injected with the molecules and receive lethal doses of chemotherapy and radiation."

Stem cells naturally heal damaged organs and tissues, but so-called "normal" amounts of stem cells in the intestine simply cannot keep up with the wreckage left behind by the lethal doses of chemotherapy and radiation required to successfully treat late-stage tumors. However, the phalanx of extra stem cells protect the intestine and gastrointestinal tract, which means the patient can ingest nutrients, the body can perform other critical functions and the bacterial toxins in the intestine are prevented from entering the blood circulation.

Link: http://www.sciencedaily.com/releases/2013/07/130731133155.htm