Cure for cancer may live in our intestines

Digest this! Researchers have discovered a biological mechanism that can allow cancer patients to tolerate lethal doses of chemotherapy and radiotherapy by protecting their gastrointestinal tracts.
Too much chemotherapy and radiation is harmful and kills the patient before it kills the tumour, researchers said.
However, if the patient's gastrointestinal tract remains healthy and functioning, the patient's chances of survival increase exponentially, said Jian-Guo Geng, associate professor at the University of Michigan School of Dentistry.
Recently, Geng's lab discovered a biological mechanism that preserves the gastrointestinal tracts in mice who were delivered lethal doses of chemotherapy.
The findings, published in the journal Nature, could revolutionise cancer therapy, Geng said.

"It's our belief that this could eventually cure later-staged metastasised cancer. People will not die from cancer, if our prediction is true," said Geng, who emphasised that the findings had not yet been proven in humans.

"All tumours from different tissues and organs can be killed by high doses of chemotherapy and radiation, but the current challenge for treating the later-staged metastasised cancer is that you actually kill the patient before you kill the tumour.
"Now you have a way to make a patient tolerate to lethal doses of chemotherapy and radiotherapy. In this way, the later-staged, metastasised cancer can be eradicated by increased doses of chemotherapy and radiation," said Geng.

Geng's lab found that when certain proteins bind with a specific molecule, it revs intestinal stem cells into overdrive for intestinal regeneration and repair.
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 tumours.
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, Geng said.

These factors could give the patient just enough of an extra edge to survive the stronger doses of chemotherapy and radiation, until the tumour or tumours are eradicated.
In the study, 50-to-75 per cent of the mice treated with the molecule survived lethal doses of chemotherapy. All of the mice that did not receive the molecule died, Geng said.
"If you can keep the gut going, you can keep the patient going longer. Now we have found a way to protect the intestine. The next step is to aim for a 100-per cent survival rate in mice who are injected with the molecules and receive lethal doses of chemotherapy and radiation," Geng said.