Tumors have stem cells. As in people, these immature, undifferentiated cells have the potential to perform any function within the tumor. Now researchers are using their understanding of how cancer stem cells are able to regenerate to help stop colon cancer in its tracks.
Colon cancer is the third leading cause of cancer deaths in the developed world, and second in the U.S. It strikes 140,000 Americans each year and is responsible for at least 500,000 fatalities. Although hereditary factors can increase someone’s cancer risk, the majority of colon cancer cases occur in patients with no family history of the disease. Moreover, there are often no initial symptoms, meaning people at risk need to be screened regularly to catch the disease when it is still likely to respond well to treatment.
African Americans and people over 50 are particularly prone to colon cancer. Other risk factors include inflammatory bowel disease or diabetes, as well as smoking or excessive alcohol use. It is possible to lower one’s colon cancer risk by living an active lifestyle, eating a low-fat, high-fiber diet, and taking steps to prevent obesity.
The flexibility of stem cells, which makes stem cell treatments and therapy such a promising research area in humans, causes problems for doctors and patients fighting cancer. Tumor stem cells can make it possible for a tumor to grow back even after being almost completely destroyed.
Current treatments for colon cancer generally involve surgery. In the very early stages, when it might be localized in a single polyp, the polyp can be excised in the course of a colonoscopy as soon as it is found. When it’s larger, but still fairly small, laparoscopic surgery through a very small incision can be used to remove it. If the cancer has begun to spread, chemotherapy or radiation therapy—or a combination of the two—may be needed.
The new approach targets the gene responsible for the stem cells’ resilience. By inhibiting this gene, doctors hope to prevent cells from regenerating. In experiments in laboratory animals, researchers were able to completely shut down cancer growth, and permanently keep it from coming back.