Nearly 700,000 people around the world die from colorectal cancer each year. Colorectal cancer is the second leading cause of cancer-related death in developed countries. Anti-cancer therapies generally involve killing off tumor cells. A new study says, now the cancer cells can be turned back into normal tissue simply by reactivating a single gene. The study is published in the Cell.
Researchers have now found that restoring normal levels of a human colorectal cancer gene in mice stopped tumor growth and re-established normal intestinal function within only four days. Remarkably, the tumors were eliminated within two weeks, and signs of cancer were prevented months later. The study findings suggest future avenues for developing effective cancer treatments. Up to 90% of colorectal tumors contain inactivating mutations in a tumor suppressor gene called adenomatous polyposis coli (Apc).
The research team used a genetic technique to precisely and reversibly disrupt Apc activity in a novel mouse model of colorectal cancer. While the vast majority of existing animal models of colorectal cancer develop tumors primarily in the small intestine, the new animal model also developed tumors in the colon, similar to clinical patients. This approach was effective in treating mice with malignant colorectal cancer tumors containing Kras and p53 mutations, which are found in about 50% of colorectal tumors in humans.
Senior study author Scott Lowe from Memorial Sloan Kettering Cancer Centre, New York, said, "Treatment regimes for advanced colorectal cancer involve combination chemotherapies that are toxic and largely ineffective, yet have remained the backbone of therapy over the last decade."