June 13, 2011

Breast Cancer Drug for Colon Cancer?

(Ivanhoe Newswire) -- A treatment that combines a chemotherapy agent that is approved to treat breast cancer and a cancer-fighting antibody may be a promising therapy for colon cancer, according to new research.

About 50,000 people die from colorectal cancer each year, and more than 150,000 cases are diagnosed annually. There are limited chemotherapy treatments available for colorectal cancer.

Investigators tested the breast cancer agent lapatinib in combination with monoclonal antibody in mice. Separately, the two treatments did not increase tumor cell suppression. However, when the drugs were given together, cell death escalated.

Researchers say lapatinib increases the amount of "death receptor" protein available for TRAIL -- tumor necrosis factor [TNF]-related apoptosis-inducing ligand -- to kill off cancerous cells. TRAIL is a naturally-occurring molecule in the body that tells a cell it is time to die.

"We have discovered a mechanistic basis for combining these drugs that says one drug upregulates the receptor for the other drug, and maybe now when we combine these two drugs, we'll get an even better synergy between them," Wafik S. El-Deiry, M.D. Ph.D., American Cancer Society Research Professor and Rose Dunlap Professor and chief of hematology/oncology, was quoted as saying.

"I think that's probably the most exciting result, to be able to provide a molecular rationale for a new treatment combination for difficult-to-treat advanced colorectal cancers."

This new combination treatment is ready for clinical trials, according to the researchers. The Food and Drug Administration approved lapatinib in 2007 for use as a breast cancer chemotherapy.

SOURCE: Science Translational Medicine, June, 2011