Making sense of antisense in cancer.

Making sense of antisense in cancer

Antisense molecules are tiny pieces of DNA or RNA designed to bind to a cell's own DNA or RNA and interfere with its activity. By showing they can inject such molecules easily and safely into people, researchers have now inched closer to creating antisense "drugs" that slow the course of cancer. Eighteen people with cancer received doses of the antisense molecule OL(1)p53, which kills leukemia cells but not other cells. This molecule should interfere with the production of protein from the p53 gene, says Michael R. Bishop of the University of Nebraska Medical Center in Omaha.

However, even though they gave higher doses of the antisense material to some patients, the researchers have not yet achieved a high enough concentration of this drug in the blood. They plan to extend these studies, says Bishop.

Meanwhile, they are adding OL(1)p53 to bone marrow that has been removed from leukemia patients. The marrow will be returned to these patients after treatment has killed the tumor cells in their bodies. The researchers hope that the antisense molecules will kill any leukemia cells that stow away in the transplant material, says Bishop. Also, they plan to use a different antisense drug to get rid of cancer cells in bone marrow taken from people with chronic myelogenous leukemia.