Jan. 4, 2001 -- For many patients, the one side effect of cancer treatment considered even more harrowing than nausea and vomiting is hair loss. The same drugs that often save lives also can cause very real physical hardship and emotional distress. But chemotherapy-induced hair loss may become a thing of the past if a promising new drug works as well in humans as it does in rats.
Besides killing rapidly dividing cancer cells, chemotherapy causes hair loss by killing off proliferating hair follicle cells, says study leader Stephen T. Davis, PhD. So his team attempted to create a class of compounds to inhibit a specific enzyme -- called CDK2 -- that "is a key switch for turning on cell division." They wanted to know if they could temporarily stop the normal cell cycle in the hair follicles, and whether putting cells into this state of suspended animation might make them less vulnerable to chemotherapy, he tells WebMD. The idea appears to have worked.
First, they showed in the laboratory that the compounds they developed could protect against several chemotherapy agents, "and then we went on to show that they could be applied topically to rats and produce a very robust response in terms of protecting from chemotherapy-induced hair loss," says Davis, who is senior research investigator in the department of cancer biology at GlaxoSmithKline in Research Triangle Park, N.C. The findings are published in the Jan. 5 issue of Science.
Davis and his colleagues applied the compounds to the scalps of baby rats two to four hours before giving the animals chemotherapy. "The hair was protected and remained on the scalp, and the remainder of the body, where we didn't apply the compounds, experienced complete hair loss. It was quite a dramatic contrast," he says.
According to Karen Fields, MD, who reviewed the paper for WebMD, the approach "makes a lot of sense. These compounds specifically inhibit cell cycling, and if you can inhibit the cell cycle at the right time so that the cells are in a resting stage, and then [give the] chemotherapy, the chemotherapy might not have an effect on those cells. It's a very good rationale," she says. Fields directs the bone marrow transplant program at H. Lee Moffitt Cancer Center in Tampa, Fla.