Cancer patients undergoing chemotherapy often experience hair loss. Although temporary, this effect is emotionally distressing, a constant visual reminder of the individual's condition. But the results of research published today in the journal Science may point the way to preventing such chemotherapy-induced alopecia (CIA). Many anti-cancer drugs that lead to CIA target specific phases of the cell cycle. As a result, they prove selectively toxic to cells undergoing division. The epithelium of the hair follicle is particularly sensitive to these effects because it divides so rapidly. Previous studies had shown that inhibiting cell cycle progression diminishes the toxicity of the drugs.
So with that mind, Stephen T. Davis of Glaxo Wellcome and his colleagues set out to determine whether restraining CDK2, the so-called protein kinase that directs progression of the cell cycle, might provide the necessary control over hair follicle cell division to halt CIA. They thus developed a group of synthetic CDK2 inhibitors and found that treatment with these compounds reduced hair loss in 33 to 50 percent of CIA rats. Applying the compounds topically to the scalp limits systemic exposure and avoids the danger of diluting the chemotherapy's anti-tumor efficacy. "On the basis of the evidence presented here," the authors assert, "clinical trials in cancer patients to assess the efficacy of this approach to prevent CIA may be warranted."