Danazol improves telomere length and peripheral blood cell counts. (A) Box plot shows changes in telomere length as measured from peripheral blood leukocytes by quantitative polymerase chain reaction at landmark visits as compared with baseline. The light dashed line represents the anticipated rate of telomere attrition with age in healthy persons (60 bp per year), and the bold dashed line represents the anticipated rate of attrition in patients with telomere diseases (120 bp per year). The line within each box indicates the median; the top and bottom edges the 75th and 25th percentiles, respectively; and the I bars the range. Patients were treated for 24 months (light blue shaded areas), but followed for at least 36 months. (B) In analogy, different blood cell lineages during (circles) and after (squares) danazol treatment. Black symbols indicate protocol qualifying low prestudy values. Gray symbols represent counts higher than the protocol required threshold. Patients with unilineage or multilineage cytopenias were enrolled. Reprinted from Townsley et al62 with permission.
