Gene Activity May Affect Acute Myeloid Leukemia Outcome

For acute myeloid leukemia patients, overactive genes in their leukemic stem cells (LSC) can translate into a more difficult struggle to overcome their disease and achieve prolonged remission, new research reveals. "In many cancers, specific subpopulations of cells appear to be uniquely capable of initiating and maintaining tumors," the study authors explained in their report. The researchers identified 52 LSC genes that, when highly active, appear to prompt worse outcomes among acute myeloid leukemia (AML) patients.

Between 2005 and 2007, study author Andrew J. Gentles, of Stanford University in Palo Alto, Calif., and colleagues examined gene activity in a group of AML patients as well as healthy individuals. Separate data concerning AML tumors in four groups of patients (totaling more than 1,000) was also analyzed. In one of the patient groups, the investigators found that higher activity levels among 52 LSC genes meant a 78 percent risk of death within a three-year period. This compared with a 57 percent risk of death in the same time frame for AML patients with lower gene activity among these specific "signature" genes.

In another AML patient group, the research team observed that higher gene activity prompted an 81 percent risk for experiencing a disease set-back over three years, compared with just a 48 percent risk among patients with low gene activity. What's more, Gentles and his colleagues found that higher activity among these 52 LSC genes generally meant a poorer response to chemotherapy treatment and lower remission rates.