Chronic Myelomonocytic Leukemia Patients Sought To Test New Drug Therapy at Moffitt Cancer Center

July 24, 2013

TAMPA, Fla. (July 24, 2013)Moffitt Cancer Center researchers are recruiting chronic myelomonocytic leukemia patients to test the effectiveness of the drug ruxolitinib. Chronic myelomonocytic leukemia, a genetically diverse malignancy that can transform into acute myeloid leukemia, is an aggressive disease with a three-year survival rate of 20 percent.

In a study published in the June 20 edition of the journal Blood, the researchers reported that chronic myelomonocytic leukemia is hypersensitive to the protein granulocyte-macrophage colony stimulating factor (GM-CSF), which triggers the production of white blood cells, and may be a therapeutic target.  Inhibiting the GM-CSF signal within chronic myelomonocytic leukemia cells in the laboratory resulted in cancer cell death.  

“We have shown that inhibiting GM-CSF and other molecules downstream of GM-CSF is deadly to chronic myelomonocytic leukemia cancer cells,” said study lead author Eric Padron, M.D., assistant member of the Malignant Hematology Department at Moffitt. “Our clinical trial to test ruxolitinib is currently accruing chronic myelomonocytic leukemia patients at Moffitt and will eventually be open to patients at six centers across the United States.”

GM-CSF hypersensitivity was detected in 90 percent of the chronic myelomonocytic leukemia samples the researchers tested. Study results indicate treatment with a GM-CSF-neutralizing antibody along with JAK2 inhibitors offers a therapeutic potential.

“Our results indicate that the vast majority of chronic myelomonocytic leukemia patients respond with more vigor to GM-CSF treatment,” said study co-author P.K. Epling-Burnette, Pharm.D., Ph.D., senior member of the Immunology Program at Moffitt. “This is important because cell death was evident upon GM-CSF neutralization.”

Researchers found that GM-CSF neutralization significantly decreased the number of malignant cell colonies and the molecular organization in chronic myelomonocytic leukemia. They consider GM-CSF an excellent chronic myelomonocytic leukemia-specific therapeutic target.

About Moffitt Cancer Center

Located in Tampa, Moffitt is one of only 41 National Cancer Institute-designated Comprehensive Cancer Centers, a distinction that recognizes Moffitt’s excellence in research, its contributions to clinical trials, prevention and cancer control. Since 1999, Moffitt has been listed in U.S. News & World Report as one of “America’s Best Hospitals” for cancer. With more than 4,200 employees, Moffitt has an economic impact on the state of nearly $2 billion. For more information, visit, and follow the Moffitt momentum on Facebook, twitter and YouTube.