Acute myelogenous leukemia (AML) is the most common type of leukemia (cancer of the blood) in adults. It occurs in myeloid cells and progresses more rapidly than chronic leukemias. Myeloid cells are a class of blood cells that develop into red and white blood cells and platelets. Though cure rates for AML remain low, Johns Hopkins hematologic oncologists are experts in treating refractory acute leukemias. Fewer than 20 percent of AML patients older than 60 survive beyond one year. Because of this, there is no standard treatment regimen and many patients opt to enroll in clinical trials.
New Treatment Approaches
Our experimental therapeutics program focuses on patients with poor-risk leukemia with the goal of increasing the number, quality and duration of remissions, cures and improvements in quality of life. Patients with poor-risk leukemia include those with complex disease, specific gene factors (mutations and deletions in certain genes), age greater than 60, development of leukemia as a secondary effect of myelodysplastic syndrome, or systemic disease. Our investigators are studying the effectiveness of blending new targeted therapies with existing treatments and methods for diagnosing and treating minimal residual disease.
- Farnesyltransferase inhibitors
Johns Hopkins Kimmel Cancer Center investigators are among the world’s experts in studying a new therapeutic class of compound called farnesyltransferase inhibitors, which block certain enzymes involved in cell-to-cell communication. Investigators at Johns Hopkins led the first study of one of these compounds in elderly patients to find that it may have an advantage for this population segment. Studies underway include determining the drug’s dosing and schedule and combinations with existing chemotherapy agents and other new targeted therapies.
- FLT3 inhibtors
Also pioneered at Johns Hopkins is the development of drugs that block protein products made by the FLT3 gene, which was first cloned by Johns Hopkins scientists. Mutations in the gene and their faulty protein products can be found in up to 40 percent of AML patients and are characterized by aggressive disease. Investigators continue to test FLT3 inhibitors and combine it with chemotherapy.
One focus of basic science discovery at the Johns Hopkins Kimmel Cancer Center involves the mechanisms by which genes are silenced not only by changes in their DNA code, but by chemicals that influence the shape and activation of certain regions of DNA. Such epigenetic alterations include a process called methylation, where tiny methyl groups tack on to the on/on switch of genes. With too much methylation, genes important for stemming cancer growth can be silenced. Drugs that inhibit these epigenetic changes are being combined and tested for AML and myelodysplastic syndrome as well as staging and diagnosing other cancers. Histone deacetylase inhibitors, which represent another method to silence genes, are also being studied.
- Cell Cycle Inhibitors
The experimental drug flavopiridol is being studied for poor-risk disease as an up-front therapy for AML and relapsed or refractory acute leukemias. The drug works by blocking cells from progressing to more mature stages of the cell cycle that are responsible for multiplication and growth.
Johns Hopkins scientists are developing therapies that may help the body’s immune system fight cancer. Pioneered by basic science and clinical immunology experts at Johns Hopkins, such therapies, including vaccines, which target specific aspects of leukemia cells, are being developed for acute and chronic myelogenous leukemias.