(dailyRx)
Researchers believe that targeting the cancer gene FLT3 could cure one type of leukemia, and say results from their research explain the failure of several drugs currently used.
Scientists studying the genetic relationships involved in acute myeloid leukemia have used the genetic data produced in their research to refine the search for a new drug, and testing of one candidate is underway.
The group from the University of California in San Francisco announced that the gene FLT3 was being investigated as a possible target for treating acute myeloid leukemia, and so far they have not been discouraged by the failure of several drug therapies targeting that gene to get the expected results.
Results from further research showed that the targeting FLT3 is a valid therapy, but the drugs used so far in trials were not strong enough to completely shut off the gene.
Research on acute myeloid leukemia turned up FLT3 as a candidate for pharmaceutical therapy, but debate was strong over how important the gene was to survival of the cancer cells.
This report also backs up the initial conclusion that FLT3 is essential for the process where abnormal cells are transformed into a full blown leukemia.
The first clinical trial involved eight patients with leukemia and the experimental compound AC220.
Initially a success, remission was achieved in each case that the compound AC220 was used in, but all eight patients would later have a recurrence of their leukemia.
“These mutations are critically important for the survival of leukemia cells that harbor them,” said Neil Shah, MD/PhD, study author.
“Our results also identify drug-resistant mutations in FLT3 that represent high-value targets for future drug development, and will hopefully rekindle interest in developing potent FLT3 inhibitors for the treatment of acute myeloid leukemia.”
The study was published online in the journal Nature on April 15.
Financial relationships with Astellas Pharma, Ambit Biosciences, and Pacific Biosciences were disclosed by researchers.
According to the Leukemia and Lymphoma Society, there are over 245,000 people in the United States living with some form of leukemia, and over 44,000 new cases will be diagnosed each year. Among children with cancer, one out of every three will have some form of leukemia. However, over 90% of all cases of leukemia occur in adults.
Leukemia broadly defines a number of different cancers that originate in the bone marrow and blood cell lines, and typically produces an abnormal increase in the number of white blood cells in the body. Leukemias are subdivided into whether they are acute (occur rapidly) or chronic (develop over many years) and then further subdivided into what type of blood cell they start from, lymphocytic (usually from white blood cells that fight infection, like B-cells) or myelogenous (arising from cells in the bone marrow that eventually produce red blood cells). These categories make up the four most common types of leukemia:
- Acute Lymphoblastic (ALL): Affects adults over age 65 (50% survival); also the most common form of leukemia in children (85% survival)
- Chronic Lymphocytic (CLL): Affects mostly men over age 55 (75% survival)
- Acute Myelogenous (AML): Affects mostly adult men (40% survival)
- Chronic Myelogenous (CML): Affects mainly adults (90% survival)