Drug to fight leukemia in sight, say Australian researchers

After discovering a potential molecular “target” for leukemia, Australian researchers say a drug to fight the disease is “in their sights,” although it is still very early days. Writing in the journal Blood, they describe how the interaction of two proteins – Myb and p300 – appears to be essential to the development of acute myeloid leukemia.

Acute myeloid leukemia (AML) is the deadliest form of leukemia. It is a rare cancer that generally affects older people – it is uncommon before the age of 45.

AML affects the blood and bone marrow, causing an overproduction of immature white blood cells, called myeloblasts or leukemic blasts. These cells crowd the bone marrow and stop it from making normal blood cells.

The American Cancer Society estimate that in 2014, about 18,860 Americans will discover they have AML and about 10,460 will die of the disease.

Figures from the Leukemia Foundation show about 900 Australians are diagnosed with AML every year.

Interaction between Myb and p300 ‘critical’ to development of AML

Tom Gonda, senior investigator and professor at the University of Queensland School of Pharmacy, says their new study shows how critical the interaction between Myb and p300 is to the development of AML, and how its disruption “could lead to a potential therapeutic strategy.”

“This finding could lead to our team developing a drug to block this interaction and stop the growth of not only acute myeloid leukemia cells but probably the cells of other types of leukemia as well,” he adds.

The gene that codes for the Myb protein is the MYB oncogene, a cancer-promoting gene that is required for the continued growth of leukemia cells.

However, Prof. Gonda points out the gene is also essential for making normal blood cells, so any targeting needs to take this into account so it does not block normal cell production as well.

Fortunately, the team discovered that normal blood cells continue to form in the absence of the Myb-p300 interaction, suggesting this could be a drug target that is safe for patients.

Early days and high risk, but potential to fight leukemia and other cancers is there. The work is still at a very early stage, says Prof. Gonda, and “although a high-risk project, it has the potential to produce large benefits in the fight against leukemia and, possibly, other cancers.”

Although the development of new drugs and then testing them in clinical trials takes a very long time, he is hopeful that this avenue of research has a promising future, he adds.

Another possibility the team has in mind is to look at ways to target genes and proteins that work “downstream” of MYB, so as not to upset the normal blood cell function of MYB.

“If we can block the downstream molecules that are controlled by MYB, we may end up with the same result,” Prof. Gonda explains.