research: protein kinases and cancer

3 October 2005

New research has found that the protein kinase JAK2 is often mutated in bone marrow cancers, but a large screen of kinases in breast cancer suggests a more complex picture.

Protein kinases, key controllers of cell growth and death, are known to be important in several types of cancer. Research by Professor Tony Green and colleagues in Cambridge, and the Cancer Genome

Project, has now found that more than half of people with myeloproliferative diseases – diseases of the bone marrow – had a mutation in the tyrosine kinase JAK2.

These diseases can lead to excess production of red blood cells, platelets or connective tissue (which can reduce the amount of space in the marrow for blood cell production). The JAK2 mutation may make marrow cells too sensitive to growth factors – a notable feature of these disorders.

The role of kinases in breast cancer does not appear to be so straightforward, however. Cancer Genome Project researchers and colleagues screened all 518 known kinase genes in 25 breast cancers, but many tumours had no mutations in these genes at all.

Although a few other tumours had numerous kinase mutations with distinctive patterns, the research suggests that there is no commonly mutated kinase gene in invasive ductal breast cancer.

Baxter EJ et al. Acquired mutation of the tyrosine kinase JAK2 in human myeloproliferative disorders. Lancet 2005;365(9464):1054–61.

Stephens P et al. A screen of the complete protein kinase gene family identifies diverse patterns of somatic mutations in human breast cancer. Nat Genet 2005;37:590–2.