‘Clogged pipeline’ may explain Down syndrome leukemia

by Josh Barney-Virginia, University of Virginia from Futurity:
New insight into a mysterious form of leukemia that can appear and then disappear in children with Down syndrome could have implications for other forms of leukemia and even other diseases.
Researchers have linked a mutation causing Down syndrome-associated leukemias to abnormalities in cells that produce platelets, called megakaryocytes.
Essentially, this mutation is interfering with an enzyme, Calpain 2, that acts as an initial trigger for a chain of reactions that determines size and shape of megakaryocytes. This interference causes the normal process of cellular enlargement and platelet production to get hung up.
“It’s like there’s a long pipeline and there’s a clog,” says Adam N. Goldfarb of the department of pathology at the University of Virginia. “We think it’s this pipeline that’s getting clogged in this disease and other diseases.”
As reported in the journal Developmental Cell, leukemia cells with the mutation display a critical deficiency of Calpain 2, and the enzyme’s absence leaves them stuck in an early stage of development, contributing to the development of Down syndrome-associated leukemias, Goldfarb says. And that could be the case in other forms of leukemia as well.
“These leukemias in Down syndrome aren’t that common, but this finding has implications for other leukemias in that it lets us understand basic growth and development patterns,” Goldfarb says.