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Washington, March 28 (ANI): Researchers have found the genetic conspirators in the development of acute myeloid leukaemia.

Describing how the most common gene mutation found in acute myeloid leukaemia starts the process of cancer development, they suggested that three critical steps are required to transform normal blood cells into leukaemic ones, each subverting a different cellular process.

By charting the route towards cancer, the study identified the processes that might serve as targets for new treatments to halt the cancer’s development in its tracks and even reverse it.

The new research has shown that mutation in NPM1 is a key event in the development of a large proportion of cases of acute myeloid leukaemia and that it exerts its effect by helping cells to self-renew, a process that can be thought of as the first step towards leukaemia. The team also identify two subsequent events that are required to cooperate with NPM1 to drive cells to become cancerous.

“We have used targeted gene disruption to look at the way acute myeloid leukaemia develops in mice and have found critical steps that take place when the cancer develops. Identifying the biological steps in turn means we can look for new drugs to reverse the process,” said George Vassiliou, Consultant Haematologist, cancer researcher and first author on the study from the Wellcome Trust Sanger Institute.

The team started by developing a strain of mice that contained a ‘control switch’, that allowed the researchers to turn on mutations in the acute myeloid leukaemia gene Npm1.

When they switched on the Npm1mutations in the mice, the team saw that the mutation gave normal blood cells the ability to renew themselves more efficiently and boosted the production of a group of blood cells known as myeloid cells.

However, the team found that, despite mutations in this most frequently mutated leukaemia gene, only three out of every ten mice developed leukaemia and the disease developed only after a long time. The results suggest that the Npm1 mutation can start the leukaemic process but cannot, on its own, drive cells towards cancer.

To try to find the events that conspire to cause acute myeloid leukaemia, the team studied the same mice using a technique called ‘insertional mutagenesis’, in which tagged DNA is inserted into the mouse genome.

Using this specialised technique, researchers could accelerate the development of cancers by causing mutations in genes at random, while at the same time ‘tagging’ the altered genes, making them easy to identify.

When the process hits a gene that drives cancer, it leads to tumours in the mice - the team can then use the tag to see which genes were mutated.

Looking at the new gene mutations, the team identified three distinct processes that the mutated genes seemed to govern. While the team were able to confirm the role of Npm1 mutations in cellular self-renewal, they found other genes, which were routinely involved in one of two other processes.

The first group of genes controlled the way that cells proliferate; the second group played a role in orchestrating the genetic activity in the cells.

“In our mice two or, in most cases, all three of these cellular processes were subverted,” said Allan Bradley, from the Sanger Institute and senior author on the paper.

“In concert, these genetic mutations, which were concentrated on a tiny number of genes, transformed normal to leukaemic cells. These findings give a much clearer view of how this difficult cancer develops and propagates,” added Bradley. (ANI)