Researchers at the University of Oxford have uncovered a potential new therapeutic target in a particularly aggressive and hard-to-treat form of leukaemia.
A potential treatment for blast phase myeloproliferative neoplasm (BP-MPN), one of the most aggressive forms of leukaemia, has been identified by the team at the MRC Weatherall Institute of Molecular Medicine (MRC WIMM), who were supported by the National Institute for Health and Care Research Oxford Biomedical Research Centre.
In a study published in Nature Genetics, researchers investigated the role of chromothripsis — a dramatic event in which chromosomes shatter and are stitched back together in disordered ways — in BP-MPN, a characteristically treatment-resistant type of leukaemia.
The team found that a quarter of patients with BP-MPN carried an abnormal gain of genetic material from chromosome 21, known as chr21amp. The team analysed samples from 64 patients with BP-MPN. In some cases, this abnormal gain was caused by chromothripsis, highlighting the disruptive impact of this phenomenon in cancer genomes.
Crucially, the study showed that this chromosome amplification was linked to poorer outcomes in patients with BP-MPN, making it a potential biomarker for more aggressive disease. Within the amplified region, researchers identified a single gene, DYRK1A, as consistently overexpressed and more accessible in the DNA of cancer cells carrying this abnormality.
Further experiments revealed that the BP-MPN leukaemia cells are highly dependent on DYRK1A for survival and growth. Blocking DYRK1A — either by genetic knockdown or using chemical inhibitors — significantly impaired the cancer cells.
Lead author Dr Charlotte Brierley from the University of Oxford’s Radcliffe Department of Medicine said: “Together, these findings suggest that chr21amp is not only a marker of poor prognosis in BP-MPN but also points to DYRK1A as a promising druggable target, that arises specifically from chromothripsis-related changes in the cancer genome.
“This is the first time that chromothripsis has been linked to a therapeutic vulnerability. Although BP-MPN leukaemia is rare, these findings could be applicable in other forms of cancer.”
Co-author Professor Adam Mead, also from the University of Oxford’s Radcliffe Department of Medicine, added: “This is an example of how deep molecular profiling of patient samples can lead to the discovery of novel therapy targets in diseases with an unmet need. As a next step we are exploring the possibility of starting a clinical trial using already available DYRK1A inhibitors.”