Cheap Drug May Alleviate Treatment-Resistance
Published: 2020-01-17 |
Source: Karolinska Institutet
A common and inexpensive drug may be used to counteract treatment resistance in patients with acute myeloid leukemia (AML), one of the most common forms of blood cancer. This is the conclusion of a study in mice and human blood cells performed at Karolinska Institutet and SciLifeLab and published in the medical journal EMBO Molecular Medicine. The researchers will now launch a clinical study to test the new combination treatment in patients.
One of the most common drugs to treat AML is cytarabine (ara-C), a cytotoxic drug that interferes with DNA replication. However, many patients do not respond to the treatment because their leukemic cells express high levels of the enzyme SAMHD1, which breaks down the active metabolite of cytarabine, ara-CTP. These patients have a significantly worse survival rate that patients with low leukemic levels of SAMHD1. Therefore, one promising strategy to improve the treatment of AML is to inhibit the effects of this enzyme on cytarabine.
In this study, the researchers tested the impact of more than 33,000 different substances on SAMHD1's ability to break down ara-CTP in leukemia cells treated with cytarabine. The experiment led to the identification of three different substances, so-called ribonucleotide reductase inhibitors (RNRi), that all reduced SAMHD1's ability to deactivate ara-CTP: hydroxyurea, gemcitabine and triapine.