Research groups such as Nagoya University have reported that they have discovered a new causative gene by conducting a comprehensive genetic analysis in pediatric patients with juvenile myelomonocytic leukemia (JMML).
JMML is a type of intractable childhood cancer that occurs in infancy.Previous studies have found five causative genes associated with the RAS pathway (one of the intracellular signaling pathways associated with cell proliferation), but the causative genes in some cases were unknown.
This research group performed various gene analyzes on 150 JMML patients using a powerful analysis method called the next-generation sequencer.As a result, we found fusion of abnormal genes associated with ALK / ROS3 tyrosine kinase in 1 patients with no abnormalities in the RAS pathway gene.Two of them did not respond to standard treatments (chemotherapy or bone marrow transplantation) and died early after onset, considered to have a very poor prognosis.Another patient developed a tyrosine kinase inhibitor during the study period and was fortunate to be able to identify a tyrosine kinase fusion gene early after diagnosis, so she used a tyrosine kinase inhibitor that is already used to treat lung cancer and the like. The target treatment was performed.Then, about one month after the start of administration, the tumor cells disappeared almost completely, and the disease could be completely cured.
In addition, the results of total methylation analysis revealed that there is a "hypermethylated group" in JMML patients who has abnormal DNA methylation involved in gene regulation, which is much higher than other patients. I found that the prognosis was poor.
Based on these results, we will develop treatments using inhibitors for tyrosine kinase-related fusion genes and stratified treatments based on DNA methylation (methods that provide appropriate intensity treatment according to the malignancy of the disease). It is expected that the treatment results of JMML will be improved.
Paper information:[Blood] Integrated molecular profiling of juvenile myelomonocytic leukemia