The world’s biggest cancer research effort – being led from Canada – has yielded its most promising find: four mutated genes in a fatal but most common form of leukemia.
Published in Nature on Sunday, Spanish researchers have identified the recurrent mutations of four genes that cause chronic lymphocytic leukemia, a cancer of the blood and bone marrow.
“This is just the start of a much bigger project,” said Thomas Hudson, president and scientific director of the Ontario Institute of Cancer Research and co-founder of the International Cancer Genome Consortium, the group that announced the research findings.
The consortium, headquartered in the MaRS building in Toronto, has researchers from 13 countries working to sequence and analyze 500 tumour genomes in each of the 50 most frequent cancers. It is considered one of the most ambitious biomedical research efforts involving the Human Genome Project.
In this particular research, Spanish Chronic Lymphocytic Leukemia Genome Consortium scientists found 1,000 mutations in more than 300 patients with chronic lymphocytic leukemia studied, of which four were particularly relevant.
“The diagnosis of disease is moving away from the organ towards the mutation and it’s the mutation that becomes the basis of selection therapy,” Dr. Hudson said in a telephone interview. “And that becomes personalized medicine.”
Cancer research has changed dramatically over the past decade to focus on the hunt for genetic mutations that could lead to targeted therapies.
“The time to develop targeted therapies is becoming shorter and shorter now that we know how it works,” said Dr. Hudson.
Some examples of targeted therapies include the discovery of the HER-2 gene, which resulted in a drug, trastuzumab, that turned a particularly deadly form of breast cancer into a highly treatable one.
Two new drugs – vemurafenib and ipilimumab – that target the genetic mutation B-RAF, which cause melanoma tumors to grow and spread, are found to increase survival in patients with advanced disease. Results on those two studies were presented at the annual American Society of Clinical Oncology meeting in Chicago on Sunday and published online by the New England Journal of Medicine.
