Washington University School of Medicine is undertaking a collaborative effort with St. Jude Children’s Research Hospital in Memphis to reveal the genetic origins of childhood cancers.
Researchers at the Washington University Genome Center will decode the genomes of more than 600 childhood cancer patients from St. Jude, who have contributed both tumor and healthy tissue samples. Scientists will compare the differences in the DNA to identify genetic changes that lead to cancer.
While great progress has been made in treating childhood cancer, it is still the leading cause of death from disease among U.S. children over one year of age, and cure rates for some childhood cancers remain below 50 percent.
“We expect the knowledge we gain will point to better ways to find, treat and someday even prevent cancer,” said Dr. James Downing, scientific director at St. Jude.
“We anticipate a variety of factors, including race and ethnicity, might impact not only the risk of developing cancer, but also how patients respond to anti-cancer drugs.”
Scientists at the Washington University Genome Center pioneered reasearch in whole-genome sequencing with cancer patients’ genomes. In 2008, Richard Wilson, Ph.D., director of the center, along with co-director Elaine Mardis, Ph.D., Dr. Timothy Ley and colleagues, became the first to decode the complete genome of a cancer patient and trace the disease to its genetic roots.
They have since sequenced the genomes of additional cancer patients, including those with breast, lung and ovarian tumors and glioblastoma, a type of brain tumor. These studies have identified intriguing and unexpected genetic connections between patients with different types of cancer that likely would not have been discovered using conventional approaches.
“We actually did this for an African-American woman who I think lived in the St. Louis area and died from a particularly bad case of breast cancer,” Wilson said.
“And we found that there were changes in her DNA that may have been related to it becoming a much more dangerous cancer, metastasizing into her brain.”
Wilson said DNA evidence matched with other indicators will effectively guide treatment.
He said, “We’re going to be able to say, ‘Okay, if a patient of this particular race comes into the hospital with this particular type of cancer, odds are, based on the data, that we might want to very quickly go down this treatment pathway because it’s going to be more effective to cure their cancer.’”
Downing at St. Jude said African-American children have a lower incidence of childhood cancer compared to other races. St. Jude doctors have found that cancer survival rates for African-American children have reached parity with white children when treated with protocol-based therapy.
“This improvement is mostly based on advances made in the survival rates for African-American children treated for acute lymphoblastic leukemia, the most common childhood cancer,” Downing said.
St. Jude is home to one of the world’s largest and most complete repositories of biological information about childhood cancer. It includes more than 50,000 tumor, bone marrow, blood and other biological samples collected since the 1970s and deemed essential to efforts to understand the origins of cancer.
The St. Jude Children’s Research Hospital-Washington University Pediatric Cancer Genome Project is estimated to cost $65 million over three years. Kay Jewelers has committed to providing $20 million as lead sponsor. For more information about the project, visit pediatriccancergenomeproject.org.