cientists at Washington University School of Medicine in St. Louis are using powerful DNA sequencing technology not only to identify mutations at the root of a patient’s tumor – considered key to personalizing cancer treatment – but to map the genetic evolution of disease and monitor response to treatment.
“We’re finding clinically relevant information in the tumor samples we’re sequencing for discovery-oriented research studies,” says Elaine Mardis, PhD, co-director of The Genome Institute at the School of Medicine. “Genome analysis can play a role at multiple time points during a patient’s treatment, to identify ‘driver’ mutations in the tumor genome and to determine whether cells carrying those mutations have been eliminated by treatment.”
This work is helping to guide the design of future cancer clinical trials in which treatment decisions are based on results of sequencing, says Mardis, who is speaking April 1 at the opening plenary session of the American Association for Cancer Research annual meeting in Chicago. She also is affiliated with the Siteman Cancer Center at the School of Medicine and Barnes-Jewish Hospital.
To date, Mardis and her colleagues have sequenced all the DNA – the genome – of tumor cells from more than 700 cancer patients. By comparing the genetic sequences in the tumor cells to healthy cells from the same patient, they can identify mutations underlying each patient’s cancer.