An international research team led by the Translational Genomics Research Institute (TGen) recently found the cause of a rare type of ovarian cancer that most often strikes girls and young women.
By applying its groundbreaking work in genomics, TGen led a study that included the British Columbia Cancer Agency, University of British Columbia, the University Health Network-Toronto, the Autonomous University of Barcelona, Mayo Clinic, Scottsdale Healthcare, St. Joseph’s Hospital and Medical Center, Evergreen Hematology and Oncology, Children’s Hospital of Alabama, Johns Hopkins University.
“This is exactly the type of scientific discovery that TGen was designed to accomplish,” said Dr. Jeffrey Trent, president and research director of TGen, and the study’s senior author. “It also is a prime example of the type of collaborative work that draws scientific expertise, and investment, to Arizona.”
The findings — published in the prestigious scientific journal Nature Genetics — revealed a “genetic superhighway” mutation in a gene found in the overwhelming majority of patients with small cell carcinoma of the ovary, hypercalcemic type, also known as SCCOHT.
This type of cancer usually is not diagnosed until it is in its advanced stages. It does not respond to standard chemotherapy, and 65 percent of patients die within 2 years. It has affected girls as young as 14 months, and women as old as 58 years — with a mean age of only 24 years old. In this study, the youngest patient was 9 years old.
“This is a thoroughly remarkable study. Many genetic anomalies often seen in cancer can be like a twisted mountain road; difficult to negotiate. But these findings indicate a genetic superhighway that leads right to this highly aggressive disease,” said Dr. Aleksandar Sekulic, an assistant professor in TGen’s Integrated Cancer Genomics Division.
“The correlation between mutations in SMARCA4 and the development of SCCOHT is unmistakable, and it is critical to explore the potential treatment implications of these findings,” said Dr. Sekulic, who also is a physician-scientist in the Department of Dermatology at Mayo Clinic in Arizona.
TGen, a non-profit research facility at the heart of the downtown Phoenix Biomedical Campus, conducts groundbreaking investigations — using state-of-the-art technology — to identify the possible genetic causes of disease. TGen does this by sequencing genomes. TGen spells out, in order, the billions of chemical letters in patients’ DNA, and compares the genomes of normal cells and diseased cells.
By noting changes in genes, TGen scientists make recommendations to oncologists and other doctors, enabling them to make the best possible choices for the care and treatment of their patients. TGen is recognized worldwide as a pioneer in this field.
Because the research was coordinated in Arizona, this study also shows the potential of TGen-led investigations to help Arizona patients first. Nearly 70 percent of patients in TGen clinical trials at Scottsdale Healthcare’s Virginia G. Piper Cancer Center are from the Grand Canyon State.
Study inspired by 22-year-old patient
Much of the work in this study was inspired by the memory of Taryn Ritchey, a 22-year-old TGen patient who in 2007 lost her battle with ovarian cancer, the fifth leading cause of cancer death among American women.
“Taryn would be incredibly excited about this amazing new study, and she would be glad and thankful that other young women like her might now be helped because of TGen’s ongoing research,” said Taryn’s mother, Judy Jost of Cave Creek. “My daughter never gave up, and neither has TGen.”
The SMARCA4 gene — previously associated with lung, brain and pancreatic cancer — was the only recurrently mutated gene in the study’s samples. The implications of this discovery, therefore, may be widespread.
“The findings in this study represent a landmark in the field. The work identifies SMARCA4 mutations as the culprit, and most future research on this disease will be based on this remarkable discovery,” said Dr. Bert Vogelstein, director of the Ludwig Center at Johns Hopkins University, investigator at the Howard Hughes Medical Institute, and pioneer in the field of cancer genomics. He did not participate in the study but is familiar with its findings.
“The past decade of research has taught us that cancer is a vastly complex disease. Profound patient-to-patient variability has made treatment and diagnosis for many tumor types at times very difficult. In this case, however, we have found a single genetic event driving SCCOHT in nearly every patient,” said Dr. William Hendricks, a TGen staff scientist and another author of the study.
“We set out to uncover any small sliver of hope for women afflicted with this rare cancer. What we found instead are the nearly universal underpinnings of SCCOHT,” said Pilar Ramos, a TGen Research Associate, and the study’s lead author. “By definitively identifying the relationship between SMARCA4 and SCCOHT, we have high confidence that we have set the stage for clinical trials that could provide patients with immediate benefit.”
— Steve Yozwiak is the TGen senior science writer