Ovarian cancer researcher Tony Cheung, Ph.D., first encountered cancer when he was 19 and found out his grandmother had lung cancer.
“I was young,” Cheung said in his laboratory at the Medical University of South Carolina. “I thought, we’ll win, she’ll get over that.”
He learned that sometimes, the cancer wins.
Cheung devoted his professional life to fighting cancer. Recently, he and a team of colleagues made an exciting discovery. They identified a gene, GAB2, that they believe is linked to ovarian cancer, the deadliest kind of gynecological cancer. Ovarian cancer kills about 15,000 women each year in the U.S. They published their research in the January 21 issue of the Proceedings of the National Academy of Sciences. The study tested the tumor-promoting effect of 455 genes shown by the Cancer Genome Atlas to be amplified in ovarian tumors.
|Tony Cheung, Ph.D.|| |
The work of Cheung’s team has the potential to help doctors formulate a more effective therapy for patients.
They’re looking at the genomic content of ovarian cancer to analyze how it develops. Cheung, an assistant professor of pathology and laboratory medicine in MUSC’s Department of Medicine, said they found that there is not much mutation. Instead, they observed a lot of “copy number” changes, which are alterations of genetic material. Cheung said the changes may involve up to 2,000 genes.
“We have to be aggressive on this,” Cheung said.
He said one specific gene, GAB2, when amplified, appears to help drive the development of ovarian cancer. Amplified means excessive copies of the gene are found in cancer cells.
Cheung’s research involved combining the amplified gene with ovarian and fallopian tube cells in a laboratory. His team found that it turned them into cancer cells.
Their research adds to the growing field of knowledge about the genes responsible for ovarian cancer.
Previous research shows that other genes help ovarian cancer grow as well, including the mutated BRCA1 and BRCA2 genes. That research is already helping some women make decisions that may prevent the cancer from developing or spreading.
Cheung’s research may lead to more options for women.
“We’re studying how we can use what we found to form a therapeutic strategy,” Cheung said. ‘We’re investigating the mechanisms by which GAB2 amplification promotes development of ovarian cancer. The information will provide the basis for developing novel therapeutic strategy.”
Ovarian cancer is sometimes called a silent killer, because often, by the time a woman is diagnosed, it’s too advanced for treatment to have a big impact. Its symptoms, including abdominal bloating, fatigue and frequent urination, mimic other problems that are not life threatening.
Surgery is the main treatment for ovarian cancer, with doctors trying to remove as much of the cancer as they can. Since ovarian cancer cells can “hide,” surgery is followed by chemotherapy.
“Chemo is not that specific,” Cheung said. “It’s basically poison that is not curing cancer cells sufficiently enough. A lot of cells come back. Once they become resistant, it’s lethal to the patient. We all want long-term control.”
That quest for long-term control lies at the heart of Cheung’s work.
“You want to get the answer and tell people more about the story that you find,” Cheung said. “And I always feel obligated actually to get the job done.”
Cheung is pleased with his team’s findings on the GAB2 gene, but is careful to put them into context.
“It would be overstated if I say we understand everything. Instead, we just focused on one specific gene in a study of 500 genes,” Cheung said.