Late-stage ovarian cancer can be treated

University of Guelph researchers have discovered a peptide that shrinks advanced tumours and improves survival rates for ovarian cancer.

"We`re extremely excited about this. It has the potential, particularly in ovarian cancer, to have a significant impact," said Jim Petrik, a professor in U of G`s Department of Biomedical Sciences who conducted the research with PhD student Nicole Campbell.


Ovarian cancer is the most lethal gynecological cancer. Its symptoms, which include nausea, bloating and abdominal pain, are vague and can be attributed to a number of ailments.

Often the disease remains undetected until it`s well advanced, when the odds of survival are poor.

"It`s called the silent killer because it really does sneak up on you," Petrik said.

He and Campbell discovered that ABT-898, a peptide derived from the thrombospondin molecule, shrinks established late-stage tumours in mouse models of ovarian cancer.

In addition to regressing tumours, ABT-898 essentially prunes dysfunctional blood vessels in the tumour while leaving healthy vessels intact.

Petrik explained that chemotherapy treatment relies on blood vessels to transport tumour-fighting drugs. But abnormal blood vessels inside tumours make drug delivery inefficient.

"This new treatment enhances the ability to deliver chemotherapy drugs inside of the tumour where they need to go. So in combination with chemotherapy, it has fantastic potential," he said.

Besides shrinking tumours, ABT-898 improves survival rates because cancer cells do not have time to adapt to the treatment.

Petrik hopes the research will lead to human trials and, ultimately, to the development of targeted cancer therapies.

Their findings will appear in Molecular Cancer Therapeutics, published by the American Association for Cancer Research.