Researchers at the University of Guelph (ON, Canada) have discovered a new way to reduce the size of tumors and improve drug delivery in ovarian cancer, an advance that could potentially result in reduced chemotherapy doses and decreased therapy-related side effects. The findings were published recently in The FASEB Journal.
“We hope that this study will lead to novel treatment approaches for women diagnosed with late-stage ovarian cancer,” commented Jim Petrik (University of Guelph). “The development of new therapies to treat women with advanced ovarian cancer is essential in order to reduce the morbidity and mortality associated with this disease,” he continued.
Approximately 150,000 women die every year worldwide from ovarian cancer, making it the most lethal gynecological cancer. Due to the vague nature of the symptoms (e.g., nausea, bloating and abdominal pain), women often go undiagnosed for many years. In fact, in approximately eight out of ten cases, cervical cancer is not detected until the disease reaches an advanced stage, at which point the chances of survival are poor. “This is why it’s known as the ‘silent killer’,” commented Petrik.
Petrik also explained how the inefficient delivery of chemotherapy drugs allows for the development of resistance to treatment, often causing women to succumb to ovarian cancer. “The 5-year survival rate for ovarian cancer has changed very little over the last 20 years, and new treatment options are urgently needed.”
Using an animal model of advanced-stage ovarian cancer, Petrik’s study looked at a portion of a naturally occurring protein inhibitor molecule termed 3TSR. This molecule interacts with another protein found on endothelial cell surfaces and in doing so reduces abnormal tumor angiogenesis.
“With this novel approach, we were able to both shrink the tumor and enhance the ability of the tumor to take up chemotherapy drugs,” Petrik explained. “We also made the surprising discovery that 3TSR causes ovarian cancer cells to die through a direct inhibitory effect against the tumor itself.”
“One of the main problems with current treatment regimens is the significant side effects caused by the high doses of chemotherapy that women with ovarian cancer receive,” Petrik commented. As a result of more efficient drug delivery, patients may be able to receive lower doses of chemotherapy, which could reduce many of these side effects.
Looking forward, the team are now working toward human trials, with the ultimate goal of developing targeted cancer therapies.