$50K grant will further research for area doctor’s cancer work
WILLMAR — A Willmar physician is undertaking research on a new form of radiation-tagged therapy for treating prostate cancer.
It’s a unique attempt to harness a specific form of radiation that can be used to target prostate cancer cells — and if it’s successful, it might someday be used on other cancers as well, Speer said. “It could potentially lead to a very successful drug that could treat many people diagnosed with cancer or those currently with limited therapeutic options,” he said.
The project is still in an early phase. Starting next month, Dr. Speer and co-investigator Dr. Bruce Thomadsen of the University of Wisconsin will formally begin working with three different laboratories to produce the radionuclide, attach it to a molecule and then test to see how well the radiation is delivered to its target.
What makes it novel: It uses a form of radiation, known as an Auger emitter, that has not previously been successfully used for targeted radionuclide therapy.
If it works, “it will be the first targeted radionuclide that uses an Auger emitter,” Speer said.
It targets NR3, a nuclear receptor in prostate cancer cells, and carries potential for treating other NR3-positive tumors, including breast cancer and some types of brain tumors.
The research is expected to take about one year but Speer said the preliminary results will probably be known by the end of this year or early in 2015.
“Once we accomplish that, we’ll proceed to animal studies,” he said. “If we can show efficacy with animals, then we start the human trials.”
Radiolabeled therapy for treating cancer isn’t new. But it’s vastly underutilized in the United States and there’s room for this form of cancer treatment to expand, said Speer.
A long-standing challenge in cancer treatment has been the toxicity of most conventional therapies. Chemotherapy and external radiation attack and destroy fast-growing cancer cells but they’re unable to differentiate between tumor and normal tissue, hence the side effects and long-term health impact of many of the most commonly used forms of cancer treatment.
More recently, cancer treatment has been evolving toward targeted therapies that deliver treatment more directly to cancer cells while minimizing collateral damage to surrounding healthy tissue. Side effects are fewer and there’s also less risk of long-term and late health issues for patients once they’re two years, 10 years or longer into survivorship.
Radiation-tagged therapy works by labeling a molecule with a radionuclide and injecting it into the patient, where it can seek out and destroy tumor cells with radiation while sparing normal tissue from the worst damage.
Besides being more effective at targeting cancer cells, the therapy can be given in smaller amounts while still accomplishing its goal. It also promises to be more effective at treating cancer that has spread to other sites, such as bone, for which conventional chemotherapy is of limited use.
“In general, radionuclides are hundreds of times more effective than chemotherapy on a molecule basis. This is what makes targeted radionuclide therapy so attractive,” said Speer.
Speer, who has been in practice as a radiation oncologist since finishing his residency in 1992 and joined the Willmar Regional Cancer Center earlier this year, developed an interest in radiopharmaceuticals about 15 years ago. “Ever since then, I’ve kept my eyes open for different treatments and what was going on,” he said.
He has completed graduate-level coursework in targeted radionuclide therapy, published a book on the use of radionuclide therapy in cancer treatment and co-authored several medical textbook chapters on the subject. This past year the American Society for Radiation Oncology named him its representative to the National Institutes of Health targeted radionuclide therapy group, a body that meets to discuss and share ideas for advancing radiopharmaceutical research.
Research is seen as critical in developing ever more effective treatments for cancer. What takes place in the lab is the first step in bringing new therapies into patient care, said Speer.
“We’re trying to design trials that are more streamlined and answer questions better so we can speed along the process,” he said. “There are many exciting new drugs that are being developed. We live in an era where medical technology is growing at an exponential rate.”