College of Engineering News • Iowa State University

Developing polymer drugs for cancer treatment

Kaitlin Bratlie

Through research on drug delivery systems, Kaitlin Bratlie, assistant professor of materials science and engineering and chemical and biological engineering at Iowa State, is working on a way to treat cancers that don’t respond well to current treatments.

Her project has been underway for just a year and is several years away from clinical trials, but she says it’s the potential that keeps her motivated.

“These developments could actually turn around the prognosis of some cancer patients,” she explains.

Bratlie’s project is targeting tumor-associated macrophages, which are cells found in certain cancers and enhance the progression of tumors by creating blood vessels. She is looking to reprogram these macrophages to act instead like pro-inflammatory macrophages that prevent cancerous cells from becoming tumors.

Assisted by a team of four graduate and seven undergraduate students, she is currently developing a delivery vehicle for the drugs used to treat patients. Bratlie says other researchers have explored biodegradable polymers, but her research uses a polymer to encapsulate the medicine.

Through a grant from the National Science Foundation, Bratlie’s team is looking at a variety of chemical characteristic groups to determine their reactions with the polymer that would be used in delivering cancer-fighting medication. They want to uncover a functional group that will alter macrophage secretion profiles into pro-inflammatory macrophages

Once they have the correct functional group, the researchers plan to chemically modify a hydrogel that can encapsulate a drug within the polymer. The drug will be tested in animals, and they will look for apoptosis, or cell death, to ensure the treatment kills the cancerous cells.

Like most new developments in the world of science, Bratlie’s work with drug delivery mechanisms stems from a gap in knowledge. In this case, the gap pertains to cell responses to biomaterials. Her knowledge relating to drug release came from her post-doctoral work, which, in part, involved using biodegradable polymers to do a controlled release of corticosteroids to reduce the foreign body response to transplanted artificial organs.

“I identified a gap in the literature, and then happened to be using the drug delivery devices themselves to reprogram these macrophages,” says Bratlie. “And that’s why we’re going down this road.”

Bratlie says success with this project could offer cancer patients being treated unsuccessfully with current drug therapies a different outcome. “It would change people who have poor prognoses to actually being cured of cancer,” she adds.