January 13, 2020

Breast cancer is a leading cause of death among women, but it only becomes lethal if it metastasizes and spreads to other parts of the body. New research at the University of Chicago is focused on a transformative therapy for patients with metastatic tumors who currently have limited treatment options. Led by Marsha Rosner, Charles B. Huggins Professor in the Ben May Department for Cancer Research, this treatment was developed for patients with triple-negative breast cancer, an extremely aggressive cancer resistant to many drug therapies. Instead of relying on drug treatment to destroy the cancer cells, Rosner’s plan focuses on converting metastatic cells to benign tumors.

"We aren’t trying to kill the tumors," Rosner explained. "We’re trying to make them turn into benign tumors that can then be treated with other drugs or be surgically extracted. Drug-resistant cells tend to be metastatic, and those are the cells that take over and find other routes to spread throughout the body. We need to block those mutations, which is what this treatment can accomplish."

Rosner’s approach differs from many existing treatment plans for metastatic breast cancer, which typically use chemotherapy and other targeted drugs to destroy fast-growing cancer cells. Chemotherapy can also affect healthy cells and doesn’t always successfully eliminate all cancer cells, which can lead to relapse and metastasis. Working with an interdisciplinary group of colleagues ranging from clinicians to mathematicians, Rosner is focused on using small doses of existing drugs to reprogram cells within patients’ bodies to result in moving metastatic cancer cells to a benign state. This process means that drug therapies don’t have to be administered at such high doses to achieve results: metastatic tumors can be controlled in another way, and patients can ultimately reduce the amount of drugs they’re taking. 

Rosner’s current work builds upon her recent study on another new treatment for triple-negative breast cancer that uses a combination drug therapy based on a natural protein within the body that targets mitochondria. Using the body’s natural metabolism, the treatment alters resistant cells in a way that makes them respond to drugs that have been previously ineffective. Results of this study were published last year in Nature. 

Triple-negative breast cancer currently lacks many targeted drug therapy options, and Rosner suggests that even if new drugs are identified to treat this type of cancer, the focus should still be on eliminating the metastasis first.

"We may be using cancer drugs the wrong way," she said. "We’ve learned that when you kill cells and suppress any target too much, you stress the system out. Recurrence often happens because we activate the cancer cells with drugs, and the cells then migrate and look for additional pathways to move around their environment. Instead of doing that, we need to get those cells to a less heterogenous state and block the output by turning them into benign tumors we can then target without worrying about them spreading."

Although Rosner’s lab focuses on breast cancer treatment, she thinks this new treatment could successfully be applied to patients with other types of metastatic cancer. The research is currently being submitted for publication and Rosner hopes to begin introducing the process to patients soon. Learn more about Rosner’s work here.