New Compound Offers Hope for Triple-Negative Breast Cancer Treatment

UM-164 blocks the c-Src kinase that plays a role in the growth and spread of breast cancer.

A newly identified target showed promise in the treatment of triple-negative breast cancer, a study published in Clinical Cancer Research found.

The compound, UM-164, is able to block the kinase c-Src, which is known to play a role in the growth and spread of triple-negative breast cancer, and also inhibit the p38 pathway.

“Triple-negative breast cancer is in dire need of new drugs,” said senior study author Sofia Merajver, MD, PhD. “The treatments that have dramatically improved breast cancer outcomes don’t apply to patients with this type of disease.”

Although the researchers have taken an interest in c-SRC, prior drugs designed to target this kinase have mostly proven ineffective. Existing c-Src inhibitors try to block kinase, while UM-164 binds to it, forcing the kinase to turn off.

“The reason our compound works is that we have a novel mechanism for binding the kinase,” said senior study author Matthew B. Soellner, PhD. “It has a response similar to removing the protein entirely from the cell, as opposed to only inhibiting the activity.”

Additionally, researchers found that UM-164 was able to inhibit p38. They tested an existing c-Src inhibitor alone first in cells, and then combined it with an existing p38 inhibitor.

The test results revealed that the combination therapy was more effective.

“They're much better together than they are individually,” Soellner said. “And with our compound, the outcomes were even stronger than with the existing drugs. We weren't trying to target p38, but it turns out to be a promising target in this disease.”

Although the drug is effective against cancer and causes few side effects, more laboratory testing needs to be done to better understand the safety profile of UM-164 before use in a clinical trial setting. Future research will include additional safety testing in specialized mouse models based on tissue from triple-negative breast cancer patients.