New Attack by a “Smart Bomb” Against Triple-Negative Breast Cancer

A new preclinical study by U.S. researchers suggests that targeting triple-negative breast cancer through two complementary mechanisms can kill cancer cells, slow tumor growth, and limit disease progression.

Researchers at The Ohio State University Comprehensive Cancer Center (OSUCCC–James), including the Arthur G. James Cancer Hospital and Richard J. Solove Research Institute, have reported the approach. The findings could help guide the development of new treatments for this difficult-to-treat form of breast cancer.

Dr. Xiaoguang Liu, one of the researchers involved in the project, said the study points to a potential new strategy for combating triple-negative breast cancer by combining a targeted “smart bomb” drug with a treatment that shuts down cancer cells’ energy-producing machinery.

“These results represent an initial step,” Liu said. If the approach continues to show promise in further laboratory studies and clinical trials, it could potentially lead to more effective treatments with fewer side effects than current therapies.

The research also provides insights into how triple-negative breast cancer cells survive during treatment. The findings suggest that cancer cells may become more vulnerable when one therapy delivers a drug directly to them while another disrupts their energy supply.

Triple-negative breast cancer lacks estrogen and progesterone receptors and does not express high levels of the HER2 protein. Many breast cancer treatments work by targeting one of these characteristics. Because triple-negative breast cancer lacks these conventional therapeutic targets, fewer targeted treatment options are available. This subtype is also associated with a greater risk of recurrence and disease progression after treatment, which can contribute to poorer long-term survival outcomes.

The researchers combined two treatments that attack cancer through different mechanisms.

The first was an antibody-drug conjugate (ADC), a targeted therapy designed to deliver a drug to cancer cells expressing the CD276 protein on their surface. The second was a gene therapy approach known as cmLumiOpto, which disrupts mitochondria—the cellular structures responsible for producing energy.

In two preclinical models of triple-negative breast cancer, the combination killed cancer cells, slowed tumor growth, and reduced cancer progression more effectively than either treatment alone. The findings suggest that simultaneously targeting CD276 and cancer cells’ energy-producing machinery could be a promising strategy for further investigation in triple-negative breast cancer.

However, the researchers cautioned that findings from preclinical models do not necessarily translate to humans. Such models may not capture all the biological processes involved in human triple-negative breast cancer.

Further research is needed to determine the optimal drug doses and treatment schedules. Future studies must also assess long-term safety, potential side effects, and whether tumors can develop mechanisms to evade or resist the combined treatment.