Jenny C. Chang, MD

To identify and test potential drug targets for the treatment of triple-negative breast cancer.

Impact

Triple-negative breast cancer (TNBC) is a particularly aggressive form of breast cancer and while new immunotherapy drugs have shown some effectiveness in these patients, the response rate remains low. Dr. Chang is investigating new therapeutic strategies that may expand the arsenal of tools for treating this aggressive subtype of breast cancer. She has designed two experimental approaches to move towards this end. The first approach investigates a novel and promising regimen against metaplastic breast cancer (MpBC), a rare but highly chemotherapy-resistant breast cancer that is often triple-negative and associated with a higher rate of recurrence and poorer overall survival. The second approach is to target nitric oxide synthase (NOS) in combination with chemotherapy for treating TNBC. Her team has established state-of-the-art laboratory models to test both approaches. Their work may reveal new targeted therapeutic strategies for TNBC patients, who have poor outcomes due to high rates of recurrence, metastatic spread, and lack of approved targeted therapies.

Progress Thus Far

Dr. Chang and her colleagues discovered that the drug, L-NMMA a nitric oxide synthase inhibitor, targets a molecule known to promote tumor growth and metastasis. Using their previously developed laboratory models, they found that L-NMMA plus chemotherapy was better at reducing tumor growth and lung metastasis than chemotherapy alone. Results from a phase 1/2 trial also demonstrated benefit of L-NMMA in combination with taxane chemotherapy in patients with advanced or metastatic TNBC. The benefit was greatest in patients with locally advanced breast cancer, with a complete response – no evidence of tumor – in about one-third of patients. Studies are underway to determine the mechanism of action of this combined treatment.

What’s next

In the coming year, Dr. Chang will test the efficacy of combination therapy with L-NMMA and chemotherapy in patients with TNBC who have obesity. Obese patients with TNBC often have a higher chance of developing resistance, increased risk of relapse, and poorer survival. In laboratory models of obesity-induced breast cancer, they observed that the combination reduced tumor growth. They will continue to test this novel combination in preclinical models to unravel the mechanism of action. Based on the positive phase I/II clinical results, Dr. Chang believes that L-NMMA and chemotherapy warrants further clinical testing in larger phase 3 trials. If successful, this will move this strategy for treating TNBC and other aggressive breast cancers closer to FDA approval and give hope to these patients with limited treatment options.