New Combination Therapy Shows Promise for Aggressive Triple-Negative Breast Cancer

Triple-negative breast cancer (TNBC) is a particularly aggressive form of breast cancer, characterized by its lack of estrogen, progesterone, and HER2 receptors. This absence means it doesn't respond to many common targeted therapies, leading to a generally poor prognosis and high recurrence rates. Growth Hormone-Releasing Hormone (GHRH) and its receptors are known to be involved in the proliferation and survival of various cancer cells, including breast cancer. This study aimed to evaluate the effectiveness of combining GHRH antagonists with the chemotherapy drug docetaxel as a novel therapeutic strategy for TNBC.

In vitro, both MIA-602 and MIA-690 effectively inhibited the proliferation of TNBC cells and induced apoptosis (programmed cell death). Crucially, the combination of these GHRH antagonists with docetaxel demonstrated a synergistic effect, meaning their combined impact was greater than the sum of their individual effects. In the in vivo xenograft models, the combination therapy yielded significant improvements. > The combination of MIA-602 with docetaxel led to a significant reduction in both tumor volume and tumor weight compared to single-agent treatments or controls. Similarly, the combination of MIA-690 with docetaxel also resulted in significant reductions in tumor volume and weight, confirming the enhanced efficacy of the dual approach. Furthermore, the combination therapy was found to reduce the expression of key cancer-promoting markers such as GHRH-R, IGF-IR, EGFR, HER2, Ki-67 (a proliferation marker), and VEGF (a protein that promotes new blood vessel growth, crucial for tumor growth).