Researchers at the University of Liverpool have concluded that blocking insulin-like growth factors in combination with administration of paclitaxel, a commonly used chemotherapeutic, showed a significant reduction in tumor cell proliferation and lung metastasis in pre-clinical breast cancer models compared to paclitaxel alone.

In a study published in Nature’s journal, Oncogene on January 25, the team led by Ainhoa Mielgo Iza, PhD, Principal Investigator and Sir Henry Dale Research Fellow at the University of Liverpool, published its findings, showing that 75% of breast cancer patients show activation of insulin/IGF-1 receptor signaling, which correlates with increased macrophage (large white blood cell) infiltration and advanced tumor stage. In patients with invasive breast cancer, activation of Insulin/IGF-1 receptors increased to 87%. The group’s study should provide the rationale for further developing the combination of paclitaxel with IGF blockers for the treatment of invasive breast cancer, and Insulin/IGF1R activation and IGF+ stroma cells as potential biomarker candidates for further evaluation.

University of Liverpool

Among the study’s key conclusions are that:

  • Tumor-associated macrophages (TAMs) and fibroblasts (the principal active cells of connective tissue) are the main sources of insulin-like growth factors IGF-1 and IGF-2 in invasive breast cancer.
  • Metastasis-associated macrophages and fibroblasts remain the main sources of IGF-1 and IGF-2 in pulmonary metastatic lesions.
  • Combination treatment of invasive breast cancer with paclitaxel and IGF blocking antibody reduces tumor cell proliferation and metastasis in mice.

I am thrilled by our findings, as the combination therapy is more effective than the current treatment in preclinical models of breast cancer.

– Lucy Ireland, PhD student and lead author of study, as quoted by Medical News Today