Decoding the Paradox: White Blood Cells As Double Agents in Breast Cancer

Recent research highlights the dual role of VEGF-C-producing macrophages in breast tumors, potentially guiding metastasis to less harmful areas, opening new avenues for targeted cancer therapies.

A new study from Karolinska Institutet published in Cell reports shows that tumor-associated macrophages, which are white blood cells that are found in breast tumors, can both help and hinder the spread of cancer cells to other organs. The researchers found that macrophages that produce a substance called VEGF-C reduce the spread of breast cancer to the lungs but increase the spread to the lymph nodes. This may have implications for the prognosis and treatment of breast cancer.

Understanding Breast Cancer and the Role of TAMs
Breast cancer is one of the most common cancers in the world, and most cases are hormone-dependent and can be treated with hormone therapy. But even several years after diagnosis, breast cancer can spread to other parts of the body, such as lungs, brain, and bone marrow. It is not entirely clear what causes this long-term risk, but a possible factor is the white blood cells called tumor-associated macrophages (TAMs). TAMs are abundant in breast tumors, playing a dual role in facilitating and impeding the spread of cancer cells. Specifically, perivascular TAMs, a subset wrapped around vessels, regulate blood vessel function and guide or block cancer cell entry into the vasculature, impacting their potential spreading to other organs.