“Brainwashed” Immune Cells Help Breast Tumors Thrive
Inflammatory cells are reprogrammed to support cancer cell growth.
Immunologists have discovered a mechanism through which immune cells get recruited into breast cancer tumors, and instead of destroying malignant cells, immune cells are reprogrammed to help cancer grow.
“Previous studies have shown that infiltration of immune cells into tumors is of great importance for how the tumor develops and that there is a fine balance between infiltration of immune cells that attack the tumor cells and immune cells that can instead protect the tumor cells and help the tumor grow and spread,” explained Margareta Wilhelm, the corresponding author of the article published in PNAS.
Wilhelm and colleagues sought to unravel the mechanisms through which phagocytic immune cells called macrophages end up protecting tumor cells rather than attacking them.
The team identified that low levels of TAp73, a tumor-suppressing protein, are associated with more aggressive forms of breast cancer. TAp73 normally suppresses inflammation by inhibiting NFkB. The dip in TAp73 levels in tumors results in a surge of inflammatory signals.
“Downregulation or lack of TAp73 leads to a condition in which NFkB is hyperactivated and upregulates secretion of the chemokine CCL2 which attracts…
