Mammary tumor COX-2 expression in immunocompromised mice contributes to splenic MDSC expansion and alters splenic metabolism

Tumor COX-2 expression in breast cancer has been associated with increased aggressiveness. Here we have investigated the effects of tumor COX-2 levels on spleen metabolism and on the expansion of myeloid derived suppressor cells (MDSCs) that potentiate cancer progression. Studies were performed with human triple negative breast cancer cells in immune suppressed mice and mouse breast cancer cells in immune competent mice. COX-2 levels significantly altered splenic metabolism and MDSC expansion in immune suppressed mice but not in immune competent mice that may have implications for breast cancer patients that are immune compromised.