Engagement of CD99 activates distinct programs in Ewing sarcoma and macrophages
Ewing Sarcoma is the second most common bone cancer in kids and is known to be not very immunologically active. Research published last month in a paper titled “Engagement of CD99 activates distinct programs in Ewing sarcoma and macrophages” indicates that in mouse models that antibodies against a protein called CD99 inhibit tumor growth by two mechanisms in Ewing Sarcoma (EWS). First, blocking CD99 on tumor cells alters the expression of a second protein that influences whether the immune system attacks the tumor cells or not. Therefore, blocking CD99 leads to increased destruction of the tumor cells by immune cells called macrophages. Second, blocking CD99 on the macrophages increases their inflammatory response and increase their anti- tumor response. This study provides early indications of a new macrophage-based therapy for Ewing sarcoma.