FOXP3 and neoplasm: Further, CD73 is implicated in advancing tumor progression by facilitating tumor angiogenesis and interacting with cancer-associated fibroblasts through adenosine receptors such as A1R, A2AR, A2BR, and A3R vis-à-vis multiple types of immune cells such as Tregs (Foxp3+) T cells, effector T cells, natural killer (NK) cells, myeloid-derived suppressor cells (MDSCs), and macrophages, as well as B cells (9, 15).