The effect of A3 AR agonists on the proliferation of diverse tumor cells, such that by as piclidenoson (IB-MECA; 20) and namodenoson (Cl-IB-MECA; 21), is characterized by their remarkable affinity and selectivity for the A3 AR, even at minimal concentrations [189,190,191]. Here, ADORA3 is linked to neoplasm.