P2RY2 and neoplasm: Moreover, RT-R-MDA-MB-231 cells release more ATP and adenosine extracellularly than MDA-MB-231 cells [23], and ATP and adenosine promote the tumor progression of RT-R-TNBC cells through the activation of P2Y2R and adenosine receptors (A2AR, A2BR, etc., respectively) [23,24,25].