KR acts intracellularly and requires adenosine kinase activity to inhibit leukemia cell growth. (A) NBTG and (B) ABT-702 prevented the ability of KR to inhibit TEX cell growth. (C) Inhibitors of nucleobase uptake (NBTI-red squares; NBTG-blue triangles; DiPy-green inverted triangles), adenosine kinase (ABT-702-orange diamonds; 5-ITu-pink open circles; A-134974-brown open squares), adenylate kinase (Ap5A-open yellow triangles), adenylate cyclase (SQ22536-open gray diamonds), and an adenylate cyclase activator (NKH477-open blue inverted triangles) were tested at 500nM in the presence of KR. (D) TEX cells were cultured in the presence of Compound C (black circles), metformin (red squares), AICAR (blue triangles), rapamycin (green inverted triangles), compound 401 (orange diamonds), or PI-103 (pink open squares). Growth inhibition was measured using Alamar Blue. (E) Synergism between kinetin riboside and 10μM of Compound C (black circles), metformin (red squares), AICAR (blue triangles), rapamycin (green inverted triangles), compound 401 (orange diamonds), PI-103 (pink open squares), or DMSO vehicle (brown open squares) was tested using Alamar Blue. (F) Rapamycin was tested on 11 primary AML samples using Alamar Blue.