Expression of SPRY2 induces spontaneous apoptosis in CLL cells. (A) Mec-1 cells were transfected with empty and spry2-cDNA GFP co-expressing vectors. (B) Annexin V staining done after 48 and 72 hours. Only “live” cells were gated for the analysis. The numbers represent the percentage of GFP-positive cells also positive for Annexin V. (C) Primary CLL cells from different poor-prognosis CLL patients were nucleofected with spry2-cDNA and empty vector (n = 5). Bar graph represents fold in percentage of apoptotic cells. (D) Mean fold change of spry2-cDNA and empty vector transfected cells from (C). P = .009.