Figure 4.

Matrix metalloproteinase (MMP) activity and vascular endothelial growthe factor (VEGF) production in MDA-MB-231 cells was regulated by P2Y₂R activation mediated by ATP or uridine 5′-triphosphate (UTP). (A) MDA-MB-231 were treated with the indicated doses of ATP or UTP for 6 h. MMP gelatinase activities were measured in conditioned media (CM) as described in Methods. Control- or P2Y₂R-shRNA-transfected MDA-MB-231 were treated with 10 μM of ATP or UTP. After 6 h, MMP gelatinase activities were determined in the CM and quantified (MMP-9; 92 KDa). Significance compared to the control, **P <0.01; significance compared to ATP or UTP, ^#P <0.05, ^##P <0.01. (B) Control- or P2Y₂R-shRNA-transfected MDA-MB-231 were treated with 10 μM ATP or UTP for 24 h, and the concentration of VEGF from the media was determined using a quantitative VEGF ELISA. Significance compared to the control, **P <0.01; significance compared to ATP or UTP, ^##P <0.01.