SP1 and neuroblastoma: In clinical NB and neuroblastic tumor specimens derived from the R2: microarray analysis and visualization platform (http://r2.amc.nl), the expression of MMP-14 was positively correlated with that of MYCN (correlation coefficient R = 0.261, P = 0.014; R = 0.317, P = 0.014), VEGF (R = 0.434, P < 0.0001; R = 0.485, P < 0.0001), or Sp1 (R = 0.405, P < 0.0001; R = 0.434, P = 0.0003, Supplemenatry Figure S1C).