The Effect of OPN Isoforms Inhibitor on VEGF-A, VEGF-C, KDR, CXCR4, STAT3, IL-6 and β-Catenin Gene Expression in KG-1 and U937 Cells. The suppressive effect of OPN inhibitor alone or in combination with Ara-c and CUR treatment on KG-1(A) and U937 (B) and their combination on VEGF-A/VEGF-C/KDR/CXCR4/STAT3/IL-6/β-Catenin gene expression was assessed after 24h by qRT-PCR analysis in both KG-1 and U937 cell lines. Values were normalized using the expression of the housekeeping HPRT. The mRNA levels of OPN isoforms/VEGF-C/STAT3/CXCR4/IL-6/B-catenin/KDR were decreased significantly in the Ara-c plus or without simvastatin-treated U937cells (P≤0. 05) After 48 h. while, The mRNA levels of OPN isoforms /STAT3 and β-catenin gene expression level were decreased in KG-1 cell lines after treatment with Ara-c, on the other hand, KG-1 cells in treatment with CUR shown a decrease in STAT3 and in U937 cells in treatment with CUR shown a decrease in OPN-a/VEGF-C/B-catenin and KDR. Also cells in treatment with simvastatin shown a decrease in VEGF-A, β-catenin, and AKT and three isoforms of OPN gene expression level in KG-1 and U937 cells. Values were normalized using the expression of the housekeeping HPRT. Values are given as mean ± S.E. of three independent experiments. Statistical significance was defined at *p<0.05, **p<0.01 and ***p<0.001 compared to corresponding control.