Figure S1 - Osteopontin Upregulates the Expression of Glucose Transporters in Osteosarcoma Cells

Low dose of phloretin enhances cell death of osteosarcoma in osteopontin knockdown cells. Knockdown of OPN expression (24 h) by transient transfection of OPN-shRNA (shOPN1 and shOPN2) induced approximately 10% cell death in MG63 (A) and U-2OS (B) cells. Inhibition of glucose transporter activity by phloretin (100 µM, 6 h) caused cell death in the empty vector (ev) group. The cytotoxic effect of phloretin was enhanced by OPN knockdown in both MG63 (A) and U-2OS (B) cells after short duration of 6 h treatment. Cell viability was measured by MTT assay. Data are presented as the mean ± S.E.M. (n = 4). *p≤0.05, compared with control group (con); #p≤0.05, compared with respective vehicle-treated group. (DOCX)