Alexa488 coupled fluorescent secondary antibodies (Invitrogen). The fields were chosen randomly from various section levels to ensure the objectivity of sampling. In vivo matrigel plug assay Growth factor-reduced matrigel (0.6 ml) containing 20 U of heparin and no VEGF, 300 ng/ml mouse VEGF, mouse VEGF plus 0.94 mg/kg and 9.4 mg/kg of phloroglucinol was injected subcutaneously into 7-week-old male mice. After 13 days, plugs were removed from the sacrificed mice. The matrigel plugs were fixed with 4% paraformaldehyde and embedded with paraffin. Next, 5-mm sections were stained in an immunohistochemistry assay with anti-CD31 antibody in order to visualize the endothelial cells. The fields were chosen randomly from various section levels to ensure the objectivity of sampling. Statistical analysis Statistical comparison of 2 groups was performed using the Student’s t-test. The results were analyzed using the Statview 5.0 software package (Abacus Concepts, Inc., CA). Scheffe´’s test was performed for multiple comparisons between each group after ANOVA. All data, which were obtained from at least 3 independent experiments, are expressed as means 6 standard deviations. Supporting Information Figure S1 The direct role of phloroglucinol during EPC– mediated tumor angiogenesis. (A) Representative photomi- crographs of incorporated EPC (red fluorescence, Ac-LDL-labeled EPC) into CD31 (+) neovessel (green fluorescence). (B) Quantita- tive assessment of incorporated EPCs following orally administra- tion of phloroglucinol. The bar graph represents a marked difference in the number of incorporated EPCs in phloroglucinol – treated mice. (TIF) References 1. Kim MM, Kim SK (2010) Effect of phloroglucinol on oxidative stress and inflammation. Food Chem Toxicol 48: 2925–2933. 2. Kang KA, Lee KH, Chae S, Zhang R, Jung MS, et al. (2006) Cytoprotective effect of phloroglucinol on oxidative stress induced cell damage via catalase activation. 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