Quercetin inhibits invasion and angiogenesis of esophageal cancer cells.

BACKGROUND

Esophageal carcinoma has poor prognosis and novel therapies for esophageal carcinoma are urgently needed. Quercetin is a natural flavonoid compound that can be found in many foods. In this study, we investigated the effects of quercetin on invasion and angiogenesis of esophageal cancer cells.

METHODS

Human esophageal cancer cell line Eca109 was treated with 5 μg/mL or 10 μg/mL of quercetin. Colony formation assay was performed. Cell migration and invasion were evaluated by wound healing and transwell assays, respectively. Human umbilical vein/vascular endothelium cells (CLR-1730) were treated with Eca109 conditioned medium, and the effects of quercetin on CLR-1730 were evaluated by wound healing and tube formation assays. Protein levels of VEGF-A, MMP9, and MMP2 were determined by Western blotting.

RESULTS

The ability of colony forming in Eca109 was reduced with the administration of 10 μg/mL quercetin, but there was no difference between the 5 μg/mL quercetin group and control. The migration distance and the number of invasive cells were significantly reduced in the 10 μg/mL quercetin group. At the lower level of quercetin at 5 μg/mL, only the invasion of cells was significantly inhibited. In endothelial cells treated with Eca109 conditioned medium, cell migration and tube forming ability were suppressed. The decreased protein levels of VEGF-A, MMP9, and MMP2 were observed at the 10 μg/mL quercetin group.

CONCLUSION

Quercetin suppressed the invasion and angiogenesis of esophageal cancer cells, and the effects were associated with the decreased expression of VEGF-A, MMP2, and MMP9.