Optimization of polysaccharides extracted from Verbena officinalis L and their inhibitory effects on invasion and metastasis of colorectal cancer cells

Purpose: To investigate polysaccharides (PEV) extracted from the aerial part of Verbena officinalis L. and their inhibitory effects on the invasion and metastasis of colorectal cancer (CRC) cells.Methods: PEV was extracted by water and the optimization of extraction conditions was performed using a Box-Benhnken design (BBD). The cell viability was evaluated by 4,5-dimethylthiazol-2-yl)2,5-diphenyltetrazolium bromide (MTT) assay. The effects of PEV on cell adhesion and invasion were evaluated by Transwell invasion, wound healing migration and adhesion assays in vitro. The effects of PEV on the expressions of matrix metalloproteinase-9 (MMP-9), mesenchymal-epithelial transition factor (C-met), E-cadherin (E-CAD), cyclooxygenase-2 (COX-2) and E-prostanoid 2 receptor (EP2) were investigated by western blot.Results: The BBD model was established successfully for the optimization of PEV extraction (p