The Molecular Mechanism Of Baicalin Inhibiting The Growth, Migration And Invasion Of Colorectal Cancer Cells

Colorectal cancer(CRC)is diagnosed the third most common cancer and the fourth leading cause of cancer-related mortality worldwide.In our country,because of the changes in the living environment and life-style,the colorectal cancer incidence increased year by year in China in recent years.We have an urgent requirement to further study the causes and treatment of colorectal cancer,and cure colorectal cancer.Baicalin is a major active flavonoid derived from the root of Scutellaria baicalensis Georgi,which is a traditional Chinese herb medicine.Recent Studies have shown that baicalin could achieve the function of anti-cancer via inducing cell apoptosis,however,the molecular mechanism of apoptosis induced by baicalin and whether baicalin could influence the cell growth,cell cycle,cell migration and invasion ability and stem cell characteristics is still not clear.In order to further reveal the effects of baicalin on colorectal cancer cells,we have done the following researches.First,baicalin could inhibit colorectal cancer cell activity and induce cell apoptosis.FHC,RKO,HCT116,SW480 cell were treated with 0,50,100,200,400,800 μg/mL baicalin and we found that the viability of colorectal cancer cells was decreased.DAPI staining and FCM results showed that baicalin could induce colorectal cancer cell apoptosis.In addition,Western Blot results showed that baicalin induced colorectal cancer cell apoptosis by Caspases/Parp-1 signaling pathway,rather than the p53 signaling pathway.Second,baicalin could inhibit colorectal cancer cell growth and adhesion.Colony formation assays and cell adhesion assays results showed that the clonogenic capacity and adhesion ability of colorectal cells were inhibited with the increasing concentrations of baicalin.Third,baicalin could induce colorectal cancer cell cycle arrest.Flow cytometry and western blot results showed that baicalin-induced G1-phase cell cycle arrest is due to modulating the expression of p-Akt,Cyclin D1,Cyclin E1 and CyclinB1in colorectal cancer cells.Fourth,baicalin could inhibit colorectal cancer cell migration and invasion.wound-healing assay and transwell assay results indicated that baicalin was effective in the prevention of colorectal cancer migration and invasion in in a dose-and time-dependent manner.Fifth,baicalin reversed epithelial to mesenchymal transition(EMT).Western Blot results showed that baicalin could inhibit the TGF-β1-induced epithelial mesenchymal transformation through suppression of TGF-β/Smad signaling pathway.Sixth,baicalin inhibits cancer stem cell growth,differentiation and self-renewal ability.Cancer stem cell sphere forming assay and western blot assay showed that baicalin could not only inhibit the growth of monolayer-cultured cell,but also inhibit the cell growth,differentiation and self-renewal ability of sphere cells in a dose-and time-dependent manner.In summary,all data indicated that baicalin could induce cell cycle arrest in G1 phase,reverse the TGF-β1-induced epithelial-mesenchymal transition,inhibit cell growth,and weakening the characteristics of cancer stem cell,and then induce cell apoptosis in colorectal cancer cells.Our results provide detailed theoretical basis for finding new targeting molecules and signaling pathways on clinical treatment of colorectal cancer,and provide reliable basis for baicalin as a clinical drug in the future treatment of patients with colorectal cancer.