The Effect Of Phloretin On The Hippo-YAP Pathway And Its Effect On The Growth Of HepG2 Cells

Objective:The purpose of our study is to verify whether phloretin can influence the growth of HepG2 cells by acting on the Hippo-YAP pathways.Methods:The expression of YAP mRNA and protein are detected by RT-PCR and western blotting respectively;the transcriptional activity of YAP is detected with a luciferase reporter;the expression and the spatial location of YAP protein are detected by immunofluorescence confocal.Cell viability is detected by morphological observation,MTT assay and colony formation assay;Tumor invasion assay is used to detect the effect of the invasion of HepG2 cells.Result:The expression of YAP mRNA,protein,transcriptional activity and nuclear translocation of YAP are inhibited significantly by phloretin.The expression of p-YAP protein is increased.The oncogenes CTGF and CYR61 as downstream transcriptional targets of YAP are reduced by phloretin.The morphology of treated cells become rounded,detached from the culture flask and suspended in the liquid culture under the inverted light microscope.We find that the inhibition of phloretin is dose-dependent with drug concentration,and overexpression of YAP can weaken this effect significantly.The cell invasion is reduced when concentration of phloretin increased.TAZ and TEAD are also important genes of Hippo-YAP pathways,and related to the formation of tumors.Phloretin can inhibit the expression of TAZ and TEAD.Conclusion:Our findings strongly indicated that phloretin can through inhibiting YAP expression and nuclear localization to inhibit the growth of HepG2 cells.