Objective: To investigate the effect of cinnamaldehyde on transforming growth factor-β1(TGF-β1)-induced proliferation

metastasis and epithelial-mesenchymal transition (EMT) of human colorectal carcinoma cells LoVo and explore its relationship with phosphatidylinositol 3 kinase/protein kinase B (PI3K/Akt) signaling pathway.Method: TGF-β1 was used to induce EMT of human colorectal carcinoma cells LoVo

and then different concentrations of cinnamaldehyde (0

20

40

80 mg · L-1) were used to intervene the TGF-β1-induced cells proliferation. The effect of cinnamaldehyde on cell proliferation was measured by methylthiazolyldiphenyl-tetrazolium bromide (MTT) assay. Transwell assay was used to observe the changes in invasive ability of cells

and Western blot was used to analyze the expression levels of epithelial phenotype marker protein E-cadherin

N-cadherin

Vimentin and key protein of phosphatidylinositol-3-kinases/proteinkinase B (PI3K/Akt) signaling pathway. PI3K/Akt inhibitor LY290004 was used to verify the cinnamaldehyde effect in inhibiting TGF-β1-induced EMT through the PI3K/Akt signaling pathway.Result: As compared with blank controls

cinnamaldehyde effectively inhibited TGF-β1-induced proliferation and invasion ability(P < 0.01)

significantly increased the expression of E-cadherin

decrease the expression of N-cadherin

Vimentin

stimulated by TGF-β1(P<0.01)

and meanwhile

it could reverse the expression TGF-β1-induced EMT through inhibiting the activation of the PI3K/Akt signaling pathway(P<0.01).Conclusion: Cinnamaldehyde can inhibit TGF-β1-induced proliferation

metastasis of colorectal carcinoma cells LoVo

and the mechanism may be associated with PI3K/Akt signaling pathway.