Objective:To investigate the influence and mechanism of bufalin-loaded Pluronic- polyetherimide(PEI)nanoparticles on the growth of colorectal cancer Lovo cells in vitro and vivo via miR-497 mediated IGF1-R-PI3K-Akt signaling pathway. MethodsThe colorectal adenocarcinoma Lovo cells were transfected by lentivirus miR-497. The effects of bufalin-loaded Pluronic-PEI nanoparticles on proliferation,invasion and metastasis of Lovo cells in vitro were observed,as well as the regulation on the related gene and protein in miR-497 mediated IGF1-R-PI3K-Akt signaling pathway. The orthotopic xenograft model of colorectal cancer was established in nude mice. The mice were sacrificed after 8 weeks,and the tumor formation was observed.  Results:①Compared with the control group,the proliferation inhibition rate of bufalin-loaded Pluronic-PEI nanoparticles on miR-497 overexpressed Lovo cells was the most significant and was increased in a time and dose dependent manner,and the apoptosis rate of miR-497 overexpressed Lovo cells was increased from (28.93±0.24)% to (75.20±0.29)%,which was significantly higher than that of the Lovo cells and Lovo NC cells treated with the same concentration(P<0.01). In the scratch assay,the migration rate of miR-497 overexpressed Lovo cells was decreased from (0.083±0.019)(25 nmol/L)to (-0.242±0.035)(400 nmol/L)in a dose-dependent manner. ②The Transwell assay showed that bufalin-loaded Pluronic-PEI nanoparticles at concentration of 25 nmol/L could significantly inhibit the invasion of miR-497 overexpressed Lovo cells. ③Western blot showed that the protein expressions of p-Akt Ser473 and p-Akt Thr308 in Lovo NC cells and miR-497 overexpressed Lovo cells were significantly decreased after the treatment with bufalin-loaded Pluronic-PEI nanoparticles and LY294002,but there was no obvious change on the expression of pan-Akt. ④In vivo experiments,the effects of bufalin-loaded Pluronic-PEI nanoparticles on inhibiting tumor metastasis were better than those of bufalin.  Conclusion:Bufalin-loaded Pluronic-PEI nanoparticles can inhibit the invasion and metastasis of colorectal cancer in vitro and vivo via miR-497 mediated IGF1-R-PI3K-Akt signaling pathway.