Inhibitory effect of curcumin on tumor growth in colorectal cancer mice and its mechanism of PTEN/PI3K/Akt signaling pathwayPEI Yongbin， WANG Guiqi， LI Wei， JIANG Xia， JIANG Haibo， ZHAO Zengren （Department of General Surgery，First Hospital，Hebei Medical University， Shijiazhuang 050031，China）