OBJECTIVE To investigate the inhibitory effects of Bruceine A(BA)on colon cancer and its underlying mechanisms.METHODS Human colon cancer HT-29 and HCT116 cells were treated with various concentrations of BA(0,1,2,5,10,20,40,80 μmol·L-1).Cell viability was assessed using the Cell Counting Kit-8(CCK-8).Flow cytometry,wound healing assays,and Transwell assays were employed to evaluate the effects of BA on cell apoptosis,cell cycle,invasion,and migration.Mo-lecular docking simulations were used to assess the binding of BA to GSK-3β protein,and Western blot analysis was used to examine protein expression related to the cell cycle,epithelial-mesenchymal transition,and the Wnt/β-catenin signaling pathway.An HT-29 cell subcutaneous xenograft mouse model was established.After tumor formation,mice were randomly divided into three groups(six mice per group):a blank group,a low-dose BA group(0.1 mg·kg-1),and a high-dose BA group(0.2 mg·kg-1).Mice were ad-ministered the drug for 19 d,then sacrificed,and tumor tissues were collected.Tumor volume changes over time were observed;Ki67 immunohistochemistry was used to assess cell proliferation in tumor tissues;Western blot analysis of Wnt/β-catenin signaling pathway protein expression was conducted.RESULTS Compared with the blank group,BA could significantly inhibit the proliferation of HT-29 and HCT116 cells,with IC50 values of 10.80 μmol·L-1 and 17.96 μmol·L-1,respectively.Flow cytometry results showed that BA significantly induced apoptosis of HT-29 cells(P<0.01,P<0.001),and arrested the cell cycle at the S phase,accompanied by de-creased expression of cycle-related proteins CDK2 and Cyclin A(P<0.05,P<0.01,P<0.001).BA inhibited cell migration and in-vasion ability(P<0.05,P<0.01,P<0.001),reduced the expression of EMT-related proteins Snail,Vimentin,and N-Cadherin(P<0.01,P<0.001),and upregulated the expression of E-Cadherin protein.In addition,BA inhibited the expression of β-catenin and p-GSK3β proteins.Wnt agonist LiCl could significantly antagonize the anti-colon cancer effect of BA;Wnt inhibitor XAV939 could enhance the anti-colon cancer effect of BA.In the in vivo experiment,compared with the blank group,the tumor volume of the low-dose and high-dose BA groups was significantly reduced(P<0.05,P<0.001).Immunohistochemistry results showed that compared with the blank group,the expression of Ki67 in tumor tissues of the low-dose and high-dose BA groups was significantly reduced(P<0.001).Western blot results further proved that BA inhibited the Wnt/β-catenin signaling pathway.CONCLUSION BA inhibits the viability,invasion,and migration of colon cancer HT-29 cells,induces apoptosis,and causes cell cycle arrest.Additionally,it significantly suppresses the growth of subcutaneous HT-29 cell xenografts in vivo,possibly related to the Wnt/β-catenin signaling pathway.

OBJECTIVE To investigate the inhibitory effects of Bruceine A(BA)on colon cancer and its underlying mechanisms.METHODS Human colon cancer HT-29 and HCT116 cells were treated with various concentrations of BA(0,1,2,5,10,20,40,80 μmol·L-1).Cell viability was assessed using the Cell Counting Kit-8(CCK-8).Flow cytometry,wound healing assays,and Transwell assays were employed to evaluate the effects of BA on cell apoptosis,cell cycle,invasion,and migration.Mo-lecular docking simulations were used to assess the binding of BA to GSK-3β protein,and Western blot analysis was used to examine protein expression related to the cell cycle,epithelial-mesenchymal transition,and the Wnt/β-catenin signaling pathway.An HT-29 cell subcutaneous xenograft mouse model was established.After tumor formation,mice were randomly divided into three groups(six mice per group):a blank group,a low-dose BA group(0.1 mg·kg-1),and a high-dose BA group(0.2 mg·kg-1).Mice were ad-ministered the drug for 19 d,then sacrificed,and tumor tissues were collected.Tumor volume changes over time were observed;Ki67 immunohistochemistry was used to assess cell proliferation in tumor tissues;Western blot analysis of Wnt/β-catenin signaling pathway protein expression was conducted.RESULTS Compared with the blank group,BA could significantly inhibit the proliferation of HT-29 and HCT116 cells,with IC50 values of 10.80 μmol·L-1 and 17.96 μmol·L-1,respectively.Flow cytometry results showed that BA significantly induced apoptosis of HT-29 cells(P<0.01,P<0.001),and arrested the cell cycle at the S phase,accompanied by de-creased expression of cycle-related proteins CDK2 and Cyclin A(P<0.05,P<0.01,P<0.001).BA inhibited cell migration and in-vasion ability(P<0.05,P<0.01,P<0.001),reduced the expression of EMT-related proteins Snail,Vimentin,and N-Cadherin(P<0.01,P<0.001),and upregulated the expression of E-Cadherin protein.In addition,BA inhibited the expression of β-catenin and p-GSK3β proteins.Wnt agonist LiCl could significantly antagonize the anti-colon cancer effect of BA;Wnt inhibitor XAV939 could enhance the anti-colon cancer effect of BA.In the in vivo experiment,compared with the blank group,the tumor volume of the low-dose and high-dose BA groups was significantly reduced(P<0.05,P<0.001).Immunohistochemistry results showed that compared with the blank group,the expression of Ki67 in tumor tissues of the low-dose and high-dose BA groups was significantly reduced(P<0.001).Western blot results further proved that BA inhibited the Wnt/β-catenin signaling pathway.CONCLUSION BA inhibits the viability,invasion,and migration of colon cancer HT-29 cells,induces apoptosis,and causes cell cycle arrest.Additionally,it significantly suppresses the growth of subcutaneous HT-29 cell xenografts in vivo,possibly related to the Wnt/β-catenin signaling pathway.