ABSTRACT
Objective To investigate the role of bone marrow mesenchymal stem cells (BM-MSCs) in the invasion and metastasis of gastric cancer cells and to explore its mechanism.Methods SGC7901 and KATO-Ⅲ gastric cancer cells were co-cultured with BM-MSCs respectively,and the invasion ability of SGC7901 and KATO-Ⅲ gastric cancer cells were detected by Transwell assay.Secondly,CD133 + and CD133-cells were sorted from KATO-Ⅲ gastric cancers and co-cultured with BM-MSCs respectively to compare their changes in invasiveness.Meanwhile,the expressions of p-AKT and epithelial-mesenchymal transition (EMT) relative factors in gastric cancer cells were detected by Western-blot.The role of CD133 in BM-MSCs affecting the ability of invasion of gastric cancer cells was further vertified by the overexpression of CD133 in SGC7901 cells.SPSS17.0 software was used for statistical processing,and the stand deviation of the measurement data were expressed as the standard deviation,independent sample t test was conducted.Results The invasiveness of co-cultured SGC7901 and KATO-Ⅲ cells was significantly enhanced.The invasive ability of KATO-Ⅲ CD133+ cells co-cultured with BM-MSCs tended to increase more significantly than that of co-cultured CD133 cells[(259.0 ± 24.0)vs (58.0 ±5.6),P ＜ 0.001].The expressions of p-AKT,Snail and N-cadherin were significantly increased in co-cultured CD133+ cells (P =0.003,P =0.003,P =0.002),while the expression of E-cadherin was reduced (P =0.021).After co-cultured with BM-MSCs,the expression of E-cadherin was also reduced in CD133-cells (P =0.005),but the expressions of p-AKT,Snail and N-cadherin were no significantly changes (P =0.744,P =0.277,P =0.295).SGC7901 co-cultured with BM-MSC after overexpression of CD133 showed higher i nvasiveness than blank control group[(239.3 ± 24.0) vs (103.3 ± 15.5),P ＜ 0.001].The expressions of p-AKT,Snail and N-cadherin were significantly increased when co-cultured with BM-MSCs in the group of CD133 overexpression (P =0.001,P =0.001,P =0.001),while the expression of E-cadherin was significantly decreased(P =0.003).The expressions of Snail and N-cadherin were also significantly increased after co-cultured with BM-MSCs in the blank control group (P =0.001,P =0.004),and the expression of E-cadherin was significantly decreased (P =0.018),while the expression of p-AKT was not significantly changed (P =0.193).Conclusions BM-MSCs can enhance the invasion and metastasis of gastric cancer cells by promoting the EMT of gastric cancer cells.CD133 may be involved in the regulation of EMT in gastric cancer cells through the PI3K/AKT signaling pathway.
ABSTRACT
Objective To investitate the efficacy of cannabinoid-2 receptor (CB2R) activation in preventing liver ischemia-reperfusion (I/R) injury in mice.Methods Forty-eight male C57BL/6J mice,weighing 20-30 g,were divided into 4 groups (n =12 each):sham operation group (group S),group I/R,CB2R agonist JWH133 group (group J),and CB2R agonist JWH133 + CB2R antagonist SR144528 group (group JS).Liver I/ R was produced by blocking the hepatic artery and portal vein for 30 min followed by 45 min of reperfusion in anesthetized mice.At 60 min before ischemia,JWH133 20 mg/kg was injected intraperitoneally in group J,and JWH133 20 mg/kg and SR144528 30 mg/kg were injected intraperitoneally in group JS.The liver was removed at 45 min of reperfusion for determination of tumor necrosis factor-α (TNF-α),macrophage inflammatory protein-1α (MIP-1α) and MIP-2 contents (using ELISA),and expression of TNF-α,MIP-1α,MIP-2 and intercellular adhesion molecule-1 (ICAM-1) mRNA (by RT-PCR) in the liver tissues and for microscopic examination of the pathological changes.Results Compared with group S,the contents of TNF-α,MIP-1α and MIP-2 were significantly increased,and the expression of TNF-α,MIP-1α,MIP-2 and ICAM-1 mRNA was up-regulated in J and JS groups.Compared with group I/R,the contents of TNF-α,MIP-1α and MIP-2 were significantly decreased,and the expression of TNF-α,MIP-1α,MIP-2 and ICAM-1 mRNA was down-regulated in J group,and no significant change was found in the parameters mentioned above in JS group.Compared with group J,the contents ofTNF-α,MIP-1α and MIP-2 were significantly increased,and the expression of TNF-α,MIP-1α,MIP-2 and ICAM-1 mRNA was up-regulated in JS group.The pathological changes of liver tissues were significantly attenuated in group J as compared with I/R and JS groups.Conclusion CB2R activation is effective in preventing liver I/R injury in mice and the mechanism is related to inhibitioni of inflammatory responses in liver tissues.