Objective To investigate the effect of over-expression of pituitary tumor transforming gene 1 (PTTG1) on the invasion and migration of human colon cancer cells SW480 and its possible mechanism.

Methods Both pcDNA3.1(+)-PTTG1and pcDNA3.1(+) plasmids were separately transfected into human colon cancer cell line SW480 by liposome transfection method and G418 was used to screen positive clones. Real-time PCR and Western blot were used to asses the stably over-expressed PTTG1 in PTTG1-SW480. The abilities of migration and invasion of PTTG1-SW480 cells were assayed by Transwell chambers and Western blot was used to detect the expression of MMP2,MMP9,E-cadherin,Vimentin and Snail.

Results (1) The cloned cells PTTG1-SW480 with PTTG1 over-expression were successfully obtained; (2) After PTTG1 over-expression,the abilities of migration and invasion of SW480 cells were enhanced,the expression of MMP2 and MMP9 were up-regulated,Vimentin and Snail expression were up-regulated,and E-cadherin expression was down-regulated (all P＜0.01) ; (3) The signaling pathway of PI3K/AKT activation was enhanced in PTTG1-SW480 cells. Interfering with LY29400,the abilities of migration and invasion and EMT of PTTG1-SW480 cells were prevented,the expression of E-cadherin was up-regulated and Vimentin and Snail expression were down-regulated (all P＜0.01) .

Conclusion  PTTG1 over-expression may promote SW480 cells migration and invasion through activating PI3K/AKT pathway to induce EMT. PTTG1 may become a potential target for colon cancer treatment.