Effect Of Mitogen-activated Protein Kinase MAP4K5 On The Biological Behaviors Of Gastric Cancer Cells

Objective: To investigate the expression of mitogen-activated protein kinase MAP4K5 in gastric cancer tissues and to explore its effects on the biological behavior of gastric cancer cells by overexpression and silencing MAP4K5.Methods: 1.The expression of MAP4K5 in gastric cancer tissues and adjacent normal tissues was detected by Western-blot,Real-time PCR and tissue microarray combined with immunohistochemistry.2.Constructing stable gastric cancer cell lines,including AGS and SNU-216, which MAP4K5 were over-expression or knockdown.Then the expression of MAP4K5 were validated by Western-blot.3.Functional assays,including cell wound-healing assay,Transwell cell migratio assay in vitro and Transwell cell invasion assay in vitro,CCK-8 kit,plate colony formation assay,soft agar colony formation assay,were implemented to identify the influence of MAP4K5 on the ability of migration、invasion and proliferation of gastric cancer cells.Results: 1.Among 186 matched gastric cancer tissues and adjacent normal tissues,the positive rate of MAP4K5 in gastric cancer tissues was 6.3%,and the positive rate in adjacent normal tissues was 62.4%.The difference was statistically significant(*,p<0.05).Other than this,the results of Western-blot and Real-time PCR showed that the protein and mRNA expression levels of MAP4K5 were lower in gastric cancer tissues than in adjacent normal tissues.2.Over-expression and knockdown MAP4K5 did not affect the ability of roliferation of AGS or SNU-216 cells as evaluated by CCK-8 assay,neither by late colony formation assay,or soft agar colony formation assay.In the cell ound-healing assay,the cell scratch area of the MAP4K5 overexpression roup was wider than that of the control group,while the knockdown group as narrower than the corresponding control group.The difference was tatistically significant(*,p<0.05).In the Transwell cell migration in vitro and nvasion in vitro assay,the number of cells in the overexpressed group cell icroporous membrane was decreased,while the number of microporous cells n the knockdown group was increased,the difference was statistically ignificant(*,p<0.05).Conclusion: 1.MAP4K5 was down-regulated in gastric cancer tissues.2.MAP4K5 can inhibit the migration and invasion of gastric cancer cells,but has o effect on its proliferation.