Objective        To investigate the effect of downregulation of LAT1 on the proliferation

migration

and invasion of SGC7901 cells.       Methods        Two sets of shRNA targeting LAT1 and one scramble shRNA were synthesized and inserted into pGPU6/GFP/Neo plasmid vectors

respectively. Then the recombinant plasmids containing the shRNAs were transferred into SGC7901 cells and the knockdown efficiency was deter

mined by using RT-PCR and Western blotting to detect the mRNA and protein expression levels of LAT1 and CD98hc

which forms the heterodimer with LAT1. The cells with higher knockdown efficiency were subjected to a subsequent selection using G418 to establish stable cell lines with constitutive lower expression of LAT1 compared with the cells transfected with the recombinant plasmids containing scramble shRNA. MTT assay

flow cytometry

and Transwell assay were conducted to determine the potency of proliferation

cell cycle

migration and invasion of SGC7901 cells.       Results        The sequences of LAT1-shRNA recombinant plasmids were identified by restriction endonuclease analysis and DNA sequencing. The mRNA and protein levels of LAT1 in SGC7901 cells decreased after LAT1-shRNA1 and LAT1-shRNA2 transfection for 48 h compared with the cells with scramble shRNA transfection. LAT-shRNA2 had higher knockdown efficiency than LAT-shRNA1 did. However

the expression of CD98hc was not affected. Downregulation of LAT1 inhibited the proliferation

migration and invasion of SGC7901 cells (P0.05). Flow cytometry showed SGC7901 cells were arrested in G

0

/G

1

phase.       Conclusion      Downregulation of LAT1 inhibits the proliferation

migration and invasion of SGC7901 cells. LAT1 plays an important role in the proliferation

migration and invasion of gastric cancer cells.