ABSTRACT
AIM:To investigate the expression of long non-coding RNA maternally expressed gene 3 (MEG3) in colorectal cancer ( CRC) cells, and to observe the effect of MEG 3 on the invasion and migration of CRC cells .METH-ODS:The levels of MEG3 in human normal colon cell NCM 460 and CRC cells SW48 and LoVo were detected by real-time PCR.MEG3 was over-expressed by plasmid transfection , and the effects of MEG 3 on the invasion and migration of SW 48 and LoVo cells were analyzed by Transwell assay and wound healing assay .The expression of matrix metalloproteinase ( MMP) family proteins was determined by Western blotting .RESULTS:The level of MEG3 was down-regulated in CRC cells compared with normal colon cell NCM 460.The invasion and migration of CRC cells were reduced after MEG 3 over-ex-pression.Transwell invasion and migration assays showed that the numbers of transmembrane SW 48 and LoVo cells were smaller in MEG3 over-expression group than control group (P<0.05).The cell spaces were broader after MEG3 over-ex-pression in the wound healing assay , indicating that MEG3 over-expression inhibited the mobility of CRC cells .Meanwhile, over-expression of MEG3 reduced the expression of MMP-2 and MMP-9, and elevated the expression of tissue inhibitor of metalloproteinase-2 (TIMP-2).CONCLUSION:The expression of MEG3 is down-regulated in CRC cells.Over-expres-sion of MEG3 inhibits the invasion and migration of CRC cells .TIMP-2, MMP-2 and MMP-9 might play an important role in this regulation .