Effect of recombinant DNA methylferase 1 plasmid on the expression of tumor-associated gene in human colon cancer cell line / 中华消化杂志

ABSTRACT

Objective To analyze the effect of eukaryotic expression vector containing sense and antisense DNA methyltransferase (DNMT1) gene on the transcript level of tumor associated genes in human colon cancer cell line. Methods Recombinant plasmid, including sense DNMT1 (HMT) and antisense DNMT1 (THM) gene, were constructed and transfected into SW1116 cell by using the lipofectamine. Then G418 filtration was performed. The expression of DNMT1 protein was examined by Western blotting. The transcription level of hMLH1, hMSH2, c myc and p16 INK4A genes were detected by RT PCR. Results The sense and antisense eukaryotic expression vectors were successfully constructed and then the constructed recombinant plasmids were transfected into SW1116 cell. The protein levels of DNMT1 have been up regulated and down regulated in SW1116 cells transfected with HMT and THM plasmids, respectively. The mRNA level of hMLH1, hMSH2, c myc gene were down regulated in the sense DNMT1 transfected cell. The mRNA level of hMSH2 was up regulated in the antisense DNMT1 transfected cell. However, the transcription level of p16 INK4A gene could not be associated with DNMT1 in SW1116 cell.Conclusion DNMT1 can regulate the expression of the tumor associated genes in human colon cancer cell line SW1116.