Objective：To investigate the effects of 5-aza-2′-deoxycytidine (5-Aza-dC) and trichostatin A (TSA) on the methylation and expression of TFPI-2 gene in pancreatic cancer Panc-1 cells.
Methods：Panc-1 cells were treated with 5-Aza-dC alone, TSA alone and their combination. Methylation specific PCR (MSP), RT-PCR and Western Blot were used to determine the DNA methylation in promoter region, mRNA and protein expression of TFPI-2, respectively.
Results：After treatment with 5-Aza-dC alone or the combination of 5-Aza-dC and TSA, the hypermethylation of TFPI-2 gene in Panc-1 cells was reversed to an unmethylated pattern; the TFPI-2 mRNA and protein that did not express before treatment were reexpressed in Panc-1 cells; the TFPI-2 mRNA expression level was 0.821±0.050 and 0.887±0.042, and TFPI-2 protein expression level was 0.613±0.092 and 0.712±0.059, respectively. The effects of the two treatments (B5-Aza-dC alone and 5-Aza-dC plus TSA) were similar. However, no reversion of the hypermethylation status and no reexpression of TFPI-2 gene were noted in the Panc-1 cells treated with TSA alone.
Conclusions：The methylation of promoter region is a main cause of transcriptional inactivation of TFPI-2 gene in Panc-1 cells. Either 5-Aza-dC alone or 5-Aza-dC plus TSA can reverse the hypermethylation status of TFPI-2 gene and reexpress TFPI-2 in Panc-1 cells. However, TSA alone has no reverse effect on the inhibited TFPI-2 gene.