Construction of MeTA-inducible system in pancreatic cancer cell lines as well as a normal pancreatic ductal cell line

In order to identify critical hypermethylated and silenced genes in cancer cells, we have developed the method called methyl-CpG targeted transcriptional activation (MeTA), which can globally reactivate hypermethylated genes in the genome. In MeTA, a fusion gene comprised of the MBD from MBD2 protein and the NFkB transcriptional activation domain (AD) is transfected into cancer cells.

Then MBD specifically binds to the promoter regions of hypermethylated genes, and NFkB (AD) recruits p300/CREB-binding protein (CBP) and reactivates epigenetically silenced genes. We have constructed a tetracycline-inducible NFkB (AD)-MBD (MeTA) expressing system using pancreatic cancer cell lines MIA PaCa-2, PK-1, and PK-9 as well as one normal pancreatic epithelial cell line HPDE. MeTA induction significantly suppressed cell growth and caused apoptosis in both PK-1 and PK-9.