Effect of MBD1 siRNA on growth of pancreatic cancer cell line BxPC-3

Abstract

Objective To observe the effect of MBD1 siRNA on the growth of pancreatic cancer cell line BxPC-3, and explore the role of MBD1 in the carcinogenesis of the pancreatic carcinoma. Methods One siRNA sequence targeting MBD1 was designed by software and cloned into the expres-sion plasmid pGCsi-U6/Neo/GFP. DNA sequencing was used to confirm that the recombinant plasmid was constructed correctly. The constructed plasmid and the control plasmid were stably transfected in-to human pancreatic cancer cell line BxPC-3. RT-PCR and Western blot were used to detect the MBD1 mRNA and protein expression after RNA interference. The cell growth curve was measured by MTT assay. The three kind of cells (BxPC-3, BxPC-3/vector, BxPC-3/MBD1-siRNA) were injected subcu-taneously to nucle mice, which were observed for 8 weeks for tumor formation respectively. Results RT-PCR and Western blot showed that the MBD1 mRNA and protein expression were significantly lower in the BxPC-3/MBD1-siRNA group than in BxPC-3 and BxPC-3/veetor group (P<0. 01). In vivo and vitro, the growth of BxPC-3 cell was suppressed after transfected with MBD1 siRNA. The MBD1 mRNA in tumor of BxPC-3/MBD1-siRNA group could not De detected by RT-PCR. The mRNA levels of some tumor suppressor genes including CDH1 and RB were up-regulated significantly after RNA interference targeting MBD1. Conclusion The stable MBD1-siRNA recombinant plasmid can decrease MBD1 expression in human pancreatic cancer cell BxPC-3 and inhibit the growth of the cell notably in vivo and vitro, the mechanism is still unclear. MBD1 mediating transcriptional repres-sion may play an important part in the development of pancreatic cancer. Key words: Pancreatic neoplasms; Transfection; RNA interference; Tumor suppressor gene