Objectives: RNA interference, an indispensable tool in functional genomics, can be induced by small interfering RNAs (siRNAs). Because of the transient nature of siRNA-mediated RNA interference, the continuous use of transfection reagents is mandatory. Because transfection reagents are expensive, cost-effective alternatives must be considered. In this study, we describe a polyethylenimine-based siRNA transfection protocol for pancreatic cancer cell lines.
Methods: For determination of polyethylenimine-based transfection efficiency, a FAM-labeled siRNA was transfected into several pancreatic cancer cell lines and subsequently analyzed by flow cytometry. The effective knockdown of 2 siRNAs was determined on the protein level by Western blot. Toxicity of the transfection reagent was analyzed by viability assays.
Results: Polyethylenimine can be used without overt cellular morphological changes, and toxicity is negligible in human and murine pancreatic cancer cell lines. Transfection efficiencies ranged between 83% and 98% in the cell lines used. The knockdown at the protein level was comparable to commercially available transfection reagents. Polyethylenimine and siRNA concentrations, incubation time, and cell density are determinates of the transfection efficiency.
Conclusions: Polyethylenimine is a suitable and cost-effective alternative for transfecting siRNAs into pancreatic cancer cells.