[Toxicity of cationic liposome Lipofectamine 2000 in human pancreatic cancer Capan-2 cells].
ABSTRACT To investigate the toxicity of cationic liposome Lipofectamine 2000 (Lipo) in human pancreatic cancer Capan-2 cells.
Capan-2 cells were cultured in the presence of Lipo at toxic concentrations, and the cell growth, apoptosis and cell cycle changes were evaluated by cell counting and flow cytometry.
The concentrations of both Lipo and siRNA affected the transfection efficiency. In a transfection volume of 2 ml, the presence of 5 microl Lipo resulted in slowed growth of Capan-2 cells, which was especially obvious after 3 days (P<0.001). Prolonged culture of the transfected cells caused significant increases in early apoptotic cells (P<0.05) and in the damaged or necrotic cells (P<0.001), and resulted in reduced viable cells (P<0.01); these changes became obvious after a 48-hour culture, which also increased the ratio of G(0)/G(1) phase cells (P<0.05) and decreased those of G(2)/M phase cells (P<0.01), S phase cells (P<0.01), and the late apoptotic cells (P<0.05).
Toxic concentrations of Lipo can affect the growth, apoptosis and cell cycles of Capan-2 cells in vitro, and this urges careful concentration selection when using Lipo for gene transfer into different cells.
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