Effects of GNP and its derivatives on apoptosis and cell cycle arrest in Panc-1 cells.

<p>Cells apoptosis induced by GNP and its derivatives was analyzed using the annexin V (FITC)/PI binding assay by flow cytometry. The values are the means (±SE) of three independent experiments. Statistical analysis was performed by comparing the annexin V and PI indexes in cells that were treated with GNP and its derivatives with those in cells in the control group (*p<0.05, **p<0.01, and ***p<0.001). (B) Panc-1 cells morphology was analyzed using a microscope (magnification, 400×) after the cells were treated with GNP and its derivatives. The cells treated with GNP, 10-GNP1 and 10-GNP2 exhibited several characteristic morphological changes, including the appearance of more rounded, shrunken, and suspended cells. In contrast, the morphologies of those treated with 1-GNP1 and 1-GNP2 were normal, with round and homogeneous nuclei similar to those observed in Panc-1 cells that were cultured in control medium. (C) The effects of GNP and its derivatives on Panc-1 cell cycle progression were determined by flow cytometric analysis. The values are the mean (±SE) of three independent experiments. Following treatment with GNP or 10-GNP2, the percentage of cells at G₂/M was significantly increased compared with control cells; this effect was accompanied by a significant decrease in the percentage of G₁ cells (*** p<0.001). (D) Morphological changes in cell nuclei and chromosomes were observed by Hoechst 33258 staining and fluorescence microscopy (magnification, 200×).