Anticancer Effects of Gingerol in Retinoblastoma Cancer Cells (RB355 Cell Line) Are Mediated via Apoptosis Induction, Cell Cycle Arrest and Upregulation of PI3K/Akt Signaling Pathway

BACKGROUND: The main aim of the current investigation was to study the antiproliferative activity of gingerol in RB355 human retinoblastoma cancer cells. The effects of gingerol on apoptosis induction, cell cycle arrest, and PI3K/Akt signaling pathway were also evaluated. MATERIAL/METHODS: MTT cell viability assay was used to assess the cytotoxic effects of gingerol in these cells while. To study apoptotic effects in these cells, we used inverted microscopy along with fluorescence microscopy using acridine orange/propidium iodide and Hoechst 33258 as staining dyes. Flow cytometry was used to study cell cycle phase distribution and Western blot assay indicated effects on PI3K/Akt protein expression levels. RESULTS: Results showed that gingerol exerted dose-dependent and time-dependent growth inhibitory effects in these retinoblastoma cells. However, the growth inhibitory effects of gingerol were less pronounced against normal fr2 cells. As compared to the untreated control cells, gingerol-treated cells at concentrations of 25, 75, and 150 μM had drastic changes in cell morphology, including rounding and withering of cells, with disorganized cell layers. Gingerol-treated cells exhibited bright fluorescence, indicating rupture of the cell membrane. These results were further confirmed by acridine orange/propidium iodide staining, in which untreated cells showed normal green fluorescence and gingerol-treated cells showed yellow/red fluorescence. Gingerol also led to dose-dependent G2/M phase cell cycle arrest in RB355 retinoblastoma cells, as well as concentration-dependent activation of PI3K-related protein expressions. CONCLUSIONS: Gingerol exhibits potent anticancer effects in RB355 human retinoblastoma cancer cells and these effects were mediated via apoptosis induction, cell cycle arrest, and modulation of the PI3K/Akt signaling pathway.