Chemotherapeutic potential of matcha green tea (Camellia sinensis) polyphenols to induce cell-cycle arrest and apoptosis in WERI-Rb-1 retinoblastoma cells

Abstract

IntroductionCamellia sinensis has been used as a traditional medicine in Southeast Asia to treat various diseases for centuries. However, their efficacy against retinoblastoma has not been thoroughly investigated and characterized. This study aims to determine the cytotoxicity, cell cycle, and apoptotic induction by matcha green tea extract (MGTE) on retinoblastoma cancer cell lines. MethodsThe cytotoxic activity of MGTE was evaluated using MTT assay, and the morphology of cells was observed by fluorescence microscopy. Apoptosis and cell-cycle distribution were determined by propidium iodide (PI) and Annexin V staining, further analyzed through flow cytometry. The effect of MGTE on gene expression of MGTE-treated WERI-Rb-1 cells was investigated using quantitative polymerase chain reaction (qPCR) analysis. ResultsThe results showed that MGTE possessed high cytotoxic activity on WERI-Rb-1 human retinoblastoma cells with IC50 13.3 ± 1.40 µg/mL at 72 h. Flow cytometry results also proved that MGTE induced apoptotic cell death in the sub G0 phase. It was also observed that the chemotherapeutic effect of MGTE occurred via extrinsic and intrinsic apoptosis pathway that was mediated by the activation of caspase 3, caspase 8, caspase 9, Bad, and Bax, which culminated in the apoptosis of retinoblastoma cancer cells. ConclusionThis study suggests that matcha green tea could be used as an apoptosis-inducing anticancer agent for retinoblastoma cancer treatment, with further rigorous studies. The promising baseline information on the chemotherapeutic potential of MGTE provides a potential strategy for shedding light on retinoblastoma treatment.