Different effects of the chemically similar foodborne flavonoids genistein, genistin, and daidzein on the inhibition of proliferation and induction of apoptosis in U251 glioma cells

Abstract Glioma is one of the most aggressive diseases among malignant tumors. Chemotherapy has a very important role in the treatment of glioma. However, most western medicines elicit different adverse reactions in patients along with obvious side effects. Therefore, there is a clinical need to develop new antitumor drugs with low toxicity and good therapeutic effects to reduce the mortality of cancer patients. The different effects of foodborne flavonoids genistein (GST), genistin (GIN), and daidzein (DAI) on glioma U251 cells have not been studied. Therefore, this study explored the effects of these flavonoids on U251 cells. CCK-8 assays, fluorescence microscopy, and flow cytometry were used to detect the different effects of flavonoids on the proliferation, morphology, and apoptosis of glioma U251 cells, respectively. Reverse transcription-PCR and western blotting were carried out to detect the expression of caspase-3, Bax, PI3K, mTOR, and AKT at mRNA and protein levels, respectively. U251 cell viability was reduced with treatment at different concentrations of GST, GIN, and DAI. GST and GIN promoted apoptosis by upregulating the expression of Bax and caspase-3, whereas DAI promoted apoptosis by downregulating p-AKT and p-mTOR. This study provides a theoretical basis for the use of flavonoids in the treatment of gliomas.