Alteration of tumor glucose metabolism after radiotherapy in MCF-7 breast cancer cell lines

Cancer cells utilize anaerobic glycolytic way to compensate their faster metabolism when compared to normal cells. The purpose of this study is to investigate the effect of radiation on tumor metabolism. MCF-7 breast cancer cell lines were divided into 4 groups, including 2 control groups and aerobic and anaerobic study groups (were irradiated 600 cGy by Co-60 teletherapy unit), incubated with radiolabelled glucose for 4 hours. One control group was for aerobic, and the other was for anaerobic group after KCN addition. Radiolabelled CO2 produced by the cells was isolated and collected in specially designed simulation vials. In supernatant the measurements of other end-products of carbohydrate catabolism including lactate, pyruvate, acetate were performed on a liquid scintillation analyzer after they were collected via anion-exchange chromatography. Finally glucose in supernatant was measured enzymatically by glucose oxidase method. Glycogen consumption and lactate production were significantly higher in anaerobic and radiation groups (p<0.01). Whereas CO2 production was significantly higher in control group (p<0.01). Taken all results together radiation lead tumor cells more anaerobic glycolysis with high glycogen consumption, high lactate production and low CO2 production. Radiation itself has led tumor cells to produce energy by anaerobic glycolysis, meaning radiation exposed cells become more hypoxic