Demonstrating drug treatment efficacies by monitoring superoxide dynamics in human lung cancer cells with time-lapse fluorescence microscopy

Metformin hydrochloride, an antihyperglycemic agent, and sulindac, a nonsteroidal anti-inflammatory drug, are FDA-approved drugs known to exert anticancer effects. Previous studies demonstrated sulindac and metformin’s anticancer properties through mitochondrial dysfunction and inhibition of mitochondrial electron transport chain (ETC) complex I, as well as key signaling pathways. In this study, various drugs were adminsitered to A549 lung cancer cells, and results revealed that a combination of sulindac and metformin enhanced cell death compared to administration of the drugs separately. To measure superoxide production over time, we employed a time-lapse fluorescence imaging technique using mitochondrial-targeted hydroethidine. Fluorescence microscopy data showed largest increases in superoxide production in the combination treatment of metformin and sulindac. Results showed significant differences between the combined drug treatment and control groups, as well as between the positive control and control groups. This approach can be utilized to quantify anticancer efficacy of drugs, creating possibilities for additional therapeutic options.