Difference in cell death response between mitomycin C and 5-fluorouracil treatment studied using quartz crystal microbalance combined with simultaneous monitoring of viable cells.

A quartz crystal microbalance (QCM) can be used to evaluate the physical properties of cells exposed to anticancer drugs. Mass-sensing techniques on electrodes detect subtle changes in adherent cells during drug treatment, providing insights into physiological, biochemical, and morphological events from a physical perspective. Although these methods have been established in many studies using living cells, their drug responses remain associated with cell viability. This study aimed to measure QCM response by simultaneously monitoring non-viable cell images. Treatment with mitomycin C (MMC) caused the resonant frequency to shift from a decrease to an increase, followed by a delayed rise in the proportion of non-viable cells. By contrast, treatment with 5-fluorouracil (5-FU) produced minimal frequency changes, accompanied by a shorter delay before cell death was observed. The fitting data to the model equations of the cumulative log-normal distribution curve showed a clear difference in parameter values between MMC and 5-FU, indicating distinct cell death processes. These results demonstrate that QCM-based monitoring of physical properties provides complementary information on drug responses and may serve as a useful tool in anticancer drug development.