Room: Exhibit Hall | Forum 9
Purpose: Hypoxia in the tumor microenvironmentsÂ is a well-known indicatorÂ ofÂ poor patient prognosis and limits therapeutic success;Â however,Â itsÂ complicated spatial and temporal kineticsÂ are not well understood. To study these temporal effects in vitro, we quantified intercellular hypoxia for two murine breast cancer cell lines 4T07 and E0771 using oxygen-sensing duel-emissive boron nanoparticles (BNP). We hypothesized that, after irradiation, the cell line with the higher oxygen consumption rate, 4T07, exhibits an increased hypoxic effect over time after irradiation.
Methods: Boron nanoparticles dual-emit a constant fluorescent peak and a phosphorescent peak that is dependent on oxygen concentrations due to collisional quenching. Using optical microscopy, we can quantify these ratiometric changes in intensity. To test our hypothesis, we irradiated the cells at their 50% survival dose. Immediately after irradiation, we added the BNP and measured the intensity over time.
Results: We found that the BNP could detect minute environmental changes in hypoxia over time for both cell lines when compared to their unirradiated controls. 4T07 exhibited a significantly smaller amount of oxygen in its solution compared to E0771 at earlier time points.
Conclusion: Based on our results, we can begin to build a quantitative model of the temporal kinetics of hypoxia for E0771 and 4T07. With this information, we will extend our study to in vivo murine models where we can continue to quantify the temporal effects of hypoxia on tumor cells after irradiation.
Not Applicable / None Entered.