Circadian Rhythms and Breast Cancer: The Role of Per2 in Doxorubicin-Induced Cell Death

Figure 2

Determination of Per2 localization. Both MCF-12A and MDA-MB-231 cells were cultured under standard control cellular conditions in 8-well chamber plates for a period of 24 hours. Cells were immunostained for Per2 (Green) and Hoechst 33342 (Blue) and visualized using fluorescent confocal microscopy at a 63x magnification. Two distinct populations of Per2 localization were observed in both the MCF-12A and MDA-MB-231 cell lines: (a) Per2 nuclear localization was seen in the fluorescently dimmer cell populations; MCF-12A cells show slight nuclear localization; however this was more prominent within the MDA-MB-231 breast cancer cells. White arrows indicate nuclear localization of Per2. (b) Per2 was localized exclusively within the cytoplasm of the fluorescently brighter cell population in both cell lines.

(a)

(b)