Recruitment of ER induces a dynamic remodeling of the actin cytoskeleton and of the cell membrane in T47-D breast cancer cells.

<p>A) T47-D cells were treated for different times with E2 (10 nM). Actin fibers were stained with phalloidin linked to Texas Red (red labeling) and nuclei were counterstained with DAPI (blue labeling). Immunofluorescent analysis reveals the dynamic modifications of actin fibers through the time-course and the formation of specialized cell membrane structures. Green arrows indicate longitudinal fibers; light blue arrows indicate membrane ruffles; yellow arrows indicate pseudopodia. Rectangles indicate the analyzed area which was demonstrated by the corresponding upper graph. In the graph, the longitudinal axis represents the gray level and the horizontal axis indicates pixels. Yellow, red and blue areas indicate the extracellular, plasma membrane and cytoplasmic fraction, respectively. B and C) Analytic results obtained by using Leica QWin image analysis and processing software showing the mean thickness of the cell membrane as well as the intensity of actin staining in the cytoplasm, membrane or extracellular compartment after treatment with E2 (10 nM) for different times. The results are derived from the sampling of five areas of the cell membrane of thirty different random cells. The areas of minimum and maximum cell membrane thickness were always included. The results are the mean±SD of the measurements. In C) * = p<0.05 vs. Basal condition (0 min).