Fig. 6

Subcellular Zn accumulation is subtype-specific in breast cancer cells. a Confocal micrographs illustrating labile Zn pools (FluoZin-3, green) in MCF10A, T47D and MDA-MB-231 cells (60× magnification). Images are presented with differential interference contrast over-lay. Scale bar = 20 μm. b Data represent mean FluoZin-3 fluorescence intensity/μg protein ± SEM, n = 3 samples/cell line, from 3 independent experiments. Asterisk indicates a significant difference from MCF10A cells, p < 0.05. c Cartoon depicting Zn transporters that are over-expressed (>1.4-fold) and subcellular Zn pools that are increased in T47D cells (a model of Luminal breast cancer) and MDA-MB-231 cells (a model of Basal breast cancer) compared to non-tumorigenic MCF10A cells. d Representative images (5× magnification) of sections (5 μm) of non-malignant breast tissue and human tumors from two different women stained with hematoxylin and eosin (H&E; iii, v, vii, ix) and visualized by light microscopy (10× magnification); serial sections were immunostained for ZnT2 (iv, vi, viii, x). Negative controls were treated similarly but incubated with normal rabbit IgG. Malignant regions are noted in boxes in both H&E and immunofluorescent images. Scale bar =100 μm)