Figure 4. Stroma decreases spheroid size by decreasing cell width.

(A) The diameter of 3D BPH-1 acini was measured in the presence or absence of stroma after 7 days in culture. Fifty acini cultured with stroma and 50 cultured without stroma were measured at mid-sections. The data represents five separate experiments, which were performed with different stromal cultures and Matrigel batches. (B) The number of cells within BPH-1 acini cultured with and without stroma were counted, according to Pearson et al. [22]. The cells from 10 spheroids were counted per condition and the experiment was repeated twice. (C) The width of individual cells within acini were measured at the mid-point of the cell (Ci) and at the basal edge of the cell (Cii). The length of individual cells was measured at their longest point (Ciii). Fifty cells were measured from a minimum of 10 spheroids per condition. The data represents three experiments, ***p<0.0005, **p<0.005, *p<0.05 (paired t-test).