Fig. 2. Prostate epithelial spheroids grown in Matrigel and KSFM plus 2% serum (sample C). A, phase image. Bar, 90 µm, the approximate diameter of one spheroid. B, TEM of a whole spheroid. Bar, 10 µm. C, high magnification TEM of a whole cell within the spheroid, showing luminal microvilli (mv), secretory vesicles (sv), and Golgi apparatus (g). Bar, 10 µm.