Figure 4
From: Cell Death in MMTV-c-myc Transgenic Mouse Mammary Tumors May Not Be Typical Apoptosis
Ultrastructure of c-myc transgenic tumor tissue. According to their electron density, the tumor cells could be divided into two categories of dark cells and light cells (A). Most tumor cells show one or more giant nucleoli (A and B). Mitochondria (arrow) of the tumor cells show either electron-light (B and C) or electron-dark (D) amorphous matrix, with absent or very few cristae. When the cristae appear, they may be dilated to cavities with irregular shapes (arrow in D). Frequently, the malformed mitochondria are degenerated, characterized by lysis of matrix and cristate, leaving a hollow mitochondrial body (arrow in E). Macrophages appear frequently, especially in the places of dead cell islands (F and G). Every macrophage contains many phagosomes (arrowhead in F to J). Some phagosomes show very high electron density (H and J) or contain components with very high electron density (I). Many phagosomes could be as large as a nucleus (G), and some resemble the nucleus of engulfed cell (arrow in F). Note that in the place of dead cell islands (G), no tumor cells show condensed nucleus. Disruption of cell membrane and release of phagosomes is discerned in a macrophage (arrow in J).
