Effect of c-Jun overexpression on potential of MCF-7 tumor liver metastases in nude mice. Mice were injected intravenously with 3 × 106 tumor cells in a volume of 200 μl via the lateral tail vein. The livers were autopsied 3–4 weeks post injection and tissues with metastases were photographed for gross morphology or processed for histology. A, the external image of multiple metastatic lesions of a liver. B, massive infiltration of the liver by MCF-7/c-Jun derived tumor cells observed by microscopic examination. C, no liver infiltration by parental cells was observed. ← liver tissue; ◀ metastasis ×400 magnification.