Figure 4.

Representative H & E stained histological section of our rat cholangiocarcinoma cell line BDEsp-TDE at in vitro passage 3, derived from well differentiated BDEsp ICC, and cultured alone for 11 days within rat tail type I collagen gel matrix. Note that the cholangiocarcinoma cells are organized into well differentiated “duct-like” structures reminiscent of those observed in histological sections of the parent low grade BDE ICC. For comparison, the photomicrograph in (B) demonstrates a rat cholangiocarcinoma cell line designated as BDEneu-TDE that was established in our laboratory from a more highly malignant and moderately-differentiated ICC formed in syngeneic rat liver after bile duct inoculation of oncogenic-neu transformed rat cholangiocytes. As demonstrated in B, rat BDEneu-TDE cells in organotypic culture in a type I collagen gel matrix reflect the less differentiated “duct-Like” phenotype of the parent orthotopic tumor. In both A & B, arrows point to dead cells within the lumens of some of the neoplastic “duct-like” structures, indicating that cells within the central areas of formed cholangiocarcinoma cell spheroids are likely undergoing apoptotic cell death.