Histologic features of representative parental human CRC tumors and their derivative xenografts in NSG mice.

<p>Each row in (A)–(C) comprises micrographs of tissue sections from a single parental human tumor or murine xenograft. (A) Left column: tissue sections stained with hematoxylin and eosin (H+E). Subsequent columns, from left to right: tissue sections stained for human leukocyte antigen class I (HLA-ABC), epithelial marker E-cadherin, mesenchymal marker vimentin, endothelial marker PECAM1, and T-cell marker CD3. The rows, from top to bottom, show the histologic features of parental human tumors from D61540, P2726, and P2750, paired with their first-generation xenografts. The histology of the stroma-predominant xenograft developed from P2726 ascites fluid is also shown in the fifth row; the white arrow in the E-cadherin micrograph in this row indicates a small focus of tumor cells. Arrowheads in the PECAM1 micrograph for the P2750.Tu.X1 xenograft indicate areas with PECAM-1-immunoreactive cells. All images were obtained at 200x magnification. White scale bar in the upper left micrograph represents 200 µm.