Thursday, March 22, 2012: 10:45 a.m. - 12:15 p.m.
Presentation Type: Oral Session
Objectives: In the present study, we developed a novel histology-based 3D reconstruction technology to simultaneously inspect the invasive tumor foci and surrounding vascular architecture. Methods: In practice, we prepared over 100 paraffin-embedded serial sections (4µm thick) from a core biopsy of 3mm in diameter that was dissected out of the invasion front of tongue squamous cell carcinoma. Antibodies used were: cytokeratin cocktail for cancer cell labeling, CD31, CD34 and CD105 for assignment of subpopulation of blood endothelial cells, and Ki-67 for proliferation activity. A set of the serial sections were immunostained stepwisely with each of the antibodies in a combination of discrete color agents and the resulting RGB images were acquired using a virtual microscope (NanoZoomer, Hamamatsu Photonics). Image registration and segmentation for 3D reconstruction were automated with the aid of Ratoc TRI-SRF2 software to avoid operator-dependent subjectivity. Results: The present 3D analysis of the tumor microenvironment proved the divergent vascular densities in intra- and peri-tumor regions, aberrant divergence and tortuosity of tumor vessels, and high frequencies (>104 sites/mm3) of spatial association between carcinoma cells and blood endothelial cells. The endothelial cell population was assigned and divided into subpopulations depending on their phenotypic criteria, such as the single-positive, double-positive and triple-positive in the vascular wall for CD31, CD34 and CD105. Most abundant subpopulations of the endothelial cells were the CD31-positive cells including double- and triple-positive, followed by CD34-single-positive cells, and much less in CD105-single-positive cells that were integrated preferentially at the capillary edge in the intratumor region. Conclusions: The overall results of 3D inspection provide evidence for the loco-regional morphological heterogeneity of tumor vascular wall architecture and endothelial cell subpopulations in the tumor microenvironment. These findings also suggest a remarkable degree of phenotypic plasticity in cancer vasculature systems. Supported by Grants-in-Aid from MEXT/JSPS of Japan.This abstract is based on research that was funded entirely or partially by an outside source: Supported by Grants-in-Aid from MEXT/JSPS of Japan
Keywords: Carcinogenesis, Digital image analysis, Human, Pathology and Tongue