The expression of Fibroblast Activation Protein in human colon carcinoma

9668 Background: Human Fibroblast Activation Protein (FAP)/seprase is a 97-kd surface glycoprotein with dipeptidyl peptidase and gelatinolytic activity expressed on tumor associated fibroblasts in the majority of epithelial cancers including colon adenocarcinomas. FAP overexpression has been shown to promote tumor growth in animal models, and clinical trials targeting FAP enzymatic activity have been initiated. The primary objective of this study was to evaluate expression levels of FAP in human colon cancers by immunohistochemisty and relate its expression to clinical outcome. Methods: Sections of paraffin-embedded resected primary human colon cancer specimens from 1996 through 2001 within the Fox Chase Cancer Center tumor bank were stained with D8 antibody directed against FAP/seprase. Grading of staining was performed by assessment of FAP staining intensity (none, light, medium, dark) and overall percent of stromal staining (0, 1–10%, 11–50%, 51%+) as previously established. Survival time and time to r...