Fibroblast activation protein and focal adhesion kinase: novel stromal therapeutic targets in pancreatic adenocarcinoma.

4094 Background: Fibroblast activation protein (FAP) is a serine protease expressed on tumor stromal fibroblasts which results in tumor growth potentiation. Focal adhesion kinase (FAK) is a protein tyrosine kinase which promotes cell growth and migration through the extracellular matrix. Given the extensive desmoplasia characteristic of pancreatic adenocarcinoma, we hypothesized that FAP and FAK would be overexpressed in pancreatic cancer and contribute to poor outcome. Methods: Twenty-nine paraffin-embedded pancreatic adenocarcinoma specimens from patients undergoing curative resection were obtained from the Fox Chase Cancer Center tumor bank. Four samples (2 normal and 2 mucinous borderline tumors) served as controls. FAP and FAK expression was assessed by immunohistochemistry and graded by staining extent (%) and intensity (0–3+). Results: Ninety percent of tumor specimens (26/29) expressed FAP in either fibroblasts surrounding tumor (FST), surrounding stroma (SS), or tumor. The highest expression leve...