This evidence was confirmed in validation set. Next using all 104 patimets we found IHA positive FGF2 in stromal cells (FGF2-S) in 85 patients, and the radiotherapy-induced increase of FGF-S in 23 patients. Though positive FGF2-S in pretreatment samples was significantly related selleck with increased expression change of VEGF, it was not related with poor prognosis. Conclusion Radiation causes severing the normal or cancerous associations with adjacent cells and changes the extracellular matrix environment. Therefore, we need to investigate not only pretreatment status of tumors, but also modified

tumor structures during fractionated radiotherapy. In this study, we found FGF2-T expression change as a monitoring marker for the effectiveness of radiotherapy, and found the relationship between FGF2-S in pretreatment status and VEGF expression change in a subgroup of patients. Poster No. 14 The Membrane Mucin MUC4 and Its Partner Oncogenic Receptor ErbB2 Alter in Vitro and in Vivo Biological Properties of Human Pancreatic Tumor Cells Nicolas Jonckheere 1 , Nicolas Skrypek1, Nathalie Saint-Laurent2, Nicole Porchet1, Christiane Susini2, Isabelle van Seuningen1 1 Inserm U837/Jean-Pierre Aubert Research Center/Team 5 “Mucins, PARP inhibitor cancer Epithelial Differentiation and Carcinogenesis”, Lille, France, 2

Inserm U858/Institut de Médecine Moléculaire de Rangueil, Toulouse, France Rationale: Pancreatic cancer is one of the most deadly cancers in the world

with a very low (5%) survival rate at 5 years. Identification of new therapeutic targets and new biomarkers remains mandatory and will allow a better understanding of molecular mechanisms responsible for pancreatic tumor progression. The MUC4 membrane mucin is one marker candidate as it is not expressed in normal pancreas whereas it is neo-expressed as early as precursor stage of pancreatic intraepithelial neoplasia (PanIN) and constanttly increases during not the carcinogenetic sequence. Moreover, as an ErbB2 partner and target of TGF-b pathway, MUC4 actively participates in signalling pathways associated with tumor progression. Aim: To define the roles of both MUC4 and ErbB2 in pancreatic carcinogenesis in vitro and in vivo. Material and Methods: The human pancreatic adenocarcinomatous cell line CAPAN-2 was used to establish stable knocked-down (KD) cellular clones by a shRNA approach. Results: CAPAN-2 MUC4-KD clones have a proliferation defect compared to CAPAN-2 Mock clones expressing MUC4. Decrease of proliferation is correlated to a decrease in cyclin D1 expression whereas cell cycle inhibitor p27kip1 is not affected. CAPAN-2 MUC4-KD migration properties were reduced. Invasive properties were not altered. CAPAN-2 ErbB2-KD cellular clones have reduced proliferative and invasion properties. Moreover, we show that CAPAN-2 lacking MUC4 are more sensitive to chemotherapeutic drug gemcitabine.