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Patients with pancreatic cancer frequently suffer from thrombosis due to excess thrombin generation. Yet, the effects of thrombin on pancreatic cancer are still poorly understood. The thrombin receptor PAR-1 is responsible for cellular effects of thrombin. PAR-1 plays an important role in the progression of different solid tumours in vitro. In breast cancer the level of PAR-1 expression correlates with invasiveness. Our aim was to correlate PAR-1 mRNA and protein expression level with the grade of differentiation of pancreatic tissue and cancer cell lines. PAR-1 protein was not detectable in the epithelium of healthy pancreas. Analysis of PAR-1 protein expression by immunofluorescence staining of pancreatic cancer cell lines revealed a correlation to the grade of differentiation. Quantitative analysis of PAR-1 protein expression by Western Blot analysis confirmed these observations. Analysis of PAR-1 mRNA expression showed low levels in healthy pancreas compared to pancreatic cancer tissue and the pancreatic cancer cell line MIA PaCa-2. The level of PAR-1 mRNA differed up to 25 fold between the respective pancreatic cancer cell lines. The eminent differences in PAR-1 expression, both protein and mRNA, between healthy pancreatic tissue and pancreatic cancer in vivo and in vitro emphasise the putative role of PAR-1 in pancreatic cancer progression.