Cancer of the gastrointestinal tract, i.e. esophageal, gastric, and colorectal cancer, comprises one of the most common forms of cancer in the Western world, and is a prominent cause of cancer-related death. The vast majority of GI cancer patients die as the result of the formation of distant tumor metastases. One of the main goals of our research is to acquire a better understanding of the molecular basis of colorectal tumor invasion and metastasis. Tumor cells largely depend on the surrounding stroma to establish a permissive and supportive growth environment, and to acquire metastatic potential. They adapt their microenvironment by recruiting endothelial, inflammatory, and fibroblast-like cells. In turn, the newly formed stromal compartment strongly affects tumor cell behaviour by producing growth factors, chemokines, hormones and extracellular matrix components. In fact, one could even postulate that epithelial tumor growth is impossible without the support of the stromal compartment. Therefore, one of our main research focus points will be to gain a better understanding of the interactions between tumor cells and the stromal tissue. In the last decade it has also become clear that chronic inflammation strongly contributes to the formation and progression of various forms of cancer, including those of the gastrointestinal tract. Patients suffering from chronic forms of inflammatory bowel disease show an increased risk of tumor formation, while reflux-induced chronic inflammation is thought to be the initiating factor for the development of Barrett's esophagus, a precursor of adenocarcinoma of the gastro-esophageal junction. We will establish new research lines aimed at obtaining a better understanding of inflammation-inducing factors in the gastrointestinal tract, as well as investigate immunological aspects of colorectal cancer-related neoplastic progression.