Expression profiling of angiogenic genes for the characterisation of colorectal carcinoma.

The developement of new blood and lymphatic vessels is a crucial event for cancer growth, metastases and relapse after therapy. In this work the expression levels of chemokines, angiogenic and angiostatic factors and their receptors were determined in paired mucosal and tuour samples of patients with colorectal carcinoma and correlated with clinical and histological parameters by advanced multifactorial analyses. The most important predictors to descriminate between tumour and paired normal mucosa turned out to be the levels of expression of plexin-A1 and stromal cell-derived factor (SDF-1), the former overexpressed and the latter downregulated in tumours. The levels of osteopontin and Tie-2 transcripts discriminated between the presence and absence of lymph node infiltration, the former oberexpressed in the presence of infiltration whilst the latter providing a protective role. These results add to the notion that the expression levels of selected genes involved in new blood and lymphatic vessel formation represent trustable biomarkers of tumor developement and invasion and contribute to identification of novel molecular classifiers for colorectal carcinoma.