Hemmung von YB-1 als neuer therapeutischer Ansatz zur Verringerung der Expression von EGFR, HER-2 und IGF-IR beim Ösophaguskarzinom

The Y-box binding protein-1 (YB-1) is an oncogenic transcription factor that is highly expressed in many malignant tissues, including cancers of the breast and non-small cell lung cancer. Although these findings suggest an involvement of YB-1 in the progression of malignancies, so far no data as to its role in esophageal cancer (EC) are available. Molecular profiling studies have identified HER-2, Epidermal Growth Factor Receptor (EGFR) and Insulin-like-Growth-Factor I Receptor (IGF-IR) as co-factors in tumor progression. Inhibition of YB-1 leads to suppression of EGFR and HER-2 in breast cancer. Also, EGFR, IGF-IR and HER-2 are highly expressed in EC and associated with tumor growth and poor survival. The aim of this study was to evaluate the impact of YB-1 in EC and its influence on different protein tyrosine kinase receptor expression. For this, a tumor tissue microarray (TMA) was constructed from 293 primary esophageal carcinomas, 146 corresponding lymph nodes and 47 distant metastases. The TMA slides were analysed by immunhistochemistry for YB-1 expression.