Abstract
PURPOSE: The ubiquitin C-terminal hydrolase L1 (UCH-L1) belongs to the family of deubiquitinating enzymes. It is overexpressed in various tumour entities and associated with metastases formation in some solid tumours. However, only limited information about its role in breast cancer is available. The aim of this study was to examine the UCH-L1 expression in primary breast cancer and to determine its relevance as a potential prognostic marker. METHODS: We investigated both UCH-L1 mRNA expression in microarray data from 182 primary mammary carcinomas and UCH-L1 protein expression using a tissue microarray containing samples from 1,622 breast cancer patients. RESULTS: With both methods, high UCH-L1 expression correlated significantly with negative oestrogen receptor and progesterone receptor status and advanced tumour stage. Moreover by Kaplan-Meier analysis, high UCH-L1 mRNA and protein expression correlated with a significantly shorter overall survival. CONCLUSION: The data of our study suggest that high levels of UCH-L1 expression indicate a more aggressive tumour behaviour and might represent a potential target in breast cancer treatment.