stem cell self-renewal gene, Musashi 1, is highly expressed in tumor and non-tumor samples of human bladder.

CONTEXT: The stem cell model for cancer assumes that a key event in tumorigenesis is the deregulation of genes involved in the regulation of stem cell self-renewal. The Musashi family is an evolutionarily conserved group of neural RNA-binding proteins. In mammals, the family consists of two individual genes, Musashi 1 (MSI1) and MSI2, encoding the Musashi 1 and Musashi 2 proteins. Musashi 1 is involved in the regulation of self-renewal of stem cells. Recently, its over-expression has also been reported in a variety of human tumors. AIMS: To investigate a potential expression of the stem cell self-renewal gene, Musashi 1, in human bladder cancer, we examined its gene expression in a series of tumor and non-tumor tissue samples of bladder. MATERIALS AND METHODS: Relative expression of MSI1 was determined by the real-time quantitative reverse transcription polymerase chain reaction (qRT-PCR) in 70 surgical samples of bladder. RESULTS: Using specific primers for MSI1 and TBP (as an internal control) for qRT-PCR technique, we found a relatively high expression level of MSI1 in all examined tumor and non-tumor bladder tissue specimens. However, our data did not show any correlation between the level of gene expression and tumor/non-tumor states of the samples (P>0.05). CONCLUSIONS: All together, our data demonstrated that Musashi 1 is highly and un-differentially expressed in both examined tumoral and apparently normal bladder tissues.