Specific protein and miRNA patterns characterise tumour-associated fibroblasts in bladder cancer.

PURPOSE: Tumour development and progression are strongly affected by interaction of tumour cells and tumour stroma. Different tumour models demonstrate a supportive effect of tumour-associated fibroblasts (TAF) on the tumour genesis. Aims of the present study are the isolation of TAF from primary urinary bladder tumour specimens and the proteomic and epigenetic characterisation.
METHODS: TAF were isolated from cultured urinary bladder tumour specimens. Therefore, primary tumour material was treated with EDTA followed by two separated detachment steps. Non-tumour fibroblasts were isolated from foreskin and normal bladder tissues. Proteins and total RNA were isolated from cultured fibroblasts. Protein pattern analyses were carried out by SELDI-TOF-MS. The miRNA expression profile was analysed by miRNA microarray.
RESULTS: By optimising cell culture routines, we achieved to isolate and subsequently cultivate TAF from primary tumour material of the urinary bladder. SELDI-TOF-MS measurements reveal distinct differences in the proteomic patterns of TAF and non-tumour fibroblasts. Microarray analyses indicate specific expression of several miRNAs in TAF and non-tumour fibroblasts.
CONCLUSION: In summary, we determined proteomic and epigenetic differences between non-tumour fibroblasts and TAF of urinary bladder carcinoma and identified specific protein expression patterns as well as miRNA profiles of TAF in comparison with non-tumour fibroblasts. These findings provide more insights into the complex tumour network and a good starting point for the identification of markers for the prediction of tumour development and progression based on specific TAF expression patterns.