ErbB receptor tyrosine kinase family expression levels in urothelial bladder carcinoma.

ErbB receptor tyrosine kinases family plays an important role in cell cycle regulation. Overexpression of ErbB receptors has been described in several solid tumors. The aim of this study was to investigate the levels of ErbB1, ErbB2, ErbB3, and ErbB4 expression in bladder cancer. Urinary bladder tumor samples were obtained from 33 bladder cancers and 7 non-cancerous bladder biopsies. The levels of ErbB1, ErbB2, ErbB3, and ErbB4 genes expression in bladder cancer were determined by real-time PCR. The presence of protein was confirmed by immunostaining. Expression of ErbB1, ErbB2, ErbB3, and ErbB4 genes increased 0.67, 4.72, 2.89, and 2.65-fold, respectively, in bladder tumors as compared with normal tissue. There was a significant difference between immunostaining results of ErbB4 protein in bladder tumors and normal bladder tissue (P<0.01). The present data suggest that ErbB2, ErbB3, and ErbB4 genes may have a role in bladder cancer tumorigenesis.