Expression of proto-oncogene c-Myc in patients with urinary bladder transitional cell carcinoma

Abstract. Background:. c-Myc is a proto-oncogene located on human chromosome 8. It encodes a transcriptional factor which regulates the expression of approximately 10% to 15% of human genes, playing a crucial role in cell growth, differentiation, cellular metabolism, apoptosis, and cell transformation. The aim of this study is to correlate the expression of c-Myc in patients suffering from urinary bladder transitional cell carcinoma with tumor grade, stage, and lymph node metastases. Materials and methods:. Formalin-fixed, paraffin-embedded tissue samples were obtained from 54 consecutive patients who underwent transurethral resection of bladder tumor or radical cystectomy (RC) as treatment for urinary bladder transitional cell carcinoma. Immunohistochemistry was performed using c-Myc monoclonal antibody and c-Myc expression was then analyzed for correlation with tumor stage, grade, and lymph node metastases. Results:. From a total of 54 patients, 42 (77.8%) had c-Myc positive staining and 12 (22.2%) were c-Myc negative. In the c-Myc positive group, 28 patients (66.7%) had low grade tumors and 33 (78.6%) presented with non-muscle-invasive disease (p