RT-PCR Analysis of ED-A,ED-B, and IIICS Fibronectin Domains: A New Screening Marker For Bladder Cancer

Abstract

Background: Fibronectin seems to play a very important role in the progression and invasion of bladder cancer. EDA, EDB, and IIICS domains of fibronectin are not expressed in the adult persons but they’re expressed in different cancers. The aim of this study is to investigate the mRNA of fibronectin in transitional carcinoma cells (TCC) of bladder to study these domains. Methods: A total of 20 patients with known bladder cancer were studied. Two of them excluded since their excised tissues were not enough for both the pathological examination and RNA study. Another 20 (control group) were normal volunteers who needed bladder operations. The excised tissue was immediately transferred to RNAlater (Ambion,TX). RNA was extracted via RNAWIZ (Ambion, TX). cDNA was made via RevertAid First Strand cDNA Synthesis Kit (Fermentas). PCR of the cDNAs was performed using primers for EDA, EDB, and IIICS (Eurogentec,Belgium). Results: For the first time, we present the expression of the oncofetal fibronectin mRNA in the transitional cell carcinoma of bladder. The high grade muscle invasive (G3T2) tumor, expressed ED-A, ED-B, and IIICS. Expression of ED-A, ED-B, and IIICS was confirmed in the two patients with G3T1 TCC. The four patients with G2Ta and G3Ta expressed both ED-A and ED-B. The four patients with G1T1 tumor expressed ED-A only, similar to the nine patients with G1Ta tumor. None of the normal volunteers expressed the oncofetal extra domains. The sensitivity of ED-A positive fibronectin RNA for detecting TCC of any kind is 100%, and of ED-B was only 35%. The specificity of ED-B positive fibronectin RNA for the high grade TCC is 100%. Conclusion: ED-A, ED-B, and IIICS could be used as useful markers for the diagnosis and following up of bladder carcinoma.
Keywords: Transitional Cell Carcinoma, bladder cancer, fibronectin, RT-PCR, oncofetal.