Protein And MRNA Expression Of MDM2, P53 And Rb In Bladder TCC, Their Correlations, And Their Roles In Tumorigenesis And Prognosis

Bladder cancer is one of the most common diseases treated by urologists. The nosogenesis and prognosis of bladder tumor have been always the focus of study in the urology field. Oncogene MDM2 and tumor suppressor gene p53 and Rb are the known ones that have close correlation with the pathogenesis and prognosis of many kinds of cancers. Researchers allover the world have done lots of good study on them, but bladder cancer especially the TCC ' s accession need pass through complicated, multiple steps. We choose the gene MDM2,p53 and Rb as the objects to study their mRNA and protein expression in the TCC of bladder using the RT-PCR and ICH (immunohistochemistry) technology. The results are as the following:1. In keeping with bladder TCC' s stage and grade increasing the mRNA expression of the genes MDM2 and p53 is stepping up. however, the RJB' s changes have not the correlation with the malignancy. The MDM2 mRNA expression is associated with the other two genes. Thus, measuring MDM2/p53 mRNA expression using RT-PCR may be a simple, useful approach for predicting the prognosis of bladder TCC patients. These three genes' mRNA expression is controlled by an autoregulatory feedback loop.2. With the TCC' s malignancy increasing, the protein expression of p53 were augmented significantly, but the pRb protein were decreased. No statistical significance can be found between these two gene' s protein expression. This suggest that the co-expression of p53/RB protein is important in the tumorigenesis of bladder TCC. P53' s role is to induce the accession of this disease but RB just to prevent. mdm2 protein expression were decreased when the stages and grades increased. It has a negative correlation with p53 protein and a positive one with pRb.These facts suggest that MDM2, p53 and Rb gene harmonize in the tumorigenesis and progression of bladder TCC. Among them there are positive and negative autoregulatory feedback loop on the level of transcription and translation when the bladder TCC occurs.3. In the ICH experiments, we found about 84% of the cells that have the positive staining of p53 nucleoprotein are in the division phase, showing the nucleus shape is big and irregular. With the intensified malignancy degree of tumors, the proportion of this cells were increased. It is suggested that the reason why the protein and mRNA expression were higher in line with the stage is because the proportion of bad differentiated cells is augmented. Thus as a bridge p53 correlates the stage and grade systems of bladder TCC.