Abstract: |
Target genes implicated in cellular transformation and tumor progression have been divided into two categories: proto-oncogenes which, when activated, become dominant events characterized by the gain of function, and tumor suppressor genes which become recessive events characterized by the loss of function. Alterations in proto-oncogenes and tumor suppressor genes seem equally prevalent among human cancers. Multiple mutations appear to be required to conform the malignant phenotype. Proto-oncogenes are activated mainly by point mutations; however, amplification and translocation events are also common. Tumor suppressor genes are inactivated by an allelic loss followed by a point mutation of the remaining allele. The prototype suppressor genes are the retinoblastoma (RB) gene and the TP53 (also known as p53) genes. Recent studies have shown that inactivation of TP53 and RB occur in bladder tumors that have a more aggressive clinical outcome and poor prognosis. We will review the molecular abnormalities associated with both oncogenes and tumor suppressor genes in bladder tumors, and also discuss the potential clinical use of their detection. The implementation of objective predictive assays to identify these alterations in clinical material will enhance our ability to assess tumor biological activities and to design effective treatment regimes. |
Keywords: |
immunohistochemistry; gene deletion; mutation; review; cancer growth; neoplasm staging; phenotype; proto oncogene; gene amplification; prevalence; tumor markers, biological; alleles; cytogenetics; bladder cancer; protein p53; urinary bladder neoplasms; cell transformation, neoplastic; oncogenes; chromosome aberration; tumor suppressor gene; gene expression regulation, neoplastic; disease progression; clinical protocols; forecasting; translocation, genetic; bladder neoplasms; chromosome aberrations; point mutation; tumor suppressor genes; transitional cell carcinoma; patient care planning; genes, tumor suppressor; genes, p53; biological tumor markers; proto-oncogenes; ras genes; genes, retinoblastoma; humans; prognosis; human; priority journal; p53 genes
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