Expression of p53 family genes in urinary bladder cancer: correlation with disease aggressiveness and recurrence

Tumour Biol. 2014 Mar;35(3):2481-9. doi: 10.1007/s13277-013-1328-4. Epub 2013 Nov 11.

Abstract

p53 is a tumour suppressor gene with an established role in the majority of human neoplasias. Its homologues-p63 and p73-cannot be classified as tumour suppressors, since they encode isoforms with oncogenic properties as well. p63 plays a crucial role in epithelial cell differentiation and p73 is essential for neuronal cell development. The p63 and p73 expressions have been investigated in a variety of human tumours including bladder carcinomas; yet, this is the first study to simultaneously analyse the transcriptional levels of all p53 family members in bladder cancer. Using quantitative real-time polymerase chain reaction, we measured the mRNA expression of p53, p63 and p73 in 30 bladder tumours, each paired with adjacent normal tissue. All three studied genes were up-regulated in malignant specimens, p53 by 1.9-fold, p63 by threefold and p73 by twofold, respectively. Further analysis suggested that p63 and p73 act independently of p53 in the malignant bladder epithelium. Statistical analysis revealed that p63 overexpression was more frequent in recurrent bladder tumours (p = 0.045) and in older patients (p = 0.022). Papillary tumours also exhibited abnormal p63 expression (p = 0.026). Finally, p73 was up-regulated in Grade III one-site tumours (p = 0.040). Our results indicate that all p53 family members are abnormally expressed in bladder cancer but do not act synergistically. High levels of p63 correlate with non-muscle invasive tumours with frequent relapses, whereas p73 overexpression is associated with a more aggressive tumour phenotype.

MeSH terms

  • Aged
  • DNA-Binding Proteins / analysis
  • DNA-Binding Proteins / biosynthesis*
  • DNA-Binding Proteins / genetics
  • Female
  • Humans
  • Male
  • Membrane Proteins / analysis
  • Membrane Proteins / biosynthesis*
  • Membrane Proteins / genetics
  • Neoplasm Recurrence, Local / genetics*
  • Neoplasm Recurrence, Local / metabolism
  • Neoplasm Recurrence, Local / pathology
  • Nuclear Proteins / analysis
  • Nuclear Proteins / biosynthesis*
  • Nuclear Proteins / genetics
  • Protein Isoforms / genetics
  • RNA, Messenger / analysis
  • Real-Time Polymerase Chain Reaction
  • Tumor Protein p73
  • Tumor Suppressor Protein p53 / analysis
  • Tumor Suppressor Protein p53 / biosynthesis*
  • Tumor Suppressor Protein p53 / genetics
  • Tumor Suppressor Proteins / analysis
  • Tumor Suppressor Proteins / biosynthesis*
  • Tumor Suppressor Proteins / genetics
  • Urinary Bladder Neoplasms / genetics*
  • Urinary Bladder Neoplasms / metabolism
  • Urinary Bladder Neoplasms / pathology

Substances

  • CKAP4 protein, human
  • DNA-Binding Proteins
  • Membrane Proteins
  • Nuclear Proteins
  • Protein Isoforms
  • RNA, Messenger
  • TP53 protein, human
  • TP73 protein, human
  • Tumor Protein p73
  • Tumor Suppressor Protein p53
  • Tumor Suppressor Proteins