LKB1 mutations and their correlation with LKB1 and Rheb expression in bladder cancer

Mol Carcinog. 2013 Aug;52(8):660-5. doi: 10.1002/mc.21902. Epub 2012 Mar 27.

Abstract

Although there are extensive studies on the genetics of bladder cancer, several questions remain unanswered. One of the pathways which are altered in bladder cancer is the mTOR signaling pathway. In the present study, we analyzed the expression of Rheb gene and genetic alterations in the LKB1 gene which are the key components of mTOR pathway. Nine exons of the LKB1 gene were analyzed by direct sequencing in 51 bladder cancer patients. To investigate the expression of Rheb and LKB1, real-time quantitative RT-PCR was performed in bladder tumor and normal bladder tissue samples. We did not observed a statistically significant difference in Rheb or LKB1 expression between the tumor and normal tissue samples. We detected a novel missense mutation creating stop codon in a high percent of the tumor samples. Five different single nucleotide substitutions were also observed in the introns. Our results indicate that LKB1 gene may play a role in the progression of bladder cancer.

Keywords: LKB1; Rheb; bladder cancer; mTOR pathway; mutation.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • AMP-Activated Protein Kinase Kinases
  • Base Sequence
  • Codon
  • Disease Progression
  • Exons
  • Gene Expression Regulation, Neoplastic*
  • Genotype
  • Humans
  • Introns
  • Monomeric GTP-Binding Proteins / genetics*
  • Neuropeptides / genetics*
  • Protein Serine-Threonine Kinases / genetics*
  • RNA, Messenger / genetics
  • Ras Homolog Enriched in Brain Protein
  • Urinary Bladder Neoplasms / genetics*
  • Urinary Bladder Neoplasms / pathology

Substances

  • Codon
  • Neuropeptides
  • RHEB protein, human
  • RNA, Messenger
  • Ras Homolog Enriched in Brain Protein
  • Protein Serine-Threonine Kinases
  • STK11 protein, human
  • AMP-Activated Protein Kinase Kinases
  • Monomeric GTP-Binding Proteins