Expression of the Bcl-2 family genes and complexes involved in the mitochondrial transport in prostate cancer cells

Int J Oncol. 2014 Oct;45(4):1489-96. doi: 10.3892/ijo.2014.2576.

Abstract

Alteration of molecular pathways triggering apoptosis gives raise to various pathological tissue processes, such as tumorigenesis. The mitochondrial pathway is regulated by both the genes of the Bcl-2 family and the genes encoding mitochondrial transport molecules. Those proteins allow a release of cyctochrome c through the outer mitochondrial membrane. This release activates the caspase cascade resulting in death of cells. There are at least two main transport systems associated with the family of Bcl-2 proteins that are involved in transport of molecules through the outer mitochondrial membrane, i.e., the voltage dependent anion channels (VDACs) and translocases of the outer mitochondrial membrane proteins (TOMs). We investigated the expression of genes of the Bcl-2 family, i.e., pro-apoptotic Bak and Bid, and anti-apoptotic Bcl-2; VDAC gene, i.e., VDAC1, VDAC2 and VDAC3; and TOMM genes, i.e., TOMM20, TOMM22 and TOMM40. This study was performed at the mRNA and the protein level. Fourteen paraffin embedded prostate cancer tissues and five normal prostate tissues were analyzed by the quantitative PCR array and immunohistochemistry. We found a significant increase in both mRNA expression of the anti-apoptotic Bcl-2 gene and VDAC1 gene in prostate cancer tissue in comparison with their normal counterparts. Translation of the anti-apoptotic Bcl-2 and VDAC1 genes in prostate cancer tissue was slightly increased. We observed no significant differences in the mRNA expression of the pro-apoptotic Bak and Bid genes, VDAC2 or VDAC3 genes or the three TOMM genes in these tissues. The pro-apoptotic Bax protein was downtranslated significantly in secretory cells of prostate cancer as compared to normal prostate. We suggest that this protein is a good candidate as biomarker for prostate cancer.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Gene Expression Regulation, Neoplastic
  • Humans
  • Male
  • Membrane Transport Proteins / genetics
  • Membrane Transport Proteins / metabolism
  • Mitochondria / metabolism
  • Mitochondrial Membranes / metabolism
  • Prostatic Neoplasms / genetics*
  • Prostatic Neoplasms / metabolism
  • Prostatic Neoplasms / pathology
  • Proto-Oncogene Proteins c-bcl-2 / genetics*
  • Proto-Oncogene Proteins c-bcl-2 / metabolism
  • Signal Transduction
  • Voltage-Dependent Anion Channels / genetics*
  • Voltage-Dependent Anion Channels / metabolism
  • Young Adult
  • bcl-2-Associated X Protein / genetics*
  • bcl-2-Associated X Protein / metabolism*

Substances

  • BAX protein, human
  • Membrane Transport Proteins
  • Proto-Oncogene Proteins c-bcl-2
  • Voltage-Dependent Anion Channels
  • bcl-2-Associated X Protein