Overexpression of the Interferon regulatory factor 4-binding protein in human colorectal cancer and its clinical significance

Cancer Epidemiol. 2009 Aug;33(2):130-6. doi: 10.1016/j.canep.2009.05.004. Epub 2009 Jul 10.

Abstract

Background: IFN regulatory factor 4-binding protein (IBP) is a novel type of activator of Rho GTPases. It has been linked with differentiation and apoptosis of lymphocytes, but its function in oncogenesis remains unclear. Here we studied the expression of endogenous IBP in four human colorectal cancer cell lines, normal, adenoma and tumor colorectal tissues.

Methods: Molecular (Western blot and RT-PCR), and confocal analyses were used to investigate IBP expression in human colorectal cancer cell lines. Matched normal and tumor tissue sections of 63 patients and 15 adenoma tissue sections were analyzed for IBP expression by immunohistochemistry (IHC).

Results: IBP was ubiquitely expressed in human colorectal cancer cell lines. The expression of IBP can be detected at both the mRNA and protein level in SW480, SW620 and HT29 cells. Clinically, IBP were elevated in human colorectal cancer specimens in comparison to normal colorectal tissues. Substantial high expression of IBP was observed in colorectal cancer tissues (67%), whereas corresponding normal tissues and 15 adenoma tissues showed consistently absent immunoreactivity of IBP. Moreover, IBP expression is correlated with the differentiation level of colorectal cancer cells (p<0.05) and clinical stage of patients (p<0.01).

Conclusions: Our data show, for the first time, a dysregulated expression of IBP in human colorectal cancer, offering new perspectives for its role in cancer development and progression. IBP may be a novel tumor marker and a therapeutic target for colorectal cancer.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adenocarcinoma / genetics
  • Adenocarcinoma / metabolism*
  • Adenocarcinoma / secondary
  • Adenocarcinoma, Mucinous / genetics
  • Adenocarcinoma, Mucinous / metabolism*
  • Adenocarcinoma, Mucinous / secondary
  • Adenocarcinoma, Papillary / genetics
  • Adenocarcinoma, Papillary / metabolism*
  • Adenocarcinoma, Papillary / secondary
  • Adenoma / genetics
  • Adenoma / metabolism*
  • Adenoma / pathology
  • Aged
  • Animals
  • Blotting, Western
  • Colon / metabolism
  • Colon / pathology
  • Colorectal Neoplasms / genetics
  • Colorectal Neoplasms / metabolism*
  • Colorectal Neoplasms / pathology
  • DNA-Binding Proteins / genetics
  • DNA-Binding Proteins / immunology
  • DNA-Binding Proteins / metabolism*
  • Enzyme-Linked Immunosorbent Assay
  • Female
  • Fluorescent Antibody Technique
  • Guanine Nucleotide Exchange Factors / genetics
  • Guanine Nucleotide Exchange Factors / immunology
  • Guanine Nucleotide Exchange Factors / metabolism*
  • Humans
  • Immunoenzyme Techniques
  • Male
  • Middle Aged
  • Nuclear Proteins / genetics
  • Nuclear Proteins / immunology
  • Nuclear Proteins / metabolism*
  • Prognosis
  • RNA, Messenger / genetics
  • RNA, Messenger / metabolism
  • Rabbits
  • Recombinant Proteins / genetics
  • Recombinant Proteins / immunology
  • Recombinant Proteins / metabolism
  • Rectum / metabolism
  • Rectum / pathology
  • Reverse Transcriptase Polymerase Chain Reaction
  • Tumor Cells, Cultured

Substances

  • DEF6 protein, human
  • DNA-Binding Proteins
  • Guanine Nucleotide Exchange Factors
  • Nuclear Proteins
  • RNA, Messenger
  • Recombinant Proteins