A del T poly T (8) mutation in the 3' untranslated region (UTR) of the CDK2-AP1 gene is functionally significant causing decreased mRNA stability resulting in decreased CDK2-AP1 expression in human microsatellite unstable (MSI) colorectal cancer (CRC)

Surgery. 2007 Aug;142(2):222-7. doi: 10.1016/j.surg.2007.04.002.


Background: We have previously published results indicating that decreased expression of CDK2-AP1 in MSI human colorectal cancer is associated with deletion mutations in the poly (T) 8 repeat sequence within the 3'-UTR of the CDK2-AP1 gene. In this study, we test the hypothesis that the del T mutation results in decreased CDK2-AP1 expression by causing reduced mRNA stability.

Methods: We introduced wild-type and mutant 3'-UTR sequences fused to a green fluorescent protein (GFP) gene separately into human CRC cell lines and quantified the expression of the GFP gene. Native CDK2-AP1 mRNA stability was measured in human CRC cell lines, using an actinomycin D assay and the mRNA structure folding software mfold 3.2.

Results: Mutant GFP-3'-UTR samples demonstrated significantly reduced GFP expression compared with wild-type GFP-3'-UTR as measured by both FACS and real-time PCR. Both the actinomycin D assay and mfold software demonstrated significantly reduced mRNA stability for the del T poly (T) 8 transcript compared with the wild type.

Conclusions: In summary, these novel results support our hypotheses that the del T poly (T) 8 observed in the 3'-UTR of the CDK2-AP1 gene in human MSI CRC is functionally significant and results in decreased CDK2-AP1 expression. The results also indicate the mechanism of this decreased expression is caused at least in part by decreased mRNA stability.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • 3' Untranslated Regions / genetics
  • Cell Line, Tumor
  • Colorectal Neoplasms / genetics*
  • Colorectal Neoplasms / physiopathology
  • Gene Deletion*
  • Gene Expression Regulation, Neoplastic
  • Green Fluorescent Proteins / genetics
  • Humans
  • Microsatellite Instability
  • Nucleic Acid Conformation
  • RNA Stability / genetics*
  • RNA, Messenger / chemistry
  • RNA, Messenger / genetics
  • RNA, Neoplasm / chemistry
  • RNA, Neoplasm / genetics
  • Tumor Suppressor Proteins / genetics*


  • 3' Untranslated Regions
  • CDK2AP1 protein, human
  • RNA, Messenger
  • RNA, Neoplasm
  • Tumor Suppressor Proteins
  • Green Fluorescent Proteins