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).

Abstract

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.

• Authors: Joongho Shin, Ziqian Yuan, Kenneth Fordyce, Prashanth Sreeramoju, Tara S Kent, John Kim, Victor Wang, David Schneyer, Thomas K Weber
• Journal: Surgery (Surgery) Vol. 142 Issue 2 Pg. 222-7 (Aug 2007) ISSN: 0039-6060 [Print] United States
• PMID: 17689689 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

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

Topics

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