OBJECTIVES: The development of colorectal cancer (CRC) is characterized by 
multiple genetic alterations. Transcribed ultraconserved regions (T-UCRs) are a 
subset of 481 sequences longer than 200 bp, which are absolutely conserved 
between orthologous regions of human, rat and mouse genomes, and are actively 
transcribed. It has recently been proven in cancer systems that differentially 
expressed T-UCRs could alter the functional characteristics of malignant cells. 
Genome-wide profiling revealed that T-UCRs have distinct signatures in human 
leukemia and carcinoma.
METHODS: In our study, we examined the expression levels of uc.43, uc.73, 
uc.134, uc.230, uc.339, uc.388 and uc.399 in 54 samples of primary colorectal 
carcinomas and 15 samples of non-tumoral adjacent tissues by real-time PCR. 
T-UCR expression levels were also correlated with commonly used 
clinicopathological features of CRC.
RESULTS: Expression levels of uc.73 (p = 0.0139) and uc.388 (p = 0.0325) were 
significantly decreased in CRC tissue, and uc.73 indicated a positive 
correlation with overall survival (p = 0.0315). The lower expression of uc.388 
was associated with the distal location of CRC (p = 0.0183), but no correlation 
of any evaluated T-UCR with clinical stage, grade and tumor diameter was 
observed.
CONCLUSION: Our preliminary results suggest that uc.73 and uc.388 could be 
potential diagnostic and prognostic biomarkers in CRC patients.