Background: Long noncoding RNAs (lncRNAs) have recently been recognized as a new layer of biological regulation. They participate in mRNA regulation and may be useful as prognostic factors and drug targets. Colorectal cancer (CRC) is a common tumor that is characterized by its high mortality rate. Despite improvements in screening of CRC, the prognosis is still poor. Therefore, there is an urgent need to develop effective biomarkers for the detection of CRC. This study was designed to measure the expression of several oncogenic lncRNAs, including PANDAR, MALAT1, PCAT6, CCAT1, UCA1, MEG3, CCAT2, and BCAR4, in blood samples of healthy individuals and CRC patients. Methods: Total RNA was isolated from whole blood of 63 CRC patients and 40 controls and the expression of the lncRNAs was determined by real-time polymerase chain reaction and measured by REST2009 software. All p-values <0.05 were considered statistically significant. Results: The results showed that the expression levels of MALAT1, CCAT1, and PANDAR were significantly upregulated with 1.86, 4.54, and 4.68-fold higher levels (p < 0.05), respectively, in the blood of CRC patients compared to the controls. However, the other lncRNAs examined were not significantly expressed differentially in CRC blood samples. Conclusion: The findings of this study suggest that the expression of MALAT1, CCAT1, and PANDAR in blood could serve as potential biomarkers for CRC prognosis.
Keywords: Saudi patients; colorectal cancer; long noncoding RNAs; prognosis.