Altered expression patterns of lncRNA MEG3 and LINC01611 in patients with colorectal cancer

Colorectal cancer (CRC) is a major global health challenge, with long non-coding RNAs (lncRNAs) gaining attention as potential diagnostic biomarkers. This study aimed to experimentally validate bioinformatics findings on the expression patterns of maternally expressed gene 3 (MEG3) and LINC01611 in CRC patients from a specific ethnic population while considering associated risk factors. This in vitro study initially recruited 50 patients from a single ethnic group, with 48 completing the analysis after the exclusion of two samples. Two lncRNAs, MEG3 and LINC01611, were selected using Gene Expression Omnibus (GEO) microarray data and identified via R/BioConductor. Paired tissue samples (tumor and adjacent margins) were collected during surgery, and RNAs were extracted. Demographic and clinical data of patients were recorded, and gene expression was analyzed using quantitative real-time PCR (qPCR), with GAPDH as the internal control. Data analysis was performed using GraphPad Prism and SPSS software, with the significance level set at P < 0.05. The mean age of the patients was 59.5 ± 3.53 years, with 58.3 % (n = 28) being male, and 37.5 % of the patients had a history of smoking. The majority of patients had poorly differentiated (41.7 %) and stage II tumor (43.8 %), with lymph node metastasis commonly observed (60.4 %). The Wilcoxon signed-rank test revealed significant downregulation of MEG3 (32.396 fold change)and LINC01611(38.923 fold change) in tumor tissues compared to adjacent margins. A family history of CRC was associated with higher expression levels of MEG3 (1.48-fold, P = 0.038) and LINC01611 (1.03-fold, P = 0.007) in both tumor and margin tissues. Multivariable regression analysis demonstrated that lncRNAs had a significant association with tumor differentiation (P < 0.05), while other variables showed no statistically significant association (P > 0.05). Also, positive correlations were observed between MEG3 and LINC01611 expression levels in tumor (r = 0.649, P < 0.001) and margin (r = 0.424, P = 0.003) tissues. The significant downregulation of MEG3 and LINC01611 in tumor tissues compared to adjacent margin tissues highlights their potential role as tumor suppressors in CRC. These findings support further investigation into these lncRNAs as diagnostic biomarkers.