Differences in T cell immune-related lncRNA and mRNA expression patterns between right- and left-sided colorectal cancers

Abstract

Background: Right-sided colorectal cancer (RCRC) and left-sided colorectal cancer (LCRC) harbor different genetic alterations associated with immune response.

Objective: This study aimed to analyze the differences in T cell immune-related RNA expression patterns between RCRC and LCRC.

Methods: The differentially expressed genes (DEGs) and lncRNAs (DElncRNAs) between LCRC and RCRC were screened from the Cancer Genome Atlas (TCGA) database. A correlation analysis between DEGs or DElncRNAs and differential T cells was also performed to obtain T cell-related genes, followed by miRNA prediction. The mRNA-lncRNA network and the competitive endogenous RNA (ceRNA) network were subsequently constructed, and the expression level of mRNA in the ceRNA network was verified using GSE104645.

Results: RCRC patients had a poorer prognosis and were older than LCRC patients. In total, 923 DEGs and 328 DElncRNAs were screened between LCRC and RCRC patients. Compared to RCRC patients, LCRC patients showed a decrease in CD8⁺ T cells. In addition, 26 miRNAs, 8 mRNAs, and 10 lncRNAs were included in the ceRNA network. Finally, the validation analysis revealed that CDHR1 and PRLR were significantly downregulated, while TRIB2 was upregulated in RCRC patients compared to LCRC patients.

Conclusion: The analysis of T cell immune-related RNA expression might provide new insights into the underlying molecular mechanisms of the differences between LCRC and RCRC.

Keywords: Immune cells; Left-sided CRC; LncRNA-mRNA network; Right-sided CRC.