Background: Long non-coding RNA regulator of reprogramming (LINC-RoR) has shown different expressions in a variety of tumors as a stem cell inducer through reprogramming regulation. However, its role and regulation mechanisms in colorectal cancer (CRC) are still unclear.
Materials and Methods: Quantitative real-time PCR and Western blot were performed to examine LINC-RoR expression in paired CRC samples and cell lines. The relationship of LINC-RoR expression with clinicopathological characteristics and clinical outcomes was analyzed. The biological functions of LINC-RoR were studied by MTS and colony formation in vitro. Cell apoptosis was analysed by the flow cytometry. The Dual-luciferase reporter assays and RIP assays were performed to explore the regulatory relationship of LINC-RoR.
Results: In this study, we found that LINC-RoR was upregulated in CRC cell lines and tissues. High expression of LINC-RoR was associated with poorer survival time and multivariate analysis results showed that LINC-RoR was an independent risk factor of tumor malignancy progression. Overexpression of LINC-RoR promoted the cell proliferation and knocked down it can reverse the effect in vitro. The regulatory network of LINC-ROR/miR-6833-3p/SMC4 was predicted with bioinformatics analysis tools and validated via dual-luciferase reporter assays and RIP. Further study revealed that in overexpression LINC-RoR cell lines the expression of miR-6833-3p was downregulated and miR-6833-3p can inhibit its target gene SMC4, the apoptosis-related protein.
Conclusion: We concluded that LINC-RoR functions as an oncogene in CRC through the miR-6833-3p/SMC4 pathway.
Keywords: LINC-RoR, colorectal cancer, miR-6833-3p, SMC4, non-coding RNA, apoptosis