The circular RNA CDR1as regulate cell proliferation via TMED2 and TMED10

Abstract

Background: Circular RNAs (CircRNAs) are biologically active RNAs. CDR1as is one such circRNA previously reported to be a microRNA-7 (miR-7) sponge, thereby regulating associated gene expression. The specific underlying molecular mechanisms of CDR1as biology, however, remain largely unknown. Methods: We performed CDR1as knockdown in order to explore its function in cell proliferation, migration, the cell cycle, and tumorigenesis. We further employed quantitative proteomic analyses and associated bioinformatics strategies to globally assess CDR1as-regulated proteins (CRPs). Western blotting and immunofluorescence staining were used to validate the proteomic results. We additionally investigated a specific link between TMED2, TMED10, and miR-7 via a dual-luciferase reporter system, and generated CDR1as knockout cell lines via CRISPR/Cas9 editing. Results: We identified 353 proteins dysregulated upon CDR1as knockdown in 293 T cells. These CRPs were found to interact with one another and to play key roles in certain cellular pathways. Two such proteins, TMED2 and TMED10, were found to specifically contribute to the influence of CDR1as on cell proliferation. CDR1as may regulate these two TMED proteins through miR-7 sponging. We were able to further confirm these results using both CRISPRi cell lines and nude mouse models. Conclusion: This study suggested that CDR1as may regulate cell proliferation via serving as a miR-7 sponge, thereby regulating TMED2 and TMED10 expression. These results are an invaluable template for future streamlined studies of circRNAs.

Targeting circular RNAs as a therapeutic approach: current strategies and challenges

“…CDR1as knockout led to the dysregulation of 353 proteins, many of which were found to interact with each other and play critical roles in cellular pathways. 162 CDR1as locus has also been removed using CRISPR/Cas9 in vivo. 163 Prior to this deletion, it was verified that the antisense strand to CDR1as does not undergo transcription.…”

Circular RNA circYPEL2: A Novel Biomarker in Cervical Cancer

“…Notably, we observed 65.6% highly expressed circRNAs derived from lowly expressed host genes in CC ( Figure 1 H, red points). To verify the RNA-seq results, qPCR for these circRNAs were conducted in HeLa and SiHa cells, with 293T cell line, which is a widely used normal control according to previous works [ 26 , 27 , 28 , 29 ]. Results showed the expression of circYPEL2 was highest in seven circRNAs, which were consistent to RNA-seq results (Fold-change > 6, and adjusted p -value = 0.0090, Student unpaired t -test) ( Figure 1 I and Supplementary Figure S1D ).…”

The Emerging Picture of the Roles of CircRNA-CDR1as in Cancer

“…CDR1as is upregulated in numerous cancers, where it can sponge miR-7 and stimulate the expression of the downstream targeted genes, such as E2F3, EGFR, IGF-1R, CCNE1, PIK3CD, RAF1, PTEN, and KLF4. Accordingly, CDR1as was found to promote tumor proliferation in nasopharyngeal carcinoma, colorectal cancer, non-small-cell lung cancer, osteosarcoma, laryngeal squamous cell carcinoma, gastric cancer and esophageal squamous cell carcinoma, respectively (Tang et al, 2017;Li R. C. et al, 2018;Pan et al, 2018;Xu et al, 2018;Zhang J. et al, 2018;Zhang X. et al, 2018;Huang et al, 2019;Zhong et al, 2019;Yang et al, 2020). These studies demonstrated CDR1as-miR-641 Jiang et al, 2018;Li D. et al, 2020 Gastric cancer Upregulated Proliferation Migration Chemoresistance…”

“…As CDR1as can regulate the activity of miR-7 by sponging it, CDR1as exerts a wide range of physiological and pathological effects (Li et al, 2018b). Accordingly, CDR1as plays an important role in cellular proliferation and differentiation as well as cancer invasion and metastasis (Yan et al, 2018;Li L. et al, 2019;Wang et al, 2019;Yang L. et al, 2019;Zhou et al, 2019;Zou et al, 2019;Chen et al, 2020;Hanniford et al, 2020;Yang et al, 2020;Zhao F. et al, 2020).…”