Project description:We aim to identify profiling of circRNAs in renal biopsies from lupus nephritis (LN) patients. In this study, seven frozen renal biopsies from patients with LN class IV were used for circRNA profiling by second generation of RNA sequencing. Three kidney tissue 5 cm far from renal tumors were used as normal control .

2020-12-16 | GSE108340 | GEO

human circRNA binding proteins in neuroblastoma

Project description:Circular RNAs (circRNAs), a noncoding RNA class originating from alternative splicing, are highly abundant in neural tissues and were shown to regulate gene expression e.g. by interacting with microRNAs and RNA-binding proteins. Neuroblastoma is an embryonal neoplasia, which arises from undifferentiated neural crest cells. Here, we aimed to explore, whether circRNAs influence the pathogenesis of high-risk neuroblastoma. We performed whole-transcriptome sequencing of 104 primary neuroblastoma samples of all risk-groups and identified 5,203 unique circRNAs involving 2,302 genes. Candidate circRNA expression did not correlate with host gene expression, indicating independent regulatory mechanisms. circRNAs were significantly downregulated in the MYCN-amplified high-risk tumors. These findings were independently reproduced in a tetracycline-inducible MYCN-overexpression system based on a non MYCN-amplified neuroblastoma cell line, suggesting that MYCN drives this global circRNA repression. We identified the RNA helicase DHX9 as a mediator of this global suppressive effect of MYCN on circRNAs. Comparing our RNA sequencing data with other cancers and controls revealed a circRNA subset specifically upregulated in neuroblastoma that included a circRNA derived from the ARID1A tumor suppressor gene. Specific circARID1A knockdown resulted in reduced proliferation, cell numbers and viability, prompted apoptosis and induced a differentiated phenotype. Neither knockdown, nor overexpression of circARID1A influenced ARID1A mRNA and protein levels significantly. To dissect the potential mode of function, we performed a pulldown assay with subsequent mass spectrometry. We identified the RNA-binding protein KHSRP as an interaction partner that participates in the mechanism of action of circARID1A. In summary, this study highlights an important role of circRNAs in neuroblastoma biology and may establish this RNA class as a future therapeutic target and biomarker.

2023-04-06 | PXD026053 | Pride

Human circRNA expression profiling in plasma sample of hepatocellular carcinoma

Project description:Arraystar Human circRNA Microarray is designed for the global profiling of human circRNAs. In this study, we applied a circRNA microarray to screen the potential biomarker for HCC. 20 samples extracted from plasma samples including HCC group before operation, and after operation, CH group and control group. Each group contained five samples.

2021-03-02 | E-MTAB-8799 | biostudies-arrayexpress

Immunopeptidomics-based identification of naturally presented non-canonical circRNA-derived peptides

Project description:Circular RNAs (circRNAs) are covalently closed non-coding RNAs lacking the 5’ cap and the poly-A tail. Nevertheless, it has been demonstrated that certain circRNAs can undergo active translation. Therefore, aberrantly expressed circRNAs in human cancers could be an unexplored source of tumor-specific antigens, potentially mediating anti-tumor T cell responses. This study presents an immunopeptidomics workflow with a specific focus on generating a circRNA-specific protein fasta reference. The main goal of this workflow is to streamline the process of identifying and validating human leukocyte antigen (HLA) bound peptides potentially originating from circRNAs. We increased the analytical stringency of our workflow by retaining peptides identified independently by two mass spectrometry search engines and/or by applying a group-specific FDR for canonical-derived and circRNA-derived peptides. A subset of circRNA-derived peptides specifically encoded by the region spanning the back-splice junction (BSJ) were validated with targeted MS, and with direct Sanger sequencing of the respective source transcripts. Our workflow identified 54 unique BSJ-spanning circRNA-derived peptides in the immunopeptidome of melanoma and lung cancer samples. Our novel approach enlarges the catalog of source proteins that can be explored for immunotherapy.

2024-03-20 | PXD043989 | Pride

circRNA-sequencing of blood plasma exosomes from cutaneous squamous cell carcinoma patients

Project description:circRNA sequencing for 6 samples

2019-08-22 | GSE136113 | GEO