Identification of Two Novel Circular RNAs Deriving from BCL2L12 and Investigation of Their Potential Value as a Molecular Signature in Colorectal Cancer

• Published in: International journal of molecular sciences 2020-11, Vol.21 (22), p.8867
• Main Authors: Karousi, Paraskevi, Artemaki, Pinelopi I, Sotiropoulou, Christina D, Christodoulou, Spyridon, Scorilas, Andreas, Kontos, Christos K
• Format: Article
• Language: English
• Subjects: Adult; Aged; Aged, 80 and over; alternative splicing; Apoptosis; Binding sites; Biomarkers; Biomarkers, Tumor - blood; circRNAs; Colorectal cancer; Colorectal carcinoma; Colorectal Neoplasms - blood; Colorectal Neoplasms - genetics; Colorectal Neoplasms - pathology; Computational Biology; Deoxyribonucleic acid; DNA; DNA methylation; DNA repair; Female; Gene Expression Regulation, Neoplastic - genetics; Genes; Humans; Male; MicroRNAs; MicroRNAs - blood; Middle Aged; miRNA; miRNA sponges; Muscle Proteins - blood; Muscle Proteins - genetics; Proteins; Proto-Oncogene Proteins c-bcl-2 - blood; Proto-Oncogene Proteins c-bcl-2 - genetics; RNA, Circular - blood; RNA, Circular - genetics; RNA-binding protein; RNA-binding proteins; RNA-Binding Proteins - blood; RNA-Binding Proteins - genetics; Subgroups; transcriptomics; Tumors
• ISSN: 1422-0067; 1661-6596; 1422-0067
• DOI: 10.3390/ijms21228867

The utility of circular RNAs (circRNAs) as molecular biomarkers has recently emerged. However, only a handful of them have already been studied in colorectal cancer (CRC). The purpose of this study was to identify new circRNAs deriving from , a member of the BCL2 apoptosis-related family, and investigate their potential as biomarkers in CRC. Total RNA extracts from CRC cell lines and tissue samples were reversely transcribed. By combining PCR with divergent primers and nested PCR followed by Sanger sequencing, we were able to discover two circRNAs. Subsequently, bioinformatical tools were used to predict the interactions of these circRNAs with microRNAs (miRNAs) and RNA-binding proteins (RBPs). Following a PCR-based pre-amplification, real-time qPCR was carried out for the quantification of each circRNA in CRC samples and cell lines. Biostatistical analysis was used to assess their potential prognostic value in CRC. Both novel circRNAs likely interact with particular miRNAs and RBPs. Interestingly, circ-BCL2L12-2 expression is inversely associated with TNM stage, while circ-BCL2L12-1 overexpression is associated with shorter overall survival in CRC, particularly among TNM stage II patients. Overall, we identified two novel circRNAs, one of which can further stratify TNM stage II patients into two subgroups with substantially distinct prognosis.