Published online Apr 16, 2022. doi: 10.12998/wjcc.v10.i11.3352
Peer-review started: October 29, 2021
First decision: December 27, 2021
Revised: December 30, 2021
Accepted: February 12, 2022
Article in press: February 12, 2022
Published online: April 16, 2022
Processing time: 161 Days and 5.7 Hours
Colorectal cancer (CRC) is a common tumor worldwide. Circular ribonucleic acids (circRNAs) have been reported to regulate CRC as microRNA (miRNA) sponges. However, the aberrant expression and biological functions of circRNAs in CRC remain to be further explored.
CircRNAs might serve as novel biomarker candidates for CRC diagnosis. Further exploration of useful biomarkers to improve CRC diagnosis and treatment is crucial.
This study aimed to identify circRNAs that could be potential biomarkers of CRC and explore their functions in CRC carcinogenesis.
Cir_0000375 and circ_0011536 were selected as CRC biomarker candidates using the Gene Expression Omnibus (GEO) database. Quantitative real-time polymerase chain reaction was utilized to evaluate the expression levels of these 2 circRNAs in CRC tissues, serum samples and cell lines. Functional experiments, including cell counting kit-8 (CCK-8), wound healing and Transwell invasion assays, were carried out after overexpression of cir_0000375 and circ_0011536 in CRC cell lines. Furthermore, the expression levels of target miRNAs in CRC tissues were explored in GEO datasets and CRC cell lines. Then, the interactions of circRNAs and miRNAs and enrichment analysis of the miRNAs and target genes were further performed.
Our findings demonstrated that circ_0000375 and circ_0011536 were downregulated in CRC cell lines, tissues and serum samples and showed good diagnostic performance. Furthermore, these 2 circRNAs significantly inhibited CRC cell proliferation, migration and invasion. As potential targets of circ_0000375 and circ_0011536, miR-1182 and miR-1246, respectively, were overexpressed in CRC cells and tissues.
Circ_0000375 and circ_0011536 may function as tumor suppressors and serve as novel biomarkers for CRC diagnosis and are promising candidates for therapeutic exploration.
Our findings uncover the mechanisms by which 2 circRNAs, circ_0000375 and circ_0011536, suppress CRC cell growth and progression and provide novel diagnostic biomarkers and promising therapeutic targets for CRC.