Functional role of small extrachromosomal circular DNA in colorectal cancer - PubMed
19 hours ago
- #colorectal cancer
- #gene expression
- #eccDNA
- Small extrachromosomal circular DNA (eccDNA) is more abundant in colorectal cancer tumors than in normal adjacent tissues, correlating with chromosomal amplifications.
- Whole intact genes found on 1.29% of eccDNA are nonrandom, with 84 genes recurring across patients; 19% of these are cancer-associated and often show increased expression.
- eccDNA-borne genes contribute more to gene expression than linear amplifications or larger ecDNA, exemplified by the cytokine CXCL5, which drives upregulation and immune cell recruitment.
- eccDNA forms preferentially at sites of open chromatin and active transcription, with boundaries marked by CTCF protein, and higher eccDNA levels correlate with poorer relapse-free survival in patients.