Epigenetic reprogramming by promoter hypomethylation is linked to aberrant gene expression and transcriptomic plasticity in colorectal cancer
Year: 2026
Type: preprint
Study design: Observational Study
Abstract: Summary Colorectal cancer (CRC) has high phenotypic plasticity, but regulatory mechanisms of aberrant cell states are not well described. We investigated DNA methylation-based regulation of cancer cell-intrinsic transcriptomic heterogeneity in 1,183 multiregional primary tumor samples, liver metastases and tumor organoids. Most genes with strong methylation-transcriptomic association reflected canonical promoter hypermethylation and expression repression related to the CpG island methylator phenotype (CIMP). However, promoter hypomethylation and overexpression of APOLD1 and ELF5 identified two largely non-overlapping subgroups of canonical CIMP-negative CRCs enriched with stem-like and transit-amplifying cell states. APOLD1 tumors were further highly proliferative while ELF5 tumors were slow-cycling and associated with good survival in early-stage disease. Target genes showed patient-specific expression changes in matched primary-metastasis samples, and ELF5 aberrant metastases showed ex vivo sensitivity to putative targeting of stem cells by PI3K/mTOR inhibition, fetal de-differentiation and transition into non-canonical intestinal states. This implicates focal promoter hypomethylation in phenotypic plasticity in CRC metastasis.
Institutions: Oslo University Hospital, University of Oslo
Language: English
Subfield: Molecular Biology
Domain: Life Sciences
Open Access status: green
Funders: Kreftforeningen, Helse Sør-Øst RHF
Awards: G1738246870, G4556149590
OpenAlex ID: W7225348593
