Abstract 2648: ZFP36L2 orchestrates stress adaptive plasticity during injury repair and metastasis

Abstract Phenotypic plasticity is emerging as a key hallmark of cancer progression, yet the molecular mechanisms of cancer cell reprogramming remain poorly understood. Using single cell RNA sequencing of synchronously surgically resected matched trios of normal colon, primary and metastatic tumors from colorectal cancer (CRC) patients, we recently demonstrated that CRC undergoes highly conserved sequential phenotypic transitions during tumor progression: (1) differentiated epithelial cells dedifferentiate into an LGR5+ intestinal stem cell (ISC) state during primary tumor initiation (2) disseminating cancer cells adopt an injury-induced fetal-like state and (3) at the metastatic site again dedifferentiate into LGR5+ ISC states, or alternatively undergo lineage plasticity into non-canonical neuroendocrine and squamous states, associated with aggressive behavior and poor clinical outcomes. Cancer cells thus dedifferentiate into LGR5+ ISC states at two steps during tumor progression. Seeking regulators of dedifferentiation, computational analysis identified the RNA binding protein ZFP36L2 as a stress-associated ISC state marker in normal intestinal crypts and in primary and metastatic tumors. In mouse models, we demonstrate that ZFP36L2 is dispensable for intestinal homeostasis, but is required for epithelial regeneration after DSS induced colitis or ISC ablation. Using human tissue samples, organoids and orthotopic mouse models, we show that loss of ZFP36L2 impairs progenitor regeneration and metastatic seeding—both of which require dedifferentiation into an intestinal stem cell state—while promoting proliferation and lineage plasticity into non-canonical states. Multiplex immunofluorescence staining of clinical samples demonstrates that loss of function mutations in ZFP36L2, found in 5-10% of human CRC, are associated with non-canonical differentiation in metastasis. Mechanistically, using HyperTRIBE and mRNA decay analysis, we show that ZFP36L2 binds to stress-associated mRNAs containing AU-rich 3’UTRs, in turn inducing the formation of dynamic phase-separated biomolecular condensates. Unexpectedly, IP-MS identifies the intestinal differentiation transcription factor CDX2, and the NCOR nuclear corepressor complex as lead ZFP36L2 interactors. Nuclear/cytoplasmic fractionation and super resolution live cell microscopy demonstrate that while ZFP36L2 is largely cytoplasmic, it can shuttle into the nucleus, where it induces transcriptional repression of the intestinal differentiation program through CDX2-NCOR complex formation and chromatin compaction. Together, our work identifies ZFP36L2 as a key orchestrator of stress-induced phenotypic plasticity, driving cellular dedifferentiation and epigenetic reprogramming essential for re-establishing the ISC state during metastatic seeding and wound healing. Citation Format: Qingwen Jiang, Manisha Raghavan, Britney Forsyth, Aileen Rodriguez, Cyrus Tam, Sasha Balkaran, Saskia Hartner, Morgan Lallo, Ahmed Mahmoud, Andrew Moorman, Jura Pintar, Dana Pe’er, Richard Koche, Quaid Morris, Joe Chan, Karuna Ganesh. ZFP36L2 orchestrates stress adaptive plasticity during injury repair and metastasis [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2025; Part 1 (Regular Abstracts); 2025 Apr 25-30; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2025;85(8_Suppl_1):Abstract nr 2648.