ANKRD42 is an ankyrin repeat domain protein with emerging roles in disease pathogenesis. At the molecular level, ANKRD42 possesses NF-κB binding capacity and cyclin-dependent protein serine/threonine kinase inhibitor activity 1. The protein functions primarily through circular RNA (circRNA) mechanisms in lung disease. In idiopathic pulmonary fibrosis (IPF), circANKRD42 is generated via hnRNPL-activated back-splicing and acts as a competing endogenous RNA (ceRNA) that sequesters miR-324-5p and miR-136-5p, ultimately promoting YAP1 nuclear accumulation and fibrotic gene transcription through TEAD binding 2. In colorectal cancer, ANKRD42 operates as a critical regulator of metastatic progression through epithelial-mesenchymal transition (EMT). CRISPR-Cas9 screening identified ANKRD42 as pivotal for CRC liver metastasis, with elevated expression in metastatic lesions correlating with enhanced tumor cell migration and invasion 3. ANKRD42 depletion downregulates EMT-associated genes (CDH2, SNAI2), suppressing metastatic capacity in patient-derived organoid models 3. Additionally, circulating ANKRD42 expression following hematopoietic stem cell transplantation serves as a prognostic biomarker, being part of an 11-gene transcriptomic signature that predicts sepsis development 2-7 days before clinical onset 4. Collectively, ANKRD42 represents a multifunctional protein with therapeutic potential in fibrotic and neoplastic diseases.