FOSL1 (FOS like 1) is an AP-1 transcription factor subunit that plays critical roles in cellular processes including wound healing, cancer progression, and tissue repair. In wound healing, FOSL1 serves as a critical driver of re-epithelialization, facilitating keratinocyte migration during the healing process 1. The protein functions as a dominant AP-1 family member that exerts its effects through selective association with Mediators to establish super-enhancers at target genes, driving expression of cancer stemness and pro-metastatic factors like SNAI2 2. FOSL1 coordinates with chr11 remodeler CHD2 to control expression of axon-guidance and synaptic genes in glioma cells, regulating neuron-glioma interactions that promote tumor growth 3. In inflammatory contexts, FOSL1 expression is regulated by CREB-mediated transactivation and contributes to pro-inflammatory macrophage programming following myocardial infarction 4. The protein also participates in resistance mechanisms to targeted therapies, where TEAD-mediated transcription of FOSL1 helps overcome KRAS dependency in cancer cells 5. Additionally, FOSL1 stability is regulated through lactylation-dependent interactions that prevent degradation and enhance genomic enrichment in drug-resistant melanoma 6. These findings establish FOSL1 as a master transcriptional regulator with significant therapeutic potential across multiple disease contexts.