The CDK8 antibody is a crucial tool for studying Cyclin-dependent kinase 8 (CDK8), a serine/threonine kinase within the CDK family. CDK8 forms part of the mediator complex, a multi-protein assembly that regulates RNA polymerase II-dependent transcription. Unlike canonical CDKs involved in cell cycle control, CDK8 primarily modulates gene expression by phosphorylating transcription factors (e.g., SMADs, STAT1) or components of the mediator complex, influencing pathways like Wnt/β-catenin, HIF-1α, and NF-κB. Dysregulation of CDK8 is implicated in cancers, including colorectal and breast cancer, where its overexpression often correlates with tumor progression, metastasis, and poor prognosis. CDK8 antibodies enable researchers to detect protein expression, localization, and interactions via techniques like Western blotting, immunohistochemistry, and co-immunoprecipitation. These antibodies are vital for elucidating CDK8's role in oncogenesis and its potential as a therapeutic target. However, challenges persist in ensuring antibody specificity due to homology among CDK family members. Recent studies highlight CDK8 inhibitors in preclinical trials, driving demand for reliable antibodies to validate target engagement and pharmacodynamic effects. Additionally, CDK8 antibodies contribute to understanding its non-oncogenic roles in metabolism and development. As research advances, these reagents remain essential for dissecting CDK8's multifaceted functions in health and disease.