FNTB encodes the beta subunit of farnesyltransferase (FTase), a heterodimeric enzyme essential for post-translational farnesylation of proteins containing a CAAX motif 1. The protein catalyzes attachment of a farnesyl group to key cellular proteins including RAS family members, nuclear lamins, and regulatory kinases, enabling their proper membrane localization and function 1. FNTB expression is transcriptionally regulated by the OCT-1 transcription factor 2 and is responsive to inflammatory signals and metabolic stress 34. Mechanistically, FNTB loss impairs nuclear laminA maturation and nuclear envelope integrity, triggering DNA damage responses and cardiomyocyte senescence 4. In cancer contexts, FNTB promotes cell migration and proliferation through substrate prenylation; for example, FNTB-mediated prenylation of PALM2 activates ezrin signaling in esophageal cancer cells 5. In hepatocellular carcinoma, FNTB acts downstream of SPDL1 to promote tumor growth and drug resistance 6. Clinically, FNTB dysfunction is implicated in multiple malignancies and cardiac disease. Lipid overload suppresses FNTB expression in cardiomyocytes, contributing to lipotoxic cardiomyopathy and fibrosis 4. FNTB is associated with osteoporosis risk 7. FTase inhibitors targeting FNTB are under clinical investigation as cancer therapeutics and demonstrate anti-inflammatory effects in periodontal disease models 3.