MT1F (metallothionein 1F) is a small cysteine-rich protein that functions primarily in metal homeostasis and cellular protection against oxidative stress 1. As one of eight functional MT1 isoforms encoded on chromosome 16, MT1F binds various heavy metals through its high cysteine content and plays crucial roles in zinc ion homeostasis, detoxification of copper ions, and cellular responses to cadmium exposure 1. The protein's expression is transcriptionally regulated by metal regulatory transcription factor 1 (MTF1), which binds to MT1F promoters in response to specific stimuli like polyhexamethylene guanidine 2. MT1F demonstrates significant tumor suppressor properties, with decreased expression observed in various cancers including hepatocellular carcinoma, gastric cancer, and papillary thyroid carcinoma 345. Exogenous MT1F introduction inhibits cancer cell growth, reduces colony formation, and suppresses tumorigenicity in animal models 3. Additionally, MT1F contributes to antioxidant defense mechanisms, as its reduced expression correlates with increased reactive oxygen species accumulation 6. The protein is also involved in inflammatory responses, with expression levels increasing during labor and in response to pro-inflammatory stimuli in reproductive tissues 7. These findings establish MT1F as both a protective cellular factor and potential therapeutic target in cancer treatment.