ZC3HAV1 (zinc finger CCCH-type containing, antiviral 1) is a multifunctional protein serving as a positive regulator of innate antiviral immunity and a potential oncogenic driver. Primary Function: ZC3HAV1 acts as a potent antiviral effector by binding viral RNAs enriched in CpG dinucleotides and promoting their degradation 1. It enhances RIG-I signaling by promoting RIG-I oligomerization and ATPase activity, leading to IRF3 and NF-κB activation and robust type I interferon production 2. Additionally, ZC3HAV1 potentiates STING activation by facilitating STING oligomerization and endoplasmic reticulum-to-Golgi translocation, further amplifying antiviral responses 2. Mechanism: ZC3HAV1 associates with viral RNAs through its zinc finger domains and coordinates with cofactors like TRIM25 to restrict viral replication 3. Interestingly, ZC3HAV1 also dampens T cell cytokine production by binding 3' UTRs of IFNG, TNF, and IL2 mRNAs, thereby temporally regulating immune responses 4. Disease Relevance: While protective against viruses including SARS-CoV-2, HSV-1, and HIV-1, ZC3HAV1 overexpression drives pancreatic cancer proliferation and metastasis by directly binding and upregulating KRAS, activating pro-tumoral MAPK signaling 5. Clinical Significance: ZC3HAV1 represents a dual-edged therapeutic target—inhibition may benefit STING-dependent inflammatory diseases, while modulation could impact cancer treatment strategies.