AnxA4

ANXA4 (Annexin A4) is a calcium-dependent phospholipid-binding protein of the annexin family that regulates membrane organization, membrane trafficking, and membrane permeability through reversible interactions with cellular phospholipid membranes^[1][2]. Mechanistically, ANXA4 undergoes calcium-dependent translocation between cytoplasmic and membrane compartments, a process linked to membrane remodeling, signal transduction, and cellular stress responses^[3][4]. ANXA4 has also been reported to interact with the NF-κB signaling machinery, including the p50 subunit, supporting a role in transcriptional regulation and tumor-associated signaling pathways^[5]. In disease settings, ANXA4 is frequently dysregulated in epithelial malignancies and has been associated with tumor cell proliferation, invasion, metastasis, and resistance to anticancer therapies^[1][2][6]. Experimental studies further indicate that ANXA4 contributes to plasma membrane repair and promotes invasive behavior in cancer models, particularly under conditions of membrane stress^[4]. Compared with related annexin isoforms, ANXA4 is characterized by its prominent epithelial expression pattern and distinct calcium-dependent membrane translocation behavior, which may confer specialized functions in membrane dynamics and cellular adaptation^[3][7]. For experimental applications, ANXA4 expression, localization, and membrane translocation are commonly used as molecular readouts for studies of membrane repair, tumor progression, and therapeutic resistance mechanisms^[1][3][4].