Cytoplasmic activation-associated protein 1 (CAPRIN1) (CAPRIN1)

CAPRIN1 (Cytoplasmic activation-associated protein 1) is a highly conserved RNA-binding protein that plays a critical role in regulating the transport, translation, and stability of mRNAs involved in cell proliferation and synaptic plasticity [11, 18, 20]. It is a key component of stress granules, which are cytoplasmic aggregates that form in response to cellular stress to sequester and protect mRNAs [3, 5, 10, 20]. In healthy tissues, CAPRIN1 is primarily expressed in the brain and dividing cells, but it is significantly overexpressed on the cell membrane of various solid tumors, including gastric, breast, and pancreatic cancers [1, 6, 8, 14]. This tumor-specific membrane expression makes it an attractive therapeutic target, as it promotes oncogenic processes such as cell cycle progression, metastasis, and immune evasion by upregulating checkpoint proteins like PD-L1 [3, 12]. Therapeutically, CAPRIN1 is targeted by monoclonal antibodies such as TRK-950, which is designed to induce antibody-dependent cellular cytotoxicity (ADCC) and phagocytosis (ADCP) against cancer cells [1, 2, 8]. Clinical studies have demonstrated that TRK-950 is well-tolerated and shows potential antitumor activity in patients with advanced solid tumors [1, 6, 14]. Beyond oncology, mutations in the CAPRIN1 gene are associated with neurodevelopmental disorders, including intellectual disability and autism, as well as neurodegenerative conditions like early-onset ataxia [9, 13]. Consequently, while CAPRIN1 is a promising target for cancer immunotherapy, its essential role in the central nervous system necessitates careful monitoring of potential neurological safety concerns during drug development [5, 16].

Other names

GPIAP1GPI-AP1M11S1RNG105p137GPICell cycle associated protein 1

Antibody-dependent cellular cytotoxicity (ADCC), Antibody-dependent cellular phagocytosis (ADCP), and inhibition of tumor cell proliferation and metastasis.