PNMA2

PNMA2 encodes Paraneoplastic Ma Antigen 2 (Ma2, alias CAG-3), a member of the PNMA family expressed primarily in the brain and testes. It regulates neuronal differentiation and transcriptional processes. Aberrant expression in tumors (e.g., lung, testicular cancers) triggers anti-Ma2 autoantibody production, leading to paraneoplastic neurological syndromes (PNS).
Anti-Ma2 antibodies disrupt neuronal function via immune-mediated pathways, linking to paraneoplastic encephalomyelitis (PEM) and Lambert-Eaton myasthenic syndrome. Current therapies include corticosteroids and IVIG to suppress antibody damage; targeted agents against PNMA2-positive tumors are under preclinical investigation.