Paraneoplastic antigen-like protein 5 (PNMA5)

Paraneoplastic antigen-like protein 5 (PNMA5) is encoded by the PNMA5 gene, which belongs to a family of paraneoplastic (onconeural) antigens. In primates, PNMA5 is preferentially expressed in association areas of the neocortex and limbic regions, particularly in excitatory neurons, and shows minimal expression in primary sensory areas. Unlike other family members, PNMA5’s gene sequence is highly divergent among mammals, suggesting specialized roles in primate neurobiology. In human cancer, especially epithelial ovarian cancer, PNMA5 is overexpressed and contributes to cell proliferation, migration, invasion, and cytoskeletal dynamics by acting via the Src→Erk1/2→Akt→GSK-3β pathway. Knockdown of PNMA5 suppresses these malignant behaviors and promotes apoptosis, highlighting its potential as a cancer biomarker and future drug target. No current therapies directly target PNMA5, but upstream pathway inhibitors may impact its function.

Other names

PNMA5Paraneoplastic antigen-like protein 5KIAA1934Tumor antigen BJ-HCC-25Paraneoplastic Ma antigen family member 5PNMA family member 5Paraneoplastic antigen family 5

Upstream regulation by Src kinase and Erk1/2 (phosphorylation of PNMA5); PNMA5 promotes downstream signaling via Akt and GSK-3β; Inhibition of PNMA5 (e.g., by siRNA or kinase inhibition) suppresses proliferation and promotes apoptosis in cancer cells