Transmembrane glycoprotein NMB (GPNMB)

Transmembrane glycoprotein NMB (GPNMB), also known as osteoactivin or DC-HIL, is a type I transmembrane glycoprotein that plays a diverse role in cell adhesion, migration, and tissue remodeling [UniProt Q14974]. It is highly expressed in various tissues including the skin, bone, and hematopoietic system, where it facilitates osteoblast differentiation and contributes to the formation of melanosomes [PMID: 15302636]. In immunology, GPNMB acts as a potent negative regulator of T-cell activation, often exploited by tumors to escape immune surveillance [PMID: 17312134]. The protein is significantly overexpressed in several aggressive malignancies, most notably melanoma, glioblastoma, and triple-negative breast cancer, making it a viable target for therapeutic intervention [PMID: 24519946]. Clinical efforts have primarily focused on antibody-drug conjugates like glembatumumab vedotin, which utilize GPNMB as a cellular anchor to deliver cytotoxic payloads directly into tumor cells [PMID: 32669460]. Beyond oncology, GPNMB has emerged as a critical biomarker for lysosomal storage diseases such as Gaucher disease and is being investigated for its role in neurodegenerative pathology, including amyotrophic lateral sclerosis [PMID: 26363004].

Other names

OsteoactivinGlycoprotein non-metastatic melanoma protein BHGFINDC-HILDendritic cell-heparin integrin ligandGlycoprotein (transmembrane) nmb

Antibody-drug conjugate (ADC) mediated delivery of monomethyl auristatin E (MMAE) to GPNMB-expressing tumor cells; inhibition of T-cell suppression by blocking the DC-HIL/syndecan-4 pathway; induction of antibody-dependent cellular cytotoxicity (ADCC).