Oncostatin M receptor

Oncostatin-M specific receptor subunit beta also known as the Oncostatin M receptor (OSMR) , is one of the receptor proteins for oncostatin M, that in humans is encoded by the OSMR gene.^[5][6]

OSMR is a member of the type I cytokine receptor family. This protein heterodimerizes with interleukin 6 signal transducer to form the type II oncostatin M receptor and with interleukin 31 receptor A to form the interleukin 31 receptor, and thus transduces oncostatin M and interleukin 31 induced signaling events.^[5]

Expression

OSMR is widely expressed across non-haematopoietic, hepatocytes, mesothelial cells, glial cells and epithelial cell types across various organs and mammary glands.^[7] OSM receptor is abundantly expressed on endothelial and stromal/fibroblast cells in the lung of mice.^[8]=

In vitro expression of OSMR  in fetal hepatocytes is upregulated by OSM stimulation.^[9]

OSMR expression has been shown to be induced by parathyroid hormone in osteoblasts and OSM.^[10][11]

Signaling

Intracellular cell signalling occurs as a consequence of extracellular binding of the ligand OSM to OSMR complexes, formed from dimerization with receptor subunits such as gp130. Activation of the OSMR-gp130 complex by OSM triggers Janus Kinase 1 (JAK1) and Jak2 cross phosphorylation of tyrosine residues on the intracellular receptor domain. Downstream signaling activation of the OSMR-gp130 complex  along the JAK1 pathway leads to IL-6 signalling which is linked with activation of the MAPK cascade, PI3K cascade and STAT3 activation.^[12][13]

OSM induced recruitment of

The oncostatin M receptor is associated with primary cutaneous amyloidosis.^[15]

OSM signaling via the OSMR is believed to play an important role in bone turnover as Mice lacking the OSMR receptor have osteopetrotic phenotypes.^[16] Lack of OSMRβ activity has also been linked to adipose tissue inflammation and insulin resistance preceding obesity.^[17]

OSM in-vivo regulation of hematopoiesis, through stimulation of stromal cells & hematopoietic progenitors - megakaryocytic and erythrocytic progenitors, is carried out by the OSMRβ receptor.^[18]

Heart Disease

Inhibition of the OSMRβ extracellular subunit has been shown has been shown to prevent OSM-mediated down-regulation of myoglobin in cardiomyocytes and related apoptosis of cardiomyocytes in inflammatory heart failure.^[19]

OSMRβ is not only overexpressed in patients with chronic dilated cardiomyopathy but has been shown to control dedifferentiation and loss of sarcomeric structures in myocardial infarction and dilated cardio myopathy.^[20] OSM and OSMRβ mediated dedifferentiation  has been shown to increase chances of survival after acute myocardial damage but poor survival rates and compromised pump functions in chronic disease states.^[20]

Cancer

OSMR activates STAT3 and transforming growth factor β (TGF-β) effector SMAD3 to regulate expression of genes responsible for inducing a mesenchymal/CSC phenotype.^[21]

OSM-induced biological effects on breast tumor– derived cell lines were specifically mediated through the gp130/OSMRB complex.^[22]

the OSM receptor (OSMR) is overexpressed in cervical squamous cell carcinomas and, independent of tumor stage, is associated with adverse clinical outcomes and higher relative risk of death.^[23]

OSM and OSMRβ are co-expressed and lead to STAT 3 activation malignant human ovarian epithelial cells.^[24]

The OSMR β  promoter gene is highly methylated in primary Colorectal Cancer tissues and  fecal DNA, it is a highly specific diagnostic biomarker of Colorectal Cancer.^[25]

References