BMP2 variants in the risk of ankylosing spondylitis

Elevated BMPR2 expression amplifies osteoblast differentiation in ankylosing spondylitis

Objective

Bone morphogenetic protein receptor type 2 (BMPR2) has been associated with radiographic changes in ankylosing spondylitis (AS), but further characterization of the cellular signaling pathway in osteoprogenitor (OP) is not clearly understood. The aim of this study was to investigate the expression of BMPR2 and bone morphogenetic protein 2 (BMP2)-mediated responsibility in AS.

Methods

We collected 10 healthy control (HC) and 14 AS-OPs derived from facet joints. Subsequently, we then conducted RNA sequencing with two samples per group and selected BMP-related genes. Facet joint tissues and derived primary OPs were evaluated by validation of selected RNA sequencing data, immunohistochemistry, and comparison of osteogenic differentiation potential.

Results

Based on RNA-sequencing analysis, we found that BMPR2 expression is higher in AS-OPs compared to in HC-OPs. We also validated the increased BMPR2 expression in facet joint tissues with AS and its derived OPs in messenger RNA and protein levels. Additionally, primary AS-OPs showed much greater response to osteogenic differentiation induced by BMP2 and a higher capacity for smad1/5/8-induced RUNX2 expression compared to HCs.

Conclusion

The expression of BMPR2 was found to be significantly increased in facet joint tissues of patients with AS. These findings suggest that BMPR2 may play a role in the BMP2-mediated progression of AS.

BMP2 as a promising anticancer approach: functions and molecular mechanisms

Bone morphogenetic protein 2 (BMP2), a pluripotent factor, is a member of the transforming growth factor-beta (TGF-β) superfamily and is implicated in embryonic development and postnatal homeostasis in tissues and organs. Experimental research in the contexts of physiology and pathology has indicated that BMP2 can induce macrophages to differentiate into osteoclasts and accelerate the osteolytic mechanism, aggravating cancer cell bone metastasis. Emerging studies have stressed the potent regulatory effect of BMP2 in cancer cell differentiation, proliferation, survival, and apoptosis. Complicated signaling networks involving multiple regulatory proteins imply the significant biological functions of BMP2 in cancer. In this review, we comprehensively summarized and discussed the current evidence related to the modulation of BMP2 in tumorigenesis and development, including evidence related to the roles and molecular mechanisms of BMP2 in regulating cancer stem cells (CSCs), epithelial-mesenchymal transition (EMT), cancer angiogenesis and the tumor microenvironment (TME). All these findings suggest that BMP2 may be an effective therapeutic target for cancer and a new marker for assessing treatment efficacy.