Project description:Bone metastasis is one of the most frequent metastases of NSCLC and leads to poor prognosis. It has been reported that high expression of BMP2 in NSCLC indicates poor survival, but whether BMP2 contributes to NSCLC bone metastasis remains largely unknown.
Project description:Enhanced BMP or canonical Wnt (cWnt) signaling are therapeutic strategies employed to enhance bone formation and fracture repair, but the mechanisms each pathway utilizes to specify cell fate of bone-forming osteoblasts remain poorly understood. Among all BMPs expressed in bone, we find that singular deficiency of Bmp2 blocks the ability of cWnt signaling to specify osteoblasts from limb bud or bone marrow progenitors. When exposed to cWnts, Bmp2-deficient cells fail to progress through the Runx2/Osx1 checkpoint and thus do not upregulate multiple genes controlling mineral metabolism in osteoblasts. Cells lacking Bmp2 after induction of Osx1 differentiate normally in response to cWnts, supporting pre-Osx1+ osteoprogenitors as a critical source and target of BMP2. Our analysis furthermore reveals Grainyhead-like 3 (Grhl3) is to date an unidentified transcription factor in the osteoblast gene regulatory network that is induced during bone development and bone repair, and acts upstream of Osx in a BMP2-dependent manner. The Runx2/Osx1 transition therefore receives critical regulatory inputs from BMP2 that are not compensated for by cWnt signaling, and this is mediated at least in part by induction and activation of Grhl3.
Project description:We performed microarray analysis with two different chip platforms, Affymetrix and Agilent, on bone metastasis samples from breast cancer patients with only bone metastases and metastases in bone and visceral organs. We collected bone metastases biopsies from breast cancer patients with only bone metastases and metastases in bone and visceral organs. RNA was extracted from these samples and subjected to microarray analysis with the Agilent platform. Data were compared with a signsture obtained with the Affymetrix platform, to obtain a signature of differentially regulated genes between the two groups of patients This Series represents the Agilent data only. The Affymetrix data are provided in GEO Series GSE11078.
Project description:We performed microarray analysis with two different chip platforms, Affymetrix and Agilent, on bone metastasis samples from breast cancer patients with only bone metastases and metastases in bone and visceral organs.
Project description:The role of bone morphogenetic protein 2 (Bmp2)in regulating the transformation of the uterine stroma during embryo implantation in the mouse was investigated by the conditional ablation of Bmp2 in the uterus using the (PR-cre) mouse. Keywords: Genetic modification
Project description:Reconstruction of bone defects and compensation of deficient repair mechanisms represent important goals within the field of regenerative medicine and require novel safe strategies for translation into the clinic. Therefore, we generated a nonviral osteogenic gene therapeutic (hybrid) vector system, combining an improved bone morphogenetic protein 2 (BMP2) gene cassette and pro-osteogenic microRNAs. The hybrid vectors were tested for their functionality and osteogenic differentiation potential in C2C12 and C3H/10T1/2 via alkaline phosphatase enzyme activity assay, enzyme-linked immunosorbent assay and reverse transcription quantitative polymerase chain reaction analysis of miRNA and osteogenic marker expression. In a mouse ectopic bone formation model, osteoinduction in transfected muscle tissue was analysed via micro computed tomography scans and histological staining. All tested hybrid vector systems led to an increase in BMP2 protein overexpression in C2C12 and C3H/10T1/2, when compared with miRNA-lacking constructs. Incorporated miRNAs were found to be efficiently upregulated. Distinct intra- and extracellular localization preferences were observed. The hybrid vector consisting of BMP2 and miR-590 revealed highest potential of inducing osteogenic differentiation. The favourable effect of combining overexpression of BMP2 and miRNAs has been shown in vitro and in vivo. Induction of mineralization was observed in an ectopic bone mouse model, although high variability in terms of size and shape indicates potential for improvement regarding plasmid administration and retention. We believe this study contributes in a valuable way to the preclinical knowledge of nonviral gene therapy for tissue regeneration. Also, we hope to encourage additional research on multi-target gene therapeutic approaches.
Project description:Bone morphogenetic proteins (BMPs) regulate many aspects of skeletal development, including osteoblast and chondrocyte differentiation, cartilage and bone formation, and cranial and limb development. Among them, BMP2, one of the most potent osteogenic signaling molecules, stimulates osteoblast differentiation.
Project description:The expression of Prx1 has been used as a marker to define the skeletal stem cells (SSC) populations found within the bone marrow and periosteum that contribute to bone regeneration. However, Prx1 expressing SSCs (Prx1-SSCs) are not restricted to the bone compartments, but are also located within the muscle and able to contribute to ectopic bone formation. Little is known however, about the mechanism(s) regulating Prx1-SSCs that reside in muscle and how they participate in bone regeneration. This study compared both the intrinsic and extrinsic factors of the periosteum and muscle derived Prx1-SSCs and analyzed their regulatory mechanisms of activation, proliferation, and skeletal differentiation. There was considerable transcriptomic heterogeneity in the Prx1-SSCs found in muscle or the periosteum however in vitro cells from both tissues show tri-lineage (adipose, cartilage and bone) differentiation. At homeostasis, periosteal derived Prx1 cells were proliferative and low levels of BMP2 were able to promote their differentiation, while the muscle derived Prx1 cells were quiescent and refractory to comparable levels of BMP2 that promoted periosteal cell differentiation. The transplantation of Prx1-SCC from muscle and periosteum into either the same site from which they were isolated, or their reciprocal sites showed that periosteal cell transplanted onto the surface of bone tissues differentiated into bone and cartilage cells but was incapable of similar differentiation when transplanted into muscle. Prx1-SSCs from the muscle showed no ability to differentiate at either site of transplantation. Both fracture and ten times the BMP2 dose was needed to promote muscle-derived cells to rapidly enter the cell cycle as well as undergo skeletal cell differentiation. This study elucidates the diversity of the Prx1-SSC population showing that cells within different tissue sites are intrinsically different. While muscle tissue must have factors that promote Prx1-SSC to remain quiescent, either bone injury or high levels of BMP2 can activate these cells to both proliferate and undergo skeletal cell differentiation. Finally, these studies raise the possibility that muscle SSCs are potential target for skeletal repair and bone diseases.
Project description:TGF-beta is a known driver of epithelial-mesenchymal transition (EMT) which is associated with tumor aggressiveness and metastasis. However, EMT has not been fully explored in clinical specimens of castration-resistant prostate cancer (CRPC) metastases. To assess EMT in CRPC, gene expression analysis was performed on 149 visceral and bone metastases from 62 CRPC patients and immunohistochemical analysis was performed on 185 CRPC bone and visceral metastases from 42 CRPC patients. In addition, to assess the potential of metastases to seed further metastases the mitochondrial genome was sequenced at different metastatic sites in one patient. TGF-beta was increased in bone versus visceral metastases. While primarily cytoplasmic; nuclear and cytoplasmic Twist were significantly higher in bone than in visceral metastases. Slug and Zeb1 were unchanged, with the exception of nuclear Zeb1 being significantly higher in visceral metastases. Importantly, nuclear Twist, Slug, and Zeb1 were only present in a subset of epithelial cells that had an EMT-like phenotype. Underscoring the relevance of EMT-like cells, mitochondrial sequencing revealed that metastases could seed additional metastases in the same patient. In conclusion, while TGF-beta expression and EMT-associated protein expression is present in a considerable number of CRPC visceral and bone metastases, nuclear Twist, Slug, and Zeb1 localization and an EMT-like phenotype (elongated nuclei and cytoplasmic compartment) was only present in a small subset of CRPC bone metastases. Mitochondrial sequencing from different metastases in a CRPC patient provided evidence for the seeding of metastases from previously established metastases, highlighting the biological relevance of EMT-like behavior in CRPC metastases.