Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0005940 (bone disease)
 7,459 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Multiple Myeloma (MM) is a malignant disease of terminally differentiated B cells. It most likely originates in a B cell which has traversed the germinal center and has been exposed there extensively to antigens based on the high number of somatic mutations in the complementarity determining regions. The cell of origin is either a plasmablast, or more likely, a memory B-cell. Typically MM goes through different phases from indolent (MGUS, smoldering myeloma) to overt myeloma and then to a fulminant phase, characterized by extramedullary manifestations, high LDH, immature morphology and increased proliferation rate. In the indolent phase, the disease already has acquired major cytogenetic abnormalities as demonstrated by FISH and DNA flow cytometry. It has a gene pattern very similar to myeloma cells on gene array analysis. In the early stages of overt MM, the myeloma cells are completely dependent upon the micro-environment for their growth and survival. The interaction between myeloma cells and micro-environment causes bone disease, genetic instability and more importantly, drug-resistance, which is caused by upregulation of anti-apoptotic factors, resistance to apoptosis induced by FAS and TRAIL activation, and by cell adhesion-induced growth arrest. In this phase of the disease, MM is susceptible to chemotherapy, if delivered with adequate intensity. In the fulminant phase of MM, myeloma cells have acquired sufficient genetic alternations to become completely independent of the micro-environment which allows them to grow at extramedullary sites. Because of the many DNA breaks necessary for immature B cells to become mature plasma cells, B cells already have inherent genetic instability. DNA breaks are necessary for VDJ recombinations, somatic mutations and isotype switching and it is therefore not surprising that genetic alternations frequently occur at the Ig heavy chain site at 14q32, which is abnormal in three quarters of myeloma patients. Some of the translocations with 14q32 involve terminal fragments of chromosomes and can not be diagnosed with standard cytogenetics. Cytogenetic abnormalities are found in 30-35% of newly diagnosed patients and require sufficient proliferation of MM cells to find enough analyzable mitoses. The cytogenetic abnormalities are typically complex, involving > or = 3 chromosomes in 80% of patients. Almost all chromosomes can be involved in deletions, additions or translocations of genetic material. Our group has repeatedly stressed the prognostic significance of chromosome 13 deletion by conventional cytogenetics. The role of chromosome 13 deletion by FISH. is less clear. In addition to chromosome 13 deletion, the presence of a hypodiploid or hypotetraploid karyotye also carries a poor prognosis. Frequently, deletions of chromosome 13 and hypodiploidy go hand in hand. It remains unclear what specific gene confers the poor prognosis to patients with deletion 13. The issues of bone disease, drug resistance and cytogenetics will be addressed in detail during this presentation.
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PMID:New insights into role of microenvironment in multiple myeloma. 1243 Aug 76

Abnormal antioxidative capabilities were observed in the pathogenesis of steroid-induced osteoporosis (SIOP). Ferroptosis is a recently discovered type of cell death that is characterized by the overproduction of ROS in response to GPX4 and system Xc- downregulation, which is mediated by an Fe2+ fenton reaction. However, investigations focusing on the relationship between ferroptosis and steroid-induced bone disease remain limited. In the present study, high-dose dexamethasone was used to establish a mouse SIOP model, and extracellular vesicles extracted from bone marrow-derived endothelial progenitor cells (EPC-EVs) alleviated the pathological changes in SIOP via microtomography (micro-CT), with elevations in bone volume (BV), bone surface (BS), trabecular thickness (Tb.Th), and trabecular connectivity density (Conn-D) and decreases in trabecular separation (Tb.sp) and the structure model index (SMI). Histopathological analysis, such as haematoxylin and eosin (HE) and Masson staining, showed that EPC-EVs treatment increased the volume and density of the trabecular bone and bone marrow. RNA sequencing (RNA-seq) and bioinformatics analysis revealed subcellular biological alterations upon steroid and EPC-EVs treatment. Compared with the control, high-dose dexamethasone downregulated GPX4 and system XC-, and the Kyoto Encyclopedia of Genes and Genomes (KEGG)-based gene set enrichment analysis suggested that the ferroptotic pathway was activated. In contrast, combination treatment with EPC-EVs partly reversed the KEGG-mapped changes in the ferroptotic pathway at both the gene and mRNA expression levels. In addition, alterations in ferroptotic marker expression, such as SLC3A2, SLC7A11, and GPX4, were further confirmed by RNA-seq. EPC-EVs were able to reverse dexamethasone treatment-induced alterations in cysteine and several oxidative injury markers, such as malondialdehyde (MDA), glutathione (GSH), and glutathione disulphide (GSSG) (as detected by ELISA). In conclusion, EPC-EVs prevented mouse glucocorticoid-induced osteoporosis by suppressing the ferroptotic pathway in osteoblasts, which may provide a basis for novel therapies for SIOP in humans.
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PMID:Extracellular vesicles from endothelial progenitor cells prevent steroid-induced osteoporosis by suppressing the ferroptotic pathway in mouse osteoblasts based on bioinformatics evidence. 3169 92