ABSTRACT
Bone is one of the preferential target organs of cancer metastasis. Bone metastasis is associated with various complications, of which bone pain is most common and debilitating. The cancer-associated bone pain (CABP) is induced as a consequence of increased neurogenesis, reprogramming and axonogenesis of sensory nerves (SNs) in harmony with sensitization and excitation of SNs in response to the tumor microenvironment created in bone. Importantly, CABP is associated with increased mortality, of which precise cellular and molecular mechanism remains poorly understood. Bone is densely innervated by autonomic nerves (ANs) (sympathetic and parasympathetic nerves) and SNs. Recent studies have shown that the nerves innervating the tumor microenvironment establish intimate communications with tumors, producing various stimuli for tumors to progress and disseminate. In this review, our current understanding of the role of SNs innervating bone in the pathophysiology of CABP will be overviewed. Then the hypothesis that SNs facilitate cancer progression in bone will be discussed in conjunction with our recent findings that SNs play an important role not only in the induction of CABP but also the progression of bone metastasis using a preclinical model of CABP. It is suggested that SNs are a critical component of the bone microenvironment that drives the vicious cycle between bone and cancer to progress bone metastasis. Suppression of the activity of bone-innervating SNs may have potential therapeutic effects on the progression of bone metastasis and induction of CABP.
ABSTRACT
BACKGROUND:The V-ATPase a3 transport system plays a crucial role on bone resorption mechanism of the osteoclasts. OBJECTIVE:To observe the expression of V-ATPase a3 transport system in fracture repair and the effect of V-ATPase a3 transport system inhibitor on fracture healing. METHODS:We retrieved related literatures in the periodicals database with the key words, and screen them according to the inclusion criteria. The literatures were included in this study after the evaluation of quality. RESULTS AND CONCLUSION:V-ATPase a3 transport system widely exists in the cytoplasm membrane and organel e membrane of eukaryotic cells. V-ATPase a3 has two structural domains:V0 and V1. V0 structural domain is the proton transport channel, V1 structural domain is mainly the hydrolysis of ATP. V-ATPase a3 transport system focuses on the fril ed edge of osteoclasts, H+is transported to form a high concentration, dissolves inorganic minerals and provides the acidic environment for hydrolytic enzymes, thus being involved in bone resorption. So V-ATPase a3 transport system is selected as the research target in the fracture repair and reshape.
ABSTRACT
The neurological movement disorder dystonia is an umbrella term for a heterogeneous group of related conditions where at least 20 monogenic forms have been identified. Despite the substantial advances resulting from the identification of these loci, the function of many DYT gene products remains unclear. Comparative genomics using simple animal models to examine the evolutionarily conserved functional relationships with monogenic dystonias represents a rapid route toward a comprehensive understanding of these movement disorders. Current studies using the invertebrate animal models Caenorhabditis elegans and Drosophila melanogaster are uncovering cellular functions and mechanisms associated with mutant forms of the well-conserved gene products corresponding to DYT1, DYT5a, DYT5b, and DYT12 dystonias. Here we review recent findings from the invertebrate literature pertaining to molecular mechanisms of these gene products, torsinA, GTP cyclohydrolase I, tyrosine hydroxylase, and the alpha subunit of Na+/K ATPase, respectively. In each study, the application of powerful genetic tools developed over decades of intensive work with both of these invertebrate systems has led to mechanistic insights into these human disorders. These models are particularly amenable to large-scale genetic screens for modifiers or additional alleles, which are bolstering our understanding of the molecular functions associated with these gene products. Moreover, the use of invertebrate models for the evaluation of DYT genetic loci and their genetic interaction networks has predictive value and can provide a path forward for therapeutic intervention.
ABSTRACT
[Objective] To investigate the difference of bone Absorption function of the rat osteoclast(OC) in different cultural methods, and the difference in the levels of mRNA expression of bone Absorption key gene, ATPase a3 gene, and provide the basis for further investigation on the OC in vitro. [Methods] with mechanical separation method, mature osteoclast was separated from inner wall of 24 hours newborn rat long bones medullary cavity; and induction culture methods, bone marrow cell was induced to osteoclast like cell(OLC) by using 1,25(OH)2D3.The morphological and functional change of osteoclast was observed and the difference in the level of ATPase a3 mRNA expression was determined.[ Result]OC and OLC are multinucleated giant cells, which can be stained positive by potartrate resistant acid phosphatase(TRAP), and can form bone Absorption lacuna. The number of OLC in induction method is more than in mechanical separation method, but bone Absorption lacuna is smaller and shallower than the early stage of induction. The late stage of OCL is extremely similar to OC. There is no significant difference of ATPase a3 mRNA expression from the cells between mechanical separation 8 hour and induction culture 6 days, but either of them is significantly less than inducing 8 days. [Conclusion]Induction method can produce a large number of OLC which is superior to mechanical separation method, but its bone resorption function is weaker in the earlier stage, because bone resorption function is associated with the number of nucleus. The late stage of OCL is extremely similar to OC of mechanical separation method. And it can be used in any experiments.
