Search results for "Cathepsin"
showing 10 items of 170 documents
Expression of Matrix-Degrading Cysteine Proteinase Cathepsin K in Cholesteatoma
2001
Cholesteatoma is a nonneoplastic lesion of the middle ear space or mastoid that is histologically characterized by a progressive bone erosion of the ossicles and surrounding bone. Several matrix-degrading enzymes have been implicated as mediators of this bone erosion. Because the novel cysteine proteinase cathepsin K has been shown to play a central role in bone resorption, we examined the expression of this enzyme in tissue specimens of cholesteatoma. Tissue specimens of 9 patients with cholesteatoma were obtained during middle-ear surgery. Expression of cathepsin K mRNA was determined by RT-PCR using specific primers. Immunohistochemical analysis of cathepsin K protein expression in tissu…
The effect of surgical suture material on osteoclast generation and implant-loosening
2020
Background: Implant loosening - either infectious or aseptic- is a still a major complication in the field of orthopaedic surgery. In both cases, a pro-inflammatory peri-prosthetic environment is generated by the immune system - either triggered by bacteria or by implant wear particles - which leads to osteoclast differentiation and osteolysis. Since infectious cases in particular often require multiple revision surgeries, we wondered whether commonly used surgical suture material may also activate the immune system and thus contribute to loss of bone substance by generation of osteoclasts. Methods: Tissue samples from patients suffering from infectious implant loosening were collected intr…
Lysosomal aspartic and cysteine proteinases serum levels in patients with pancreatic cancer or pancreatitis
1997
Lysosomal cathepsins D (CD), B (CB), and L (CL) serum levels were determined by immunoassays in patients with chronic (CHP) or acute (AP) pancreatitis and in patients with ductal pancreatic carcinoma (DPC) and correlated with some biological and clinical parameters of this tumor. CB serum concentrations significantly higher than those measured in healthy subjects (NS) were observed in CHP, AP, and DPC patients (p < 0.01). However, no significant difference was noted among these groups. Increased CL serum levels were evident only in cancer patients compared to NS, AP, or CHP groups (p < 0.05), while no difference was observed among these groups. Elevated CD serum values were observed i…
Adhesive and invasive features in gliomas
2000
Summary This study aims at the in situ identification of factors mediating glioma cell invasion requiring adhesion, extracellular matrix degradation, and migration. Fortyfive gliomas (astrocytomas, glioblastomas, oligodendrogliomas, and mixed gliomas) were investigated for the immunohistochemical expression of the membrane protein CD44s, the basal lamina proteins laminin, collagen IV, and fibronectin, the lectin galectin-3 recognizing tenascin and N-CAM, as well as for the matrix-degrading enzymes metalloproteinases MMP-2, MMP-9, and cathepsin D. Besides vessels expressing basal lamina proteins, tenascin, MMP-2, MMP-9, and galectin-3, tumor cells revealed strong immunoreactivity for CD44s, …
Effects of zoledronic acid on proteinase plasma levels in patients with bone metastases.
2006
Background: The effects of the bisphosphonate derivative zoledronic acid (ZA) on the > circulating levels of matrix metalloproteinase-2 (MMP-2), matrix metallo-proteinases-9 > (MMP-9), cathepsin B (Cath B) and urokinase-type plasminogen activator (uPA) in > patients with bone metastasis (BMTS) and the possible correlation with the symptomatic > response induced by this drug in these patients were evaluated. Patients and Methods: > Proteinase levels were determined by enzyme-linked immunosorbent assay (ELISA) in the > plasma of 30 patients with painful bone metastases from breast or prostate cancer > undergoing multiple treatment with ZA (4 mg i.v., every 4 weeks). Healthy subjects > (HS) of…
Bioencapsulation of living bacteria (Escherichia coli) with poly(silicate) after transformation with silicatein-α gene
2007
Bioencapsulation is an intriguing way to immobilize biological materials, including cells, in silica, metal-oxides or hybrid sol-gel polymers. Until now only the sol-gel precursor technology was utilized to immobilize bacteria or yeast cells in silica. With the discovery of silicatein, an enzyme from demosponges that catalyzes the formation of poly(silicate), it became possible to synthesize poly(silicate) under physiological (ambient) conditions. Here we show that Escherichia coli can be transformed with the silicatein gene, its expression level in the presence of isopropyl beta-D-thiogalactopyranoside (IPTG) can be efficiently intensified by co-incubation with silicic acid. This effect co…
The Extracellular Vesicles of the Helminth Pathogen, Fasciola hepatica : Biogenesis Pathways and Cargo Molecules Involved in Parasite Pathogenesis
2015
Extracellular vesicles (EVs) released by parasites have important roles in establishing and maintaining infection. Analysis of the soluble and vesicular secretions of adult Fasciola hepatica has established a definitive characterisation of the total secretome of this zoonotic parasite. Fasciola secretes at least two sub-populations of EVs that differ according to size, cargo molecules and site of release from the parasite. The larger EVs are released from the specialised cells that line the parasite gastrodermus and contain the zymogen of the 37 kDa cathepsin L peptidase that performs a digestive function. The smaller exosome-like vesicle population originate from multivesicular bodies with…
Cathepsin L in metastatic bone disease: therapeutic implications
2010
AbstractCathepsin L is a lysosomal cysteine proteinase primarily devoted to the metabolic turnover of intracellular proteins. However, accumulating evidence suggests that this endopeptidase might also be implicated in the regulation of other important biological functions, including bone resorption in normal and pathological conditions. These findings support the concept that cathepsin L, in concert with other proteolytic enzymes involved in bone remodeling processes, could contribute to facilitate bone metastasis formation. In support of this hypothesis, recent studies indicate that cathepsin L can foster this process by triggering multiple mechanisms which, in part, differ from those of t…
miR-29b negatively regulates human osteoclastic cell differentiation and function: Implications for the treatment of multiple myeloma-related bone di…
2013
Skeletal homeostasis relies upon a fine tuning of osteoclast (OCLs)-mediated bone resorption and osteoblast (OBLs)-dependent bone formation. This balance is unsettled by multiple myeloma (MM) cells, which impair OBL function and stimulate OCLs to generate lytic lesions. Emerging experimental evidence is disclosing a key regulatory role of microRNAs (miRNAs) in the regulation of bone homeostasis suggesting the miRNA network as potential novel target for the treatment of MM-related bone disease. Here, we report that miR-29b expression decreases progressively during human OCL differentiation in vitro. We found that lentiviral transduction of miR-29b into OCLs, even in the presence of MM cells,…
Circulating cathepsin K and cystatin C in patients with cancer related bone disease: clinical and therapeutic implications.
2007
Abstract The clinical significance of serum cathepsin K and cystatin C was assessed in patients with breast cancer (BCa) or prostate cancer (PCa) with confined disease (M0) or bone metastasis (BM). Cathepsin K and cystatin C circulating levels were determined by ELISAs in 63 cancer patients, in 35 patients with nonmalignant diseases and in 42 healthy blood donors (control group). In BCa patients, cathepsin K serum levels were significantly lower than in sex matched control group (HS; p = 0.0008) or in patients with primary osteoporosis (OP; p = 0.0009). On the contrary, cystatin C levels were significantly higher in BCa patients than in HS ( p = 0.0001) or OP ( p = 0.017). In PCa patien…