This study aimed to explore the molecular mechanism of rubioncolin C(RuC) in inhibiting gastric cancer(GC). AGS and MGC803 cell lines were selected as cellular models. After treating the cells with RuC at different concentrations, the effects of RuC on the proliferation ability of GC cells were assessed using the CCK-8 method, real-time cellular analysis(RTCA), and colony formation assays. Transmission electron microscopy was used to observe subcellular structural changes. Immunofluorescence was applied to detect LC3 fluorescent foci. Acridine orange staining was used to evaluate the state of intracellular lysosomes. Western blot was employed to detect the expression of autophagy-related proteins LC3Ⅱ, P62, and lysosomal cathepsin D(CTSD). The SuperPred online tool was used to predict the target proteins that bound to RuC, and molecular docking analysis was conducted to identify the interaction sites between RuC and CTSD. The drug affinity responsive target stability(DARTS) assay was performed to detect the direct binding interaction between RuC and CTSD. The results showed that RuC significantly inhibited the proliferation and colony formation of GC cells at low concentrations, with 24-hour half-maximal inhibitory concentrations(IC_(50)) of 3.422 and 2.697 μmol·L~(-1) for AGS and MGC803 cells, respectively. After 24 hours of treatment with RuC at concentrations of 1, 2, and 3 μmol·L~(-1), the colony formation rates for AGS cells were 61.0%±1.5%, 28.0%±0.5%, and 18.2%±0.5%, respectively, while the rates for MGC803 cells were 56.0%±0.5%, 23.3%±1.0%, and 11.8%±1.0%, all of which were significantly reduced. Transmission electron microscopy revealed that RuC promoted an increase in autophagosome formation in GC cells. Immunofluorescence detection showed that LC3 fluorescent foci of GC cells increased with the increase in RuC dose. RuC up-regulated the expression of autophagy-related proteins LC3Ⅱ and P62 in GC cells. Acridine orange staining indicated that RuC altered the acidic environment of lysosomes. SuperPred online prediction identified CTSD as a potential target protein of RuC. Western blot analysis revealed that RuC induced the up-regulation of the inactive precursor of CTSD in GC cells. CTSD activity assays indicated that RuC reduced the activity of CTSD. Molecular docking simulations found that RuC bound to the substrate-binding region of CTSD, forming hydrogen bonds with the Tyr205 and Asp231 residues. Microscale thermophoresis and DARTS assays further confirmed that RuC directly bound to CTSD. In summary, RuC inhibits lysosomal activity by targeting and down-regulating the expression of CTSD, thereby inducing autophagosome accumulation in GC cells.
Humans ; Stomach Neoplasms/enzymology* ; Cathepsin D/chemistry* ; Cell Line, Tumor ; Molecular Docking Simulation ; Cell Proliferation/drug effects* ; Autophagosomes/metabolism* ; Autophagy/drug effects*

Cathepsin D (CatD, EC 3.4.23.5) is a member belonging to the subfamily of aspartic endopeptidases, which are classified into the MEROPS clan AA, family A1. Helminth parasites express a large set of different peptidases that play pivotal roles in parasite biology and pathophysiology. However, CatD is less well known than the other classes of peptidases in terms of biochemical properties and biological functions. In this study, we identified 2 novel CatDs (CsCatD1 and CsCatD2) of Clonorchis sinensis and partially characterized their properties. Both CsCatDs represent typical enzymes sharing amino acid residues and motifs that are tightly conserved in the CatD superfamily of proteins. Both CsCatDs showed similar patterns of expression in different developmental stages of C. sinensis, but CsCatD2 was also expressed in metacercariae. CsCatD2 was mainly expressed in the intestines and eggs of C. sinensis. Sera obtained from rats experimentally infected with C. sinensis reacted with recombinant CsCatD2 beginning 2 weeks after infection and the antibody titers were gradually increased by maturation of the parasite. Structural analysis of CsCatD2 revealed a bilobed enzyme structure consisting of 2 antiparallel β-sheet domains packed against each other forming a homodimeric structure. These results suggested a plausible biological role of CsCatD2 in the nutrition and reproduction of parasite and its potential utility as a serodiagnostic antigen in clonorchiasis.
Animals ; Aspartic Acid Endopeptidases ; Biology ; Cathepsin D ; Cathepsins ; Clonorchiasis ; Clonorchis sinensis ; Eggs ; Helminths ; Humans ; Intestines ; Metacercariae ; Ovum ; Parasites ; Peptide Hydrolases ; Rats ; Reproduction

BACKGROUND/AIMS: A single gene mutation alone cannot explain the poor prognosis of colorectal cancer. This study aimed to establish a correlation between the expression of six proteins and the prognosis of colorectal cancer patients. METHODS: Tissue samples were collected from 266 patients who underwent surgery for colorectal cancer at our institution from January 2006 to December 2007. The expression of six proteins were determined using immunohistochemical staining of specimens. RESULTS: Cathepsin D, p53, COX-2, epidermal growth factor receptor, c-erbB-2, and Ki-67 expression were detected in 38.7%, 60.9%, 37.6%, 35.7%, 30.1%, and 74.4% of the samples, respectively. The expression of cathepsin D was significantly correlated with reduced cancer-free survival (p=0.036) and colorectal cancer-specific survival (p=0.003), but the other expression levels were not. In a multivariate analysis, cathepsin D expression was found to be an independent prognostic factor for poorer colorectal cancer-specific survival (hazard ratio, 8.55; 95% confidence interval, 1.07 to 68.49). Furthermore, patients with tumors expressing four or more of the proteins had a significantly decreased cancer-free survival rate (p=0.006) and colorectal cancer-specific survival rate (p=0.002). CONCLUSIONS: Patients with cathepsin D positivity had a poorer outcome than patients who were cathepsin D-negative. Thus, cathepsin D may provide an indicator for appropriate intensive follow-up and adjuvant chemotherapy.
Adenocarcinoma/*pathology ; Adenocarcinoma, Mucinous/pathology ; Adult ; Aged ; Cathepsin D/analysis ; Colorectal Neoplasms/*pathology ; Cyclooxygenase 2/analysis ; Female ; Humans ; Ki-67 Antigen/analysis ; Male ; Middle Aged ; Prognosis ; Receptor, Epidermal Growth Factor/analysis ; Receptor, ErbB-2/analysis ; Survival Analysis ; Tumor Markers, Biological/*analysis ; Tumor Suppressor Protein p53/analysis

OBJECTIVEAutophagy is involved in several neurodegenerative diseases and recently its role in acute brain injury has won increasing interest. Spinal cord injuries (SCIs) often lead to permanent neurological deficit. Therefore, in this study, we examined the pro?les of autophagy-linked proteins (MAP-LC3) after SCI to investigate whether the expression of autophagy contributes to neurological deficit after SCI.

METHODSAdult female Sprague-Dawley rats were used and randomly divided into control and SCI groups. All the rates received laminectomy at T8-T10 level. Those in the SCI group received additional exposure of the dorsal surface of the spinal cord, followed by a weight- drop injury. Thereafter we investigated the expression levels of MAP-LC3, beclin-1, Cathepsin D and the beclin-1-binding protein bcl-2 by western blot analysis at 12 h, 24 h, 3 d, 7 d, 21 d and 28 d. One-way ANOVA with Tukey post hoc test was used to compare data between groups.

RESULTSWe observed significant increase in the level of LC3 (LC3-II/LC3-I) at 3 d and 7 d after SCI when compared with the sham group. While the level of beclin-1 and ratio of beclin-1/bcl-2 was found to have increased from 12 h to 24 h after injury. Cathepsin D expression was also elevated at 7 d (P<0.01).

CONCLUSIONBased on the above mentioned data, we proposed that autophagy plays a role in the manifestation of cell injury following SCI.

Adaptor Proteins, Signal Transducing ; metabolism ; Animals ; Apoptosis Regulatory Proteins ; metabolism ; Autophagy ; physiology ; Beclin-1 ; Blotting, Western ; Cathepsin D ; metabolism ; Disease Models, Animal ; Female ; Laminectomy ; Microtubule-Associated Proteins ; metabolism ; Rats ; Rats, Sprague-Dawley ; Spinal Cord Injuries ; metabolism

BACKGROUND: To investigate the molecular basis for invasion of malignant gliomas, proteomic analysis approach was carried out using two human glioma cell lines, U87MG and U343MG-A that demonstrate different motility and invasiveness in in vitro experiments. METHODS: High-resolution two-dimensional gel electrophoresis and matrix-assisted laser-desorption/ionization time-of-flight mass spectrometry analysis were performed. RESULTS: Nine distinct protein spots that were recognized with significant alteration between the two cell lines. Five of these protein spots were up-regulated in U87MG and four were up-regulated in U343MG-A. CONCLUSION: Among these proteins, cathepsin D was shown to be one of the important proteins which are related with glioma invasion. However, further studies are necessary to reveal the exact role and mechanism of cathepsin D in glioma invasion.
Cathepsin D ; Cell Line* ; Electrophoresis, Gel, Two-Dimensional ; Glioma* ; Humans ; Mass Spectrometry ; Proteomics

PURPOSE: Leukemic promyelocytes have the unique ability to undergo differentiation after exposure to retinoic acid and both differentiation and apoptosis after exposure to arsenic trioxide (ATO). Recent studies have shown that inhibition of Src family kinases (SFKs) resulted in enhancement of retinoic acid-induced myeloid differentiation. MATERIALS AND METHODS: In this study, we investigated the question of whether the SFK inhibitor PP2 enhanced the differentiation of NB4 cells when combined with ATO as well as when combined with all-trans-retinoic acid (ATRA). In addition, we attempted to determine the difference in retinoic acid-induced gene expression between cells treated with PP2 in combination with ATRA and in combination with ATO. RESULTS: SFK inhibitor PP2 induced significant enhancement of ATRA- or ATO-induced differentiation of NB4 cells. A significantly stronger synergistic effect was observed when PP2 was combined with ATRA than when combined with ATO. Flow cytometric analysis demonstrated a significant increase in CD11b-positive granulocytes up to 60.73% and 31.58%, respectively. These results were confirmed by nitroblue tetrazolium staining. These effects were not related to apoptosis. Results of Annexin-V-fluorescein staining revealed that PP2 combined with ATRA or PP2 combined with ATO did not induce apoptosis in NB4 cells. Retinoic acid-induced gene expression was different in both groups. Intercellular adhesion molecule-1 expression showed a significant increase in cells treated with PP2 in combination with ATRA, whereas cathepsin D expression showed a significant increase in cells treated with PP2 in combination with ATO. CONCLUSION: Our data showed that SFK inhibitor PP2 enhanced acute promyelocytic leukemia cell differentiation when combined with either ATRA or ATO with difference in activation of retinoic acid-induced genes.
Apoptosis ; Arsenic ; Arsenicals ; Cathepsin D ; Cell Differentiation ; Cell Line ; Gene Expression ; Granulocyte Precursor Cells ; Granulocytes ; Humans ; Intercellular Adhesion Molecule-1 ; Leukemia, Promyelocytic, Acute ; Nitroblue Tetrazolium ; Oxides ; Phosphotransferases ; Pyrimidines ; src-Family Kinases ; Tretinoin

Osteoporosis is a common senile disease that results in fragility fractures. With an ageing population, the medical and socioeconomic effect of osteoporosis, particularly postmenopausal osteoporosis, will increase further. Currently, good anti-fracture data supports many available anti-resorptive and anabolic drugs including bisphosphonates, selective estrogen receptor modulators, and recombinant human parathyroid hormones. Calcium and vitamin D are also essential treatments for the prevention and treatment of osteoporosis. Although, bisphosphonate is the cornerstone of osteoporosis treatment and is considered as the first line of therapy, their duration of therapy and long-term safety is under question. Novel agents, particularly denosumab, inhibitors of cathepsin K, andanabolic agents that act on Wnt signaling, will increase the therapeutic options for clinicians in the coming years.
Antibodies, Monoclonal, Humanized ; Calcium ; Cathepsin K ; Diphosphonates ; Female ; Humans ; Osteoporosis ; Osteoporosis, Postmenopausal ; Selective Estrogen Receptor Modulators ; Vitamin D ; Denosumab

OBJECTIVETo explore the Zedoary oil on A549 cell line of collagen deposition cat D and cat K expression.

METHODThe A549 cell line were treat by Zedoary oil on four different concentrations (0, 40, 80, 120 mg x L(-1)) in different time. Dynamic changes of collagen in A549 cell using Picric-sirius red method. Cat D and Cat K expression of level were detected by using western blot.

RESULTThe collagen content showed that Zedoary oil had an inhibitory effect on the deposition of A549 cells. The results of western blot showed that the expression of cat D and cat K were up-regulated significangly in A549 cells of Zedoary oil groups compared with that in controls.

CONCLUSIONA549 cell of collagen deposition were reduced by Zedoary oil. The effects may due to the up-regulation of cat D and cat K.

Animals ; Blotting, Western ; Cathepsin D ; metabolism ; Cathepsin K ; metabolism ; Cell Line, Tumor ; Collagen ; metabolism ; Curcuma ; chemistry ; Gene Expression Regulation, Neoplastic ; drug effects ; Plant Oils ; isolation & purification ; pharmacology ; Up-Regulation

OBJECTIVE: To study the function of lymphangiogenesis and the expression of Cathepsin D (Cath-D) in laryngeal carcinoma metabasis and clinical pathology character. METHOD: The expression of Cath-D were detected in 76 laryngeal carcinoma with immunohistochemistry (SP method). Podoplanin was used as the marker of lympgatic vessel endotheliocytes to label lympgatic vessel in 76 laryngeal carcinoma,lymphatic microvessel density were measured,and the paraneoplastic tissues was used as control group. RESULT: The positive rate of Cath-D in paraneoplastic tissue, laryngeal carcinoma and in pathology classification, in clinical stage, in cervicale lymphonode metastasis negative and positive group were significantly different. However, there had no difference between the positive rate of Cath-D in the age specific and clinical classification. c) The lymphatic microvessel density in paraneoplastic tissue, laryngeal carcinoma and clinical stage, in glottic carcinoma and supraglottic carcinoma, in cervical lymphonode metastasis negative and positive group were significantly different; but there had no difference in age-specific and pathology classification. CONCLUSION (1) The high expression of lymphatic microvessel density and the increasing expression of Cath-D could promote cervical lymphonode metastasis in aryngeal carcinoma. (2) There had a correlation between the high expression of lymphangiogenesis and Cath-D in laryngeal carcinoma, and had cooperation in aryngeal carcinoma lymphonode metastasis.
Biomarkers, Tumor ; metabolism ; Carcinoma ; metabolism ; pathology ; physiopathology ; Cathepsin D ; metabolism ; Female ; Glottis ; Humans ; Immunohistochemistry ; Laryngeal Neoplasms ; metabolism ; pathology ; physiopathology ; Lymphangiogenesis ; physiology ; Lymphatic Metastasis ; Lymphatic Vessels ; metabolism ; Male ; Membrane Glycoproteins ; metabolism

Cathepisn D plays a key role in early process of apoptosis before mitochondrion damage and caspases activations, and also involves in Alzheimer's disease (AD). Glycosaminoglycans (GAGs) have been suggested to inhibit the progress of apoptosis. Fucoidan, a nature GAGs mimetic, is shown as a potential candidate for neuroregressive disease. Here we reported PC12 cells response to oxidative stress with clear cathepsin D release, followed by caspase-3 activation. We found that fucoidan treatment can alleviate cathepsin D and caspase-3 activation, and improve cell survival. Furthermore, for the first time, fucoidan was shown to directly inhibit human liver cathepsin D by a dose-dependent way. These results support that cathepsin D involves in early apoptosis, suggest that fucoidan can decrease apoptosis at lysosome-cathepsin D level, which opens a new therapeutic approach to AD.
Alzheimer Disease ; drug therapy ; metabolism ; Animals ; Apoptosis ; drug effects ; Caspase 3 ; metabolism ; Caspase Inhibitors ; Cathepsin D ; antagonists & inhibitors ; metabolism ; Cell Line, Tumor ; Cell Survival ; drug effects ; Humans ; Hydrogen Peroxide ; metabolism ; Oxidative Stress ; drug effects ; PC12 Cells ; Polysaccharides ; pharmacology ; Rats