Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:3.4.23.5 (cathepsin D)
 4,130 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Elective cervical lymphadenectomy often is performed for laryngeal carcinoma to eliminate metastatic disease that escapes clinical and radiographic detection. We investigated characteristics of the primary tumor that might predict cervical lymph node status. We obtained archival tissue from 88 laryngectomies--65 with concurrent cervical lymphadenectomies. Of the 40 clinically negative necks that were dissected, 17% showed lymph node metastasis by pathologic examination. The primary tumors were examined immunohistochemically for expression of epidermal growth factor receptor (EGFR), p53, cathepsin D, proliferating cell nuclear antigen (PCNA), and Ki-67-specific antigen, and by flow cytometry for DNA ploidy-cell cycle analysis. Seventy-seven percent of the cases showed aberrant p53 staining, 99% expressed EGFR, 40% produced cathepsin D, 29% were aneuploid, and 54% had a moderate or high synthesis phase fraction (SPF). High grade, aneuploidy, and tumor vascular invasion independently predicted cervical node metastasis (p < .04 each). Supraglottic locale (p < .16) and a raggedly infiltrating invading margin (p < .13) were weakly associated with node positivity. Advanced clinical T status, the expression of EGFR, p53, and cathepsin D, the PCNA and Ki-67 indices, and SPF did not correlate with node metastasis. The presence of cervical node metastasis predicted poor disease-free (p < .005) and overall survival (p < .04). Advanced clinical T status correlated with brief overall survival (p < .02). Tumor site, histopathologic parameters, ploidy, SPF, PCNA and Ki-67 indices, and the expression of p53, EGFR, and cathepsin D did not affect survival. The presence of vascular invasion, high grade, and aneuploidy may help identify which patients would benefit from elective cervical lymphadenectomy. The correlation of cervical lymph node status and clinical T category with survival confirms the results of previous studies.
Ann Otol Rhinol Laryngol 1995 Sep
PMID:Cervical lymph node status and survival in laryngeal carcinoma: prognostic factors. 766 16

It has been shown that some types of tumour cells produce activated transforming growth factor beta-1 (TGF-beta 1). However, the mechanism for the activation of TGF-beta 1 derived from tumour cells has not been fully elucidated. The present study was undertaken to characterise an activator of latent TGF-beta 1 secreted from a human gastric cancer cell line, KATO-III. Western blot analyses using antibodies for TGF-beta 1, latency associated peptide (LAP) and latent TGF-beta 1-binding protein (LTBP) revealed that, in the cell lysate of KATO-III, TGF-beta 1 protein was expressed as a small latent complex of TGF-beta 1 and LAP. This was also confirmed by a gel chromatographic analysis of the cell lysate obtained from KATO-III. A 2.5 kb transcript of TGF-beta 1 mRNA was detected in KATO-III cells by Northern blot analysis. A gel chromatographic analysis of the conditioned medium from KATO-III cells revealed, in addition to the active form of TGF-beta 1, a factor which activated latent TGF-beta 1 from NRK-49F cells at fractions near a molecular size of 65,000. This factor was inactivated by heat (100 degrees C), acidification, trypsin and serine protease inhibitors. TGF-beta 1 activity in KATO-III cell lysate was not detected in the untreated state, but potent TGF-beta 1 activity was detected after acid treatment. These results suggest that KATO-III releases not only a latent TGF-beta 1 complex but also a type of serine protease, different from plasmin, plasminogen activator, cathepsin D, endoglycosidase F or sialidase, which activates the latent TGF-beta 1 complex as effectively as acid treatment.
Br J Cancer 1995 Sep
PMID:Identification of a transforming growth factor beta-1 activator derived from a human gastric cancer cell line. 766 80

Cathepsin D is a carboxyl protease that has been implicated as an important factor in tumor cell invasion. Sixty-nine cases of primary adenocarcinoma of the prostate were studied by the indirect immunoperoxidase method using a primary monoclonal anti-cathepsin D antibody. Immunoreactivity was graded from 0 (negative) to 4+ (intense reaction). The normal tubuloalveolar glands were, in general, negative. However, nine cases revealed focal staining of nonneoplastic luminal cells. Basal cells were negative except in areas of basal-cell hyperplasia, which were intensely positive. Thirty-nine of 78 carcinoma samples revealed 2+ or greater positive punctate lysosomal staining. In the 39 positive-stained cases, the reactivity was diffuse in three and focal in the remainder. The percentage of carcinoma cases whose worst lesions stained 2+ or greater showed a nonsignificant (P = 0.055) relation to Gleason grade but a significant (P = 0.031) relationship to pathologic stage. Thus, cathepsin D may prove to be a useful marker of prostate cancer progression.
Mod Pathol 1994 Sep
PMID:Immunohistochemical analysis of cathepsin D in prostate carcinoma. 782 8

Degradation of metallothionein (MT) from rat liver was examined. Degradation of apo-MT by liver homogenate was greater than that by cytosol. At pH 5.5, degradation by homogenate was more than that at pH 7.2. These findings suggest that proteases that function at acidic pH are probably involved in MT degradation. Because lysosomes are the principal subcellular organelles that contain acid proteases (cathepsins), we compared the degradation of apo-MT by lysosomes and cytosol. Apo-MT was degraded about 400 times faster by lysosomal fraction than by cytosolic fraction. To determine the relative importance of different cathepsins, we used different inhibitors. Leupeptin, which inhibits cathepsins B and L, inhibited the degradation of apo-MT by 80%, implying that cathepsins B and/or L might be very important in the intracellular turnover of MT. Cathepsin D appeared to be the least significant, because apo-MT degradation was reduced by about 20% by inhibiting cathepsin D. When we extended this study with purified cathepsins, we obtained the same answer, i.e., the ability of different cathepsins to degrade apo-MT was in the following order: cathepsin B >> cathepsin C > cathepsin D. While apo-MT was susceptible to degradation, ZnMT and CdMT were highly resistant to degradation. Coincubation of ZnMT or CdMT with either lysosomal extract or purified cathepsins did not result in any appreciable degradation even after 16 hr. However, longer incubations did result in some degradation, especially by purified cathepsin B. Interestingly, CdMT degraded little faster than ZnMT by both lysosomal extract as well as purified cathepsin B.(ABSTRACT TRUNCATED AT 250 WORDS)
Environ Health Perspect 1994 Sep
PMID:In vitro and in vivo studies on the degradation of metallothionein. 784 89

Human metastatic breast cancer cells in culture contain large acidic vesicles (diameter 5-10 microns) in which endocytosed extracellular matrix can be digested by activated lysosomal proteinases such as cathepsin D (P. Montcourrier et al. (1990). Cancer Res. 50, 6045-6054). We examined these large compartments by transmission electron microscopy, measured their pH by video-enhanced epifluorescence using FITC-dextran, and studied their functional significance. Their presence in metastatic MDA-MB231 cells was found to be correlated with an increased ability of cells to migrate through Matrigel and a high cathepsin D concentration. These cells were able to phagocytose 1.24 microns diameter latex beads and fluorescence Matrigel and incorporate this extracellular material into large acidic vesicles. This indicated that large acidic vesicles were associated with both phagocytosis and invasion, and are heterophagolysosomes rather than autophagosomes. Large acidic vesicles were actively acidified with a H(+)-ATPase vacuolar pump specifically inhibited by bafilomycin A1, and reached pH values (< 4), lower than the lysosomal value (pH approximately 5) in the same cells and in specialized phagocytotic cells such as macrophages. We conclude that the phagocytotic activity of breast cancer cells, associated with high cathepsin D expression, and high acidification potential, characterize cancer cells that have migrated through Matrigel.
J Cell Sci 1994 Sep
PMID:Characterization of very acidic phagosomes in breast cancer cells and their association with invasion. 784 58

A model of the barley-grain aspartic proteinase (HvAP; Hordeum vulgare aspartic proteinase) has been constructed using the rule-based comparative modelling approach encoded in the COMPOSER suite of computer programs. The model was based on the high resolution crystal structures of six highly homologous aspartic proteinases. Results suggest that the overall three-dimensional structure of HvAP (excluding the plant-specific insert; 104 residues in HvAP) is closer to human cathepsin D than other aspartic proteinases of known three-dimensional structure. Comparisons of the complexes with the substrate modelled in the active site of HvAP with those of the same substrate modelled in the active site of other aspartic proteinases of known three-dimensional structure and specificity, define residues that may influence hydrolytic specificity of the barley enzyme. We have identified residues in the S4 (Ala12), S3 (Gln13, Thr111) S2 (Ala222, Thr287, Met289), S'1 and S'3 (Ile291), S'2 and S'3 (Gln74), S'2 (Arg295), and S'3 (Pro292) pockets, that may account for the observed trends in the kinetic behaviour and specificity when compared to other aspartic proteinases. The plant-specific inserted sequence, which may play a role in the transport of HvAP to plant vacuoles (lysosomes), is similar to the saposins and is predicted to be a mixed alpha-helical and beta-strand domain.
FEBS Lett 1994 Sep 26
PMID:Comparative modelling of barley-grain aspartic proteinase: a structural rationale for observed hydrolytic specificity. 792 61

In addition to stimulation of the target gene fatty-acid synthetase, the synthetic progestin R5020 strongly inhibited estradiol-induced pS2 and cathepsin D mRNA levels in MCF7 human breast cancer cells as shown by Northern blot analysis. Inhibition was half-maximal with 30 pM R5020, and the antiprogestin RU486 had only a weak effect. Two human progesterone receptor isoforms have been described; isoform A is a truncated form of isoform B and lacks the 164 N-terminal amino acids. We hypothesized that the two isoforms could have a differential capacity to transrepress estrogen-induced responses. Therefore, in MDA-MB231 cells containing no progesterone and estrogen receptors, we transiently transfected progesterone receptor expression vectors coding for form B (hPR1 or hPR0) or form A (hPR2) along with the estrogen receptor expression vector HEO. We show that R5020 inhibited estradiol-induced transcription of the pS2-CAT reporter plasmid only in cells selectively expressing isoform B. The same results were obtained when progesterone receptor isoforms were overexpressed in MCF7, Ishikawa, HeLa, or NIH-3T3 cells. Transrepression was dependent on the promoter context since the extent of inhibition by isoform B was higher when evaluated with pS2 or cathepsin D nonpalindromic estrogen-responsive element-mediated transcription than with the perfect palindromic form of the vitellogenin gene. Isoform A was inefficient regardless of the reporter construct used. Inhibition varied with the isoform ratio, and isoform B had a dominant effect, with > 70% inhibition measured in cells transfected with the same amount of both progesterone receptor isoforms. Progestin repressed only one of the two transcription activation functions of the estrogen receptor, AF-2, which corresponds to the hormone-binding domain. We conclude that differential expression of progesterone receptor isoforms could be responsible for a tissue-specific inhibition of estrogen target genes by progestins.
J Biol Chem 1994 Sep 16
PMID:Differential effect of forms A and B of human progesterone receptor on estradiol-dependent transcription. 808

In this study, the major endosomal/lysosomal proteases cathepsin D and cathepsin B were tested on their ability to release T cell stimulatory peptides from hen egg white lysozyme (HEL) in vitro. Whereas neither enzyme could cleave unreduced HEL under mild conditions, reduced HEL was readily cleaved by cathepsin D but not by cathepsin B. Instead, cathepsin B was found to be very active in the trimming of HEL peptides after their release by cathepsin D. Following high-performance liquid chromatography (HPLC) fractionation, cathepsin D-released HEL fragments were screened for recognition by HEL-specific T cells from three strains of mice, i.e. B10.A (H-2a), C57BL/6 (H-2b) and BALB/c (H-2d). Peptides in a large number of different HPLC fractions triggered significant T cell responses in all three strains. Interestingly, the response profiles of T cells from the three different strains showed marked similarities. Also, several individual synthetic HEL sequences corresponding to selected cathepsin D-released fragments were recognized by murine T cells in the context of all three major histocompatibility complex (MHC) haplotypes tested. Our data suggest that cathepsin D rather than cathepsin B may play a central role in the initial release of HEL fragments during endosomal/lysosomal processing. The relatively long HEL fragments released by cathepsin D, containing about 20-30 amino acid residues, are significantly more promiscuous in murine class II MHC binding than the shorter synthetic HEL sequences previously employed by others for the delineation of HEL epitopes. Extensive documentation of HEL epitopes in previous investigations indicate that this promiscuity cannot be explained by simply assuming that longer peptides contain additional epitopes. Rather, an increased peptide length by itself appears to promote promiscuous MHC binding.
Eur J Immunol 1994 Sep
PMID:Cathepsin D, but not cathepsin B, releases T cell stimulatory fragments from lysozyme that are functional in the context of multiple murine class II MHC molecules. 808 34

Cathepsins D, B, and L are acidic lysosomal proteinases involved in intracellular protein turnover. Increased levels of these enzymes have been reported to be indicators of aggressive tumor behavior in human and rodent tumors. In breast cancer increased levels of cathepsin D have been reported to be an independent prognostic factor in women with stage I disease. We used standard immunohistochemical techniques on formalin-fixed, paraffin-embedded tissue to examine the levels of cathepsins D, B, and L in 80 carcinomas of the breast and compared that with other indicators of aggressive tumor behavior, including stage of disease, tumor size, nuclear grade, estrogen receptor status, disease recurrence, and 5-year survival rates. Positive granular cytoplasmic staining was detected for cathepsin D in 90% of the tumors, for cathepsin B in two thirds of the tumors, and for cathepsin L in approximately one half of the tumors. Positive staining also was seen in normal breast epithelium, areas of apocrine metaplasia, stromal fibroblasts, and macrophages. Our results did not show a correlation between the expression of cathepsins D, B, and L and other indicators of aggressive tumor behavior. We conclude that the results obtained using polyclonal anticathepsin antibodies do not support the prognostic usefulness of immunohistochemical analysis of these three proteinases in tumor cells in human breast cancer.
Hum Pathol 1994 Sep
PMID:Immunohistochemical analysis of cathepsins D, B, and L in human breast cancer. 808 57

High cathepsin D (cath-D) concentration in breast cancer cytosol is associated with increased risk of metastasis. To specify the relative contribution of the different cells types responsible for cath-D level in cytosol, we validated semiquantitative cath-D immunoperoxidase staining on formalin-fixed, paraffin-embedded sections, using the M1G8 monoclonal antibody, one of the two antibodies of the cytosolic assay. Using computer-aided image analysis, cath-D level in cancer cells was estimated by integrating both staining intensity in each cell and proportion of stained cells. We confirmed on 41 primary breast cancers a higher expression of cath-D in cancer cells compared with peritumoral mammary glands. Cancer cell staining was mostly in lysosomes and for some invasive ductal carcinomas in large vesicles corresponding to phagosomes. Lymphocytes and fibroblasts were not or were only weakly stained. Macrophages also were stained for cath-D, generally on the periphery of the tumor area. The cytosolic cath-D level was correlated with cath-D expression in cancer cells (r = .76; P = 1 x 10(-4)) rather than with the number of macrophages in the tumor (r = .29; P = .09), as determined by use of the specific anti-CD68 antibody. There was a significant increase in the tissue cath-D level in tumors containing large vesicles compared with tumors without large vesicles. This approach provides a means to separately estimate the prognostic significance of cath-D expression in cancer cells and macrophages when evaluating risk of metastasis.
Hum Pathol 1994 Sep
PMID:Cathepsin D immunostaining in paraffin-embedded breast cancer cells and macrophages: correlation with cytosolic assay. 808 57


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