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)

Among the various factors reported as having significant prognostic value in primary breast cancers, the author discusses the value of well established "classical" prognostic factors used routinely and "new" prognostic factors developed over recent years as a result of progress in cell and molecular biology. The presence of axillary lymph node metastases remains the most important prognostic factor of recurrence, justifying post-surgical adjuvant therapy. However, in patients with negative axillary nodes (N-), the size of the tumour, Scarff-Bloom-Richardson (SBR and MSBR) histological grade, certain particular histological types (carcinoma in situ and tubular, colloid or pure papillary cancer) and hormone receptors (ER and PR) appear to be well established prognostic factors allowing the identification, within this group of N- patients who generally have a good prognosis, those patients with a low risk of recurrence and therefore not requiring adjuvant therapy. In contrast, the proliferative activity (ploidy and S phase, Thymidine Labeling Index, antibody Ki67), cathepsin D, thymidine kinase, EGF receptors, several genes including oncogene HER-2/neu, are recently developed prognostic factors whose significance needs to be confirmed by further studies.
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PMID:[Prognostic factors in breast cancer]. 134 Jan 64

In the natural history of post-menopausal patients with primary breast cancer, high estrogen receptor levels (ER) have been associated with a poor recurrence-free survival. The purpose of this study was to investigate whether there are any biological intratumoral characteristics to support this puzzling clinical observation. In a population of 542 post-menopausal, primary-breast-cancer patients, 3 normal distributions fitted into the frequency distribution curve of the logarithmically transformed ER-EIA values. The biological profiles of the low ER group, and of the intermediate and high ER groups identified in the ER-positive population were compared. Parameters correlated with ER functional aspect (progesterone receptors and PS2), receptors of epidermal growth factor (EGFR), protease cathepsin D and tumor proliferation (deduced from thymidine kinase activity) were analyzed. As previously reported, the levels of progesterone receptors and PS2 increased significantly from the low to the high ER groups. The highest levels of cathepsin D and thymidine kinase which have been previously related to a poor prognosis in breast cancer were found in the low ER group, but high levels were, surprisingly, also found in the high ER group. This study indicates that the ER-positive post-menopausal population is biologically heterogeneous. The high levels of thymidine kinase found in the high ER group suggest that overexpression of ER may be associated with proliferation enhancement, partly explaining the poor spontaneous prognosis related to this subset.
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PMID:Biological heterogeneity of ER-positive breast cancers in the post-menopausal population. 792 97

Cathepsin D, a lysosomal proteinase, is induced by estrogens in mammary cancer cells where its concentration is correlated with a higher risk of metastasis. Its gene expression is stimulated by estrogens in MCF7 cells, and we have shown that a short proximal promoter fragment from -365 to -122 is required for this induction. We now characterize, at -261, a nonconsensus estrogen-responsive element (ERE) (E2) with two differences in the distal half of its palindrome, which confers estradiol responsiveness to the heterologous Herpes simplex virus thymidine kinase promoter in transient transfection experiments. This ERE is located in a 21-base pair sequence: 5'GGGCCGGGCTGACCCCGC GGG3', containing a GC-rich region in its 3'-part, which is almost perfectly repeated at -362 (the E1 site). The E2 site was necessary but not sufficient to mediate an estrogen response and required cooperation with the homologous E1 element and/or with general transcription sites located downstream. In vitro, the E2 site but not the E1 site was protected by estrogen receptor (ER) against DNAse I digestion, and gel shift experiments suggested an interaction with the ER as a dimer. Moreover, we showed in vivo that ER DNA binding domain was required to mediate estrogen induction from the cathepsin D ERE. We conclude that estradiol induction of cathepsin D is mediated by interaction of the ER with a nonconsensus ERE that requires synergy with other elements located upstream and/or downstream of this central ERE.
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PMID:Characterization of the proximal estrogen-responsive element of human cathepsin D gene. 793 85

Cathepsin D is an estrogen (17 beta-estradiol, E2)-inducible lysosomal protease. A putative estrogen receptor (ER)-Sp1-like sequence (GGGCGG(n)23ACGGG) has been identified in the non-coding strand of the cathepsin D promoter (-199 to -165), and electromobility shift assays of nuclear extracts from MCF-7 and HeLa cells confirm that both the ER and Sp1 protein bind to 32P-labeled ER/Sp1 oligo. For example, nuclear extracts from MCF-7 cells bind to the 32P-labeled ER/Sp1 oligo; however, ER/Sp1 binding can be decreased by selective competition with excess unlabeled estrogen responsive element and Sp1 oligos, immunodepletion with ER or Sp1 antibodies, and by treating cells with ICI 164,384, an antiestrogen which inhibits formation of ER homodimer. Moreover, E2-induced chloramphenicol acetyltransferase (CAT) activity in MCF-7 cells cotransfected with a human estrogen receptor expression plasmid and a plasmid containing an ER/Sp1 sequence cloned upstream to a thymidine kinase promoter and a CAT reporter. In cotreatment studies, ICI 164,384 inhibited E2-induced CAT activity. In contrast, E2 did not induce CAT activity in MCF-7 cells transfected with plasmids containing mutations in the ER or Sp1 segments of the ER/Sp1 oligo, thus confirming that both cognate binding sites are required for estrogen responsiveness.
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PMID:Estrogen receptor-Sp1 complexes mediate estrogen-induced cathepsin D gene expression in MCF-7 human breast cancer cells. 819 46

The flanking sequences of several genes have been shown to direct a position independent expression of transgenes. Attempts to completely identify the insulating sequences have failed so far. Some of these sequences contain a matrix attached region (MAR) located in the flanking part of the genes. This article will show that the MARs in cultured cells located in the 3' OH region of the human apolipoprotein B100 (Apo B100) and within the SV40 genome were unable to stimulate and insultate transgene expression directed by the promoters from a rabbit whey acidic protein (WAP) gene or from human cytomegalovirus (hCMV) early genes. In transgenic mice, the MAR from the Apo B100 and SV40 genes did not enhance the expression of a transgene containing the rabbit whey acid protein (WAP) promotor, the late gene SV40 intron (VP1 intron), the bovine growth hormone (bGH) cDNA and the SV40 late gene terminator. This construct was even toxic for embryos. Similarly, the specialized chromatin structure (SCS) from the Drosophila 87A7 HSP70 gene reduced chloramphenicol acetyl transferase (CAT) activity when added between a cytomegalovirus (CMV) enhancer and a Herpes simplex thymidine kinase (TK) gene promoter. This inhibitory action was almost complete when a second SCS sequence was added before the CMV enhancer. Sequences from the firefly luciferase and from the human gene cathepsin D cDNA used as control unexpectedly showed a similar inhibitory effect when added to the CMVTKCAT construct instead of SCS. When added before the CMV enhancer and after the transcription terminator in the CMVTKCAT construct, the SCS sequence was unable to insulate the integrated gene as seen by the fact that the level of CAT in cell extracts were by no means correlated with the number of copies in individual clones. From these data, it is concluded that i) a MAR containing the canonical AT rich sequences does not amplify the expression of all gene constructs ii) At rich MAR sequences do not have per se an insulating effect iii) Drosophila SCS from the 87A7 HSP70 gene has no insulating effect in all gene constructs (at least in mammalian cells) iv) and the addition of a DNA fragment between an enhancer and a promoter in a gene construct cannot be used as a reliable test to evaluate its insulating property.
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PMID:The effect of matrix attached regions (MAR) and specialized chromatin structure (SCS) on the expression of gene constructs in cultured cells and in transgenic mice. 885 71

We assayed thymidine kinase (TK) and cathepsin D (Cath-D) in 200 breast carcinomas and we found that they were significantly correlated. This correlation was present in lymph node positive tumours, in G2 and G3, in T1 and in invasive ductal carcinomas. In addition, TK and Cath-D did not correlate with oestrogen receptor (ER) and progesterone receptor (PgR) status. We conclude that the relationship between Cath-D and TK may indicate a tumour population of high proliferation activity and invasiveness potential, related to a more aggressive phenotype, whose identification may be useful in defining prognosis.
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PMID:Co-expression of thymidine kinase and cathepsin D in 200 primary breast carcinomas. 1109 79