Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0006142 (breast cancer)
 160,383 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The expression of the aberrant N-acetylgalactosamine (GalNAc) glycoconjugates, detected by binding of the lectin from Helix pomatia (HPA) is reported to be associated with metastatic competence and poor prognosis in a range of human adenocarcinomas, but the functional significance of the glycoconjugates in metastatic mechanisms is unknown. We have employed seven cell lines derived from normal breast epithelium, primary breast cancer and breast cancer metastases which stably express varying levels of HPA-binding glycoconjugates consistent with their derivation and phenotype. These cell lines have been thoroughly characterised and express identical profiles of HPA-binding glycoconjugates as tumour cells derived from clinical samples. Their ability to adhere to, and invade through, basement membrane components was investigated in a matrigel assay system, and the functional role of the aberrant GalNAc glycans assessed by competitive inhibition experiments using HPA. The behaviour of the cell lines in these assay systems was entirely consistent with their derivation and phenotype, but there was no evidence that the glycoconjugates of interest were functionally involved in adhesion or invasion mechanisms. Research in our laboratory is ongoing to seek a functional role for the HPA-binding glycoconjugates in other aspects of the metastatic cascade.
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PMID:Investigations into the potential role of aberrant N-acetylgalactosamine glycans in tumour cell interactions with basement membrane components. 1240 85

The membrane epithelial mucin MUC1 is expressed at the luminal surface of most simple epithelial cells, but expression is greatly increased at lactation and in most breast carcinomas. The increase in level of expression of MUC1 in breast cancer is accompanied by changes in the profile of glycosyl transferases involved in the synthesis of the O-glycans attached to the MUC1 core protein. The cancer-associated mucin is therefore structurally different from the normal mucin, and expresses novel B cell epitopes. MUC1 antibodies are used for in vivo targeting of breast and ovarian tumors, and there is considerable interest in MUC1 as a possible target antigen for the immunotherapy of breast cancer. The different glycoforms can affect cell interactions differently, depending on whether specific interactions with lectins occur. In the absence of such lectin interactions, the long sialylated and negatively charged molecule can inhibit intercellular interactions between other cell surface molecules. The potential role of the different components of the immune system in MUC1 responses are discussed within the framework of how to develop logical strategies for designing clinical studies.
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PMID:MUC1 and the immunobiology of cancer. 1246 41

Our previous studies showed that expression of the GalNAcbeta1-->4GlcNAc group on N-linked oligosaccharides is associated with functional differentiation of the bovine mammary gland. In the present study, the occurrence of the GalNAcbeta1-->4GlcNAc group was established in human milk proteins and membrane glycoproteins from a human breast cancer cell line, MRK-nu-1, by structural analysis of oligosaccharides released by hydrazinolysis. Whether the expression level of the disaccharide group is affected upon malignant transformation was examined in human breast cancer specimens using Wistaria floribunda agglutinin (WFA) which interacts with oligosaccharides with N-acetylgalactosamine at their termini. Lectin blot analysis of membrane glycoprotein samples from human breast cancer specimens showed that the number of protein bands reacting with WFA, as well as their intensities, are lower in samples from primary carcinoma lesions compared with samples from surrounding normal tissues. No lectin binding was observed when the blots were treated with jack bean beta-N-acetylhexosaminidase or N-glycanase, indicating that WFA-reactive oligosaccharides are N-linked. A histochemical study of tissue specimens from 92 patients with breast cancer revealed that the reduced WFA staining levels in primary carcinoma lesions correlate with advancing clinical stages and prognostic status (i.e., 58% of patients in a group showing reduced/negative staining died of disease recurrence, whereas more than 90% of those in the positive staining group survived for 5 years after surgery). These results indicate that reduced expression of beta-N-acetylgalactosaminylated N-linked oligosaccharides on primary carcinoma lesions predicts a poor prognosis for patients with breast cancer.
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PMID:Prognostic significance of reduced expression of beta-N-acetylgalactosaminylated N-linked oligosaccharides in human breast cancer. 1271 46

Because of the probable involvement of cholinesterases (ChEs) in tumorigenesis, this research was addressed to ascertaining whether breast cancer metastasis alters the content of acetylcholinesterase (AChE) and/or butyrylcholinesterase (BuChE) in axillary lymph nodes (LN). ChE activity was assayed in nine normal (NLN) and seven metastasis-bearing nodes (MLN) from women. AChE and BuChE forms were characterised by sedimentation analyses, hydrophobic chromatography and western blotting. The origin of ChEs in LN was studied by lectin interaction. AChE activity dropped from 21.6 mU/mg (nmol of the substrate hydrolysed per minute and per milligram protein) in NLN to 3.8 mU/mg in MLN (p < 0.001), while BuChE activity (3.6 mU/mg) was little affected. NLN contained globular amphiphilic AChE dimers (G2A, 35%), monomers (G1A, 30%), hydrophilic tetramers (G4H, 8%), and asymmetric species (A4, 23%, and A8, 4%); MLN displayed only G2A (65%) and G1A (35%) AChE forms. NLN and MLN contained G4H (79%), G4A (7%), and G1H (14%) BuChE components. Neither the binding of ChE forms with lectins and antibodies nor the subunit size were altered by metastasis. The higher level of AChE in NLN than in brain and the specific pattern of AChE forms in NLN support its role in immunity. The different profile of AChE forms in NLN and MLN may be useful for diagnosis.
Breast Cancer Res Treat 2003 Jul
PMID:Breast cancer metastasis alters acetylcholinesterase activity and the composition of enzyme forms in axillary lymph nodes. 1288 4

The in vitro antiproliferative or stimulatory activity of an aqueous mistletoe extract (AME) with a defined content of bioactive mistletoe lectin (ML) was investigated in 6 human tumor cell lines, including two melanomas and leiomyosarcomas, each of which had previously been reported to show evidence of growth stimulation if treated with low concentrations of isolated ML. The effects of AME were compared to that of the standard cytotoxic agent adriamycin (ADR) using the well established propidium iodide and sulforhodamin B proliferation assays. The AME concentrations used ranged from 0.5 pg to 5 ng (0.82 fMol-85 pM) bioactive ML/ml in melanoma (HT-144, SK-MEL-28) and leiomyosarcoma (SK-MLS-1, S-UT-1B) cell lines and from 0.1-100 ng ML/ml (1.7 pM-1.7 nM) in MCF-7 breast cancer and SW620 colon carcinoma cell lines, respectively. The influence of AME on cell growth was determined at various time-points from 24 hours to 6 days of exposure. We found a time- and cell line-dependent inhibition of tumor cell growth, but no reproducible stimulation of tumor cell proliferation. Inhibitory concentrations 50% (IC50) for e.g. the SK-MEL-28 melanoma cell line, decreased from 4.1 ng ML/ml at 24 hours to 0.16 ng ML/ml at 72 hours and 0.18 ng ML/ml at 5 days. Our data clearly demonstrate that, by applying scientifically valid methods and procedures, the standardized AME did not stimulate tumor cell proliferation but showed time- and concentration-dependent antiproliferative effects.
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PMID:No evidence of stimulation of human tumor cell proliferation by a standardized aqueous mistletoe extract in vitro. 1466 80

This epidemiological study was performed to evaluate the influence of postoperative complementary treatment with lectin-standardized mistletoe extract (sME) on breast cancer patients. The design (retrolective cohort analysis with parallel groups) and conduct of the study were in agreement with current standards for prospectively randomized clinical trials. A cohort of 1,248 breast cancer patients on postoperative chemo-, radio-, hormone-therapy were studied in 27 randomized centers. Patients with complementary medications other than sME were excluded from the evaluation and the final analysis was performed on data of 689 patients. From this cohort 219 patients received a complementary treatment exclusively with sME (therapy group), while 470 patients were without complementary treatment (control group). The median follow-up time was 284 days (therapy group) and 285 days (control group). The primary end-point of the study was to determine the impact of complementary sME treatment on disease- or therapy-induced adverse reactions in breast cancer patients. Imbalances for causal effects (covariates) were adjusted by propensity scores. Final evaluation was performed by estimating the linear regression between change in symptom score and propensity score with all data and using the regression line to calculate the change in symptom score expected for each patient. Tumor-associated events were evaluated by number and time until event. The safety of sME treatment was analysed in terms of number, severity, duration and outcome of adverse reactions. As compared to breast cancer patients without complementary treatment (control group), the administration of sME (therapy group) resulted in a significant reduction of adverse reactions induced by the tumor-destructive therapies (e.g. nausea, gastro-intestinal tract symptoms, depression, fatigue, mental symptoms) and prolonged relapse-free intervals, most pronounced for UICC stages IIa and IIb. The rate of sME-associated adverse reactions was 12.8%. All side-effects were mild to moderate, predominantly local skin reactions and self-limiting without therapeutic intervention. Complementary treatment of breast cancer patients with lectin-standardized mistletoe extract (sME) proved to be a well tolerated optimization of standard tumor-destructive therapies, mainly improving quality of life and relapse-free intervals in defined UICC stages.
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PMID:Influence of postoperative complementary treatment with lectin-standardized mistletoe extract on breast cancer patients. A controlled epidemiological multicentric retrolective cohort study. 1498 70

Patients with breast cancer receiving adjuvant chemotherapy frequently suffer from a restricted quality of life (QoL) due to the side-effects of chemotherapy and the consequences of coping with the diagnosis. Therefore, the objective of this clinical study was to investigate the impact of PS76A2, an aqueous mistletoe extract standardised to the galactoside-specific mistletoe lectin, on QoL by performing a placebo-controlled trial. Overall, 272 patients with breast cancer receiving adjuvant CMF chemotherapy (cyclophosphamide-methotrexate-fluorouracil) were enrolled and randomised to groups receiving placebo or PS76A2 at concentrations of 10, 30 or 70 ng mistletoe lectin (ML) per ml. The patients received 0.5 ml study medication twice weekly subcutaneously for 15 consecutive weeks (4 CMF cycles). Primary variables were the self-assessment QoL scores GLQ-8 (Global Life Quality) and Spitzer's uniscale. As a result, statistically significant effects on QoL were obtained with the medium dose (15 ng ML/0.5 ml). The treatment difference between the medium dose and placebo with regard to the GLQ-8 sum was 60.8 mm (95% confidence interval: 19.3 to 102.0 mm). The treatment effect for Spitzer's uniscale between the medium dose and placebo was 16.4 mm (95% confidence interval: 6.3 to 26.6 mm). The results on QoL were supported by an increase of T helper lymphocytes (CD4+) and the CD4+/CD8+ ratio (p<0.05). Overall, PS76A2 was well tolerated. Local reactions at the injection sites occurred dose-dependently, but were mild at the low and medium dose levels.
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PMID:The standardised mistletoe extract PS76A2 improves QoL in patients with breast cancer receiving adjuvant CMF chemotherapy: a randomised, placebo-controlled, double-blind, multicentre clinical trial. 1515 63

The mushroom Paecilomyces japonica, grown on the silkworm larvae, has been used in Asia as a nutraceutical, tea, and Chinese medicine. In the present study, a sialic acid-specific lectin has been purified from the mushroom P. japonica using affinity chromatography on a fetuin-agarose column. Electrophoretical analyses indicated that this lectin, designated P. japonica agglutinin (PJA), is an acidic protein with a molecular mass of 16 kDa, and has no intermolecular disulfide bonds. PJA induced hemagglutination activity in human ABO, mouse, rat, and rabbit erythrocytes. This activity was inhibited by sialic acid and sialoglycoproteins, but not by any other carbohydrates. PJA was stable at pH 4.0-8.0, and at temperatures below 55 degrees C. The activity of PJA was independent of EDTA and divalent cations. In addition, PJA exerts cytotoxic effects on the following cancer cell lines: human stomach cancer SNU-1, human pancreas cancer AsPc-1, and human breast cancer MDA-MB-231.
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PMID:A sialic acid-specific lectin from the mushroom Paecilomyces Japonica that exhibits hemagglutination activity and cytotoxicity. 1557 26

Combining a T9/9L glioma vaccine, expressing the membrane form of M-CSF, with a systemic antiangiogenic drug-based therapy theoretically targeted toward growth factor receptors within the tumor's vasculature successfully treated >90% of the rats bearing 7-day-old intracranial T9/9L gliomas. The antiangiogenic drugs included (Z)-3-[4-(dimethylamino)benzylidenyl]indolin-2-one (a platelet-derived growth factor receptor beta and a fibroblast growth factor receptor 1 kinase inhibitor) and oxindole (a vascular endothelial growth factor receptor 2 kinase inhibitor). A total of 20-40% of the animals treated with the antiangiogenic drugs alone survived, while all nontreated controls and tumor vaccine-treated rats died within 40 days. In vitro, these drugs inhibited endothelial cells from proliferating in response to the angiogenic factors produced by T9/9L glioma cells and prevented endothelial cell tubulogenesis. FITC-labeled tomato lectin staining demonstrated fewer and constricted blood vessels within the intracranial tumor after drug therapy. Magnetic resonance imaging demonstrated that the intracranial T9 glioma grew much slower in the presence of these antiangiogenic drugs. These drugs did not affect in vitro glioma cell growth nor T cell mitogenesis. Histological analysis revealed that the tumor destruction occurred at the margins of the tumor, where there was a heavy lymphocytic infiltrate. Real-time PCR showed more IL-2-specific mRNA was present within the gliomas in the vaccinated rats treated with the drugs. Animals that rejected the established T9/9L glioma by the combination therapy proved immune against an intracranial rechallenge by T9/9L glioma, but showed no resistance to an unrelated MADB106 breast cancer.
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PMID:Antiangiogenic drugs synergize with a membrane macrophage colony-stimulating factor-based tumor vaccine to therapeutically treat rats with an established malignant intracranial glioma. 1572 59

Galectins, beta-galactoside binding proteins, expressed selectively in human breast carcinoma are attractive targets to employ lectin-aimed therapeutics. We examined beta-galactoside binding potency of neoplastic cells using fluorescein-labelled synthetic glycoconjugates as probes for flow cytometry. As a result, surface beta-galactoside binding proteins/galectins were discovered on mouse mammary carcinoma cells in vitro and in vivo unlike non-malignant cells from the several tissues; and asialo-GM1 ganglioside carbohydrate part--containing probe was the most specific one. However, in liver and lung metastatic cells galectins seem to be expressed within cytoplasm and/or nuclei. Galectin expression correlated directly with aggressive tumour potential in the A/Sn transplantable model similar to findings in several human breast carcinoma cell lines. However, galectin expression was reduced during tumour progression in more aggressive forms of spontaneous BLRB mammary carcinomas like it was shown for human breast carcinoma specimens. Analysis of the histopathological data led, however, to the conclusion that galectin expression hardly might be a suitable marker of aggressiveness of heterogeneous mammary carcinomas as the observed level of galectin expression is influenced by the amount of the stroma in a tumour sample and/or probably, galectin expression inversely correlates with tumour aggressiveness during the initial and advanced steps of mammary tumour progression. We conclude that surface beta-galactoside binding proteins/galectins that are selectively expressed during mouse mammary carcinoma progression, similarly to human breast carcinomas, seem to be proper targets for asialo-GM1-vectored cytotoxics and our mouse model system might be a relevant instrument to further test novel modes of anti-breast cancer therapy.
Breast Cancer Res Treat 2005 Jun
PMID:Galectins as markers of aggressiveness of mouse mammary carcinoma: towards a lectin target therapy of human breast cancer. 1595 56


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