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Query: UMLS:C0006142 (breast cancer)
 160,383 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

An attempt was made to classify human pituitary cell types by electron microscopic immunohistochemistry. The immunoperoxidase technique involving the use of the peroxidase-antiperoxidase complex was applied to thin sections of human pituitaries removed surgically for breast cancer or diabetic retinopathy. Using specific antibodies against human PRL, GH, beta-FSH, beta-LH, beta-TSH, and porcine ACTH, the localization of each hormone was studied. Identification of 5 human pituitary cells was possible: 1) The PRL-secreting cell contains round or slightly ovoid secretory granules of a diameter of 275-350 nm. 2) The GH-secreting cell is densely granulated with granule diameters ranging from 350-500 nm. 3) The gonadotrophic cell, which stains for both beta-FSH and beta-LH, is characterized by the presence of a varying number of secretory granules ranging from 275-375 nm. 4) The cortico-lipotrophic cell has numerous granules of about 375-550 nm in diameter. 5) The TSH-secreting cell contains small secretory granules of about 125-200 nm in diameter. Another cell type of which the small secretory granules of about 100 nm in diameter could not be stained by any of the antisera was also observed. This ultrastructural identification of human pituitary cells should contribute to a better understanding of the pathophysiology of the human pituitary.
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PMID:Identification of human anterior pituitary cells by immunoelectron microscopy. 22 40

Aldehyde-resistant, diaminobenzidine-stained endogenous peroxidases form ideal markers for the biochemical endpoints of hormone stimulation and differentiation of certain mammalian cells and tissues. The lactoperoxidase (LPO)-type of endogenous peroxidases are synthesized by the acinar cells of the salivary, Harderian, lacrimal and mammary glands and are present in their secretions. These LPO-type enzymes, that are inhibited by cyanide and aminotriazole, appear to operate extracellularly as bactericidal agents in milk and in other biological fluids. In the mammary gland, lactoperoxidase is a consistent marker enzyme for differentiated acinar cells engaged in lactogenesis. Myeloperoxidase (MPO)-type endogenous peroxidases are prominent markers for the GERL endomembrane system and differentiated lysosomes in certain cells of the reticuloendothelial system and phagocytes. MPO is prominent within eosinophils, peritoneal macrophages and in Kupffer cells. The MPO-type endogenous peroxidases function primarily within lysosomes as bactericidal agents. Thyroid peroxidase (TPO) is relegated to the cisternae of the granular endoplasmic reticulum and Golgi apparatus, to apical cytoplasmic vesicles and to the luminar cell membrane surface of acinar cells. The enzyme is probably activated at release and functions both in the organification reaction (T leads to To) and in the biosynthesis of thyroxine. Thyroid stimulating hormone (TSH) appears to play a key role in the regulation of TPO levels and activity in the thyroid gland. Certain tissues displaying growth-dependency on estrogen (i.e., uterus, cervix, vagina and the DMBA-induced rat mammary tumor) synthesize and secrete endogenous peroxidase into their lumina. These enzymes serve as important marker proteins of estrogen action, in that they occur distal to the binding of estrogen to its receptor protein. Estrogen antagonists, particularly CI-628 (Parke-Davis) and Nafoxidine (Upjohn) that appear to function through the estrogen receptor mechanism, also induce synthesis of the reproductive tract endogenous peroxidase but inhibit growth of these tissues. Progesterone antagonizes the synthesis of the reproductive tract peroxidases and inhibits growth of the tissues as well, in part, through the reduction of the cytosol estrogen receptor protein. Endogenous peroxidase activity appears to represent a reliable marker for rodent breast cancer tissues displaying dependency for estrogen and is of potential interest as a diagnostic marker protein in human breast cancer. Rat uterine peroxidase (UP) has been investigated by microelectrophoretic techniques. The molecular weight of UP has been determined in the range of 100,000 by using polyacrylamide gradient gels in the absence and presence of nonionic and anionic detergents. The isoelectric point of UP is located between pH 4.5 and 5.9. Employing the two-dimensional combination of isoelectric focusing and gel gradient electrophoresis, UP was separated into two subunits, one having a molecular weight of 70,000, the other less than 20,000.
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PMID:Mammalian endogenous peroxidases as cellular markers and as biosynthetic endpoints of hormone-mediated activity: viewpoint from cytochemistry. 22 20

Several major defects in the estrogen receptor pathway have been evidenced in most human breast cancers by an immunofluorescence tracing of estradiol receptor complexes at the single cell level. Endogenous peroxidase seems a reliable postreceptor marker for estrogen-sensitive breast cancer cells. Since almost all human breast cancers appear to include both hormone-sensitive and autonomous cell populations, a combined use of endocrine and cytotoxic regimens is urged. The hormonal regulation of tumor growth parameters could be exploited in order to achieve a maximum recruitment of synchronized tumor cells at risk to chemotherapy.
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PMID:Estrogen receptors and post-receptor markers in human breast cancer: a reappraisal. 35 48

An estrogen-induced, intensely staining peroxidase 3,3-diaminobenzidine-positive reaction product is found to be characteristic of hormone-dependent, 7,12-dimenthylbenz(a)anthracene-induced mammary tumors of the rat. This product is demonstrated in thick sections of such tumors from intact or estrogen-treated castrate rats but is not seen in tumors that are in regression due to castration or estrogen deprivation. It is, furthermore, absent from tumors whose growth is unaffected by castration. The subcellular localization of this enzyme activity is restricted mainly to the nuclear envelope and cisternae of the granular endoplasmic reticulum in addition to secretory granules. This provides the first evidence for a criterion that would allow differentiation of hormone-dependent and hormone-independent mammary cancer on histological sections and, as such, may have considerable potential as an aid in the classification of human breast cancer.
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PMID:Identification, subcellular localization, and estrogen regulation of peroxidase in 7,12-dimethylbenz(a)anthracene-induced rat mammary tumors. 110 86

Data derived from a correlated morphological and biochemical study suggest the following: (a) estradiol-17beta, diethylstilbestrol, the estrogen antagonists nafoxidine (Upjohn 11,000), and Parke Davis C1628 induce synthesis of an endogenous peroxidase in the epithelium of target tissues like the vagina, the cervix, the uterus, and in the acinar cells of the estrogen-dependent rat mammary tumor; (b) peroxidase is a "specific" secretory protein of the estrogen-sensitized uterine endometrium; (c) peroxidase synthesis is not a nonspecific response to steroid hormone action, since progesterone and testosterone do not induce its synthesis; (d) endogenous peroxidase is a possible diagnositc protein for the detection of estrogen-dependent growing tissues, including breast cancer; (e) movement of exogenous horseradish peroxidase from the interstitium to the uterine lumina is restricted by tight junctions located at the apices of epithelial cells. Estrogen and antagonists do not appear to influence the transepithelial movement of exogenous peroxidase into the lumen.
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PMID:Endogenous peroxidase: specific marker enzyme for tissues displaying growth dependency on estrogen. 117 Nov 6

The protective effect of dietary fiber on breast cancer development might be explained by the interaction between dietary fiber and hormonal processes. We studied the effects of dietary fiber and the effects of a reduced energy intake on the exposure of mammary tissue to both estrogens and progesterone, as well as the blood plasma levels of these steroids and of LH and FSH. Adult female Fisher rats were fed ad libitum either a low-fiber diet (0.5% dietary fiber based on wheat flour) or a high-fiber diet (9.2% dietary fiber based on wheat bran). A third group was used to control for the reduced energy intake of the high-fiber group and was fed the low-fiber diet restricted. Energy intake was similar for the second and third groups. Four out of 14 rats of the high-fiber group and 4 out of 15 rats of the restricted low-fiber groups were not in cycle after seven weeks on the experimental diets, indicating that the estrous cycle was significantly affected by a reduced energy intake. Exposure of mammary tissue to estrogens did not differ among the groups, as measured by estrone, estradiol-17 beta, estriol and peroxidase activity. During the peak period, plasma LH levels were significantly higher in the high-fiber group than in the two low-fiber groups. FSH and progesterone plasma levels were unaffected by the experimental diets. It is concluded that dietary fiber affects the hormonal processes involved in breast cancer development. The increased LH levels indicate an increased estrogen production in the ad libitum high-fiber group.
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PMID:Effects of wheat bran on blood and tissue hormone levels in adult female rats. 132 21

The expression of oncogene products related to cell growth (c-erbB-2, c-myc, ras p21, EGFR) was investigated in benign (15 cases) and malignant breast lesions (20 cases) by means of immunohistochemistry using the avidin-biotin-peroxidase technique with polyclonal and monoclonal antibodies. The aim of this study was to evaluate the relationship between the staining positivity and various morphological and biological features, such as tumour type, grading, hormone receptor status and cell kinetic parameters. In benign breast lesions, as expected, the kinetic parameters were low, both for Ki-67 and LI. All the specimens showed a diploid condition (the DI being equal to 1) and we found a limited degree of immunoreactivity for all the growth factors and oncogene products. In breast cancer we studied the distribution of immunohistochemical positivity for EGFR, c-erbB-2, c-myc, ras p21 and Ki-67, which was related to age, nodal status, ER and PgR receptor status, LI, DI and histopathological grading. A significant positive correlation was found both between ras p21 expression and nodal status and ER-ICA positivity. We observed a strong correlation between LI and Ki-67 and an inverse relation between Ki-67 and ER expression. These findings suggest the importance of studying the relationship between prognostic factors which may provide preoperative prediction in the biological behaviour of breast cancer, not only on biopsy specimens, but also on fine needle aspirates.
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PMID:Preliminary study on oncogene product immunohistochemistry (c-erbB-2, c-myc, ras p21, EGFR) in breast pathology. 134 7

The PC-10 monoclonal antibody to PCNA was employed to analyze proliferative grade in conventionally-formalin fixed, paraffin-embedded tumour samples of 162 patients with primary breast carcinoma. To perform the immunocytochemical method, sections were not heated, were de-waxed using alcohol, and then immersed in a phosphate-buffered saline solution and in methanol with 0.5% hydrogen peroxide to block endogenous peroxidase activity. Immunostaining was performed by a streptavidin-biotin peroxidase substrate. A semiquantitative scoring system was used to evaluate the fraction of nuclei that were PCNA-positive. The score ranged from 0% to 75% with a median value of 25%, mean of 27.8 +/- 1.5. PCNA staining was significantly associated with oestrogen receptor-negativity (p = 0.011) and correlated, but not at a statistically significant level, with tumour size (p = 0.08). No significant association was observed between PCNA and node status, grading, DNA ploidy, progesterone receptor or menopausal status. Prognostic indices such as number of positive lymph nodes and DNA ploidy were significantly associated with relapse-free survival (RFS) and overall survival (OS). No significant correlation between PCNA nuclear immunostaining and RFS or OS was observed after a median follow-up of 4 years. Our results indicate that analysis of PCNA alone does not seem to be a useful marker in identifying patients at different prognosis in human breast cancer.
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PMID:PC-10 antibody to proliferating cell nuclear antigen (PCNA) is not related to prognosis in human breast carcinoma. 136 82

Malignant transformation of human cells is associated with morphological and biochemical alterations. We have studied the distribution and pattern of staining of HMFG2 (human milk fat globulin) in normal breast, benign breast lesions, and 137 primary and metastatic breast carcinomas. Immunohistochemical staining was performed with an antibody to HMFG2 using the indirect peroxidase technique. Three patterns of staining were noted: 1) secretion and luminal staining (in normal breast, most benign breast lesions and some breast carcinomas); 2) plasma membrane staining (in breast carcinomas); 3) intracytoplasmic staining (in breast carcinomas). Immunoelectron microscopy was also performed on normal breast, infiltrating duct, and lobular carcinomas. Immunoelectron microscopy showed localization of the gold particles on the electron dense granules of the HMFG2 protein. These were localized along the surface of the extracytoplasmic lumina in normal breast ducts/acini and breast carcinomas, whereas localization was also noted within the intracytoplasmic lumina in cancer cells only. These results show that there is altered localization of milk fat globulin in breast cancer cells associated with membrane internalization and formation of intracytoplasmic lumina. This contributes to the understanding of the phenotypic alterations associated with malignant transformation in breast cancer.
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PMID:Subcellular localization of HMFG2 in breast carcinomas: an immunohistochemical and immunoelectron microscopic study. 136 93

The lining epithelium of the human cervix uteri is an estrogen dependent tissue containing specific intracellular receptors for this hormone. However, the influence of estrogen on an early neoplastic lesion arising from this epithelium, such as carcinoma in situ of the cervix, has not been determined. We evaluated 24 formalin fixed paraffin embedded tissue specimens of cervical carcinoma in situ for the presence of estrogen receptor by the immunoperoxidase technique. The antigenic sites of estrogen receptor were exposed by DNAse treatment followed by peroxidase-antiperoxidase (PAP) staining with monoclonal antibody against estrogen receptor. Parallel negative controls were run using negative control antibody and rat serum. Quality control for positive staining was performed using breast cancer tissue sections from specimens with known estrogen receptor detected by the radioreceptor method. Strongly positive staining was observed in all specimens in the nuclei of glandular epithelium, stromal cells, and basal and parabasal cells. However, nuclei within carcinoma in situ of the cervix showed no evidence of positive staining. Due to lack of specific intracellular receptor for estrogen, it appears that carcinoma in situ of the cervix will not be under direct influence of estrogen.
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PMID:Estrogen receptor in carcinoma in situ of the cervix. 137 Nov 75


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