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D R Ciocca

Publications and source records attributed to D R Ciocca.

At least 55 records · Page 3Linked to original sources
PubMed1989

Ultrastructural and immunoelectron-microscopic study of the human pharyngeal hypophysis.

The ultrastructural characterization of seven cell types in the pharyngeal hypophysis from adult subjects is described. By immunoelectron microscopy, two of the granular cell types were identified as growth-hormone- and prolactin-producing cells. The vascular supply of this gland was mainly composed of capillaries without fenestrations. Review of the literature allows a comparison with the ultrastructure of the sellar adenohypophysis and with the pharyngeal hypophysis of children.

Adult↗
PubMed1987

Intensification of the immunocytochemical reaction by staining both sides of tissue sections.

We describe how the efficiency of immunostaining may be increased by staining paraffin sections on both sides. This modification exposes more antigenic binding sites per unit tissue area, as shown by the peroxidase-antiperoxidase and the avidin-biotin-peroxidase complex methods. Using antigen-rich tissue samples, the modified procedure made it possible to use more dilute primary antiserum or to reduce the incubation time of the tissue with the primary antibody. Alternatively, in tissue samples with sparse antigenic sites, the procedure made it possible to visualize and document very weak immunoreactivities.

Animals↗
PubMed1986

Localization of an estrogen-responsive protein in the human cervix during menstrual cycle, pregnancy, and menopause and in abnormal cervical epithelia without atypia.

The presence and distribution of an estrogen-responsive protein with a molecular weight of 28,000 were investigated in the human cervix with use of a monoclonal antibody. This biochemical marker protein was localized with a light microscope and by immunocytochemical studies of the different cell types and cell layers of the cervix. The study involved 60 patients, 48 of whom were sexually active, eight pregnant, and four in menopause; strips of endometrial tissue were analyzed in 22 patients. In cycling women the estrogen-responsive protein was identified in the subcolumnar cells of the endocervix, whereas in the ectocervix the protein was detected mainly in the parabasal and intermediate cell layers but alternating with unstained areas. There were no significant variations in the presence of the protein in the ectocervical and endocervical epithelium during the different phases of the menstrual cycle. During pregnancy a more intense and homogeneous immunostaining of the protein was seen in the ectocervix, endocervical areas with squamous metaplasia showed strong estrogen-responsive immunostaining, and predecidual and decidual cells were positive for the protein. There were no prominent changes in the presence and distribution of the protein in the abnormal ectocervical samples without atypia. However, in the endocervix the protein detection was useful to follow the evolution of the subcolumnar cells to simple squamous metaplasia. These samples displayed intense estrogen-responsive immunostaining. No immunoreaction was observed in the cervix of menopausal women. The results of the present study have shown that the response of the normal uterine cervix to estrogenic influence is heterogeneous in different cervical cell types and in different sites within the same cell layer; during the normal menstrual cycle the capability of response of the cervical cells to variations of estrogen levels is limited when compared with the endometrium; and during pregnancy and in the process of indirect squamous metaplasia some of the cervical cells seem to be very reactive to estrogenic stimulation. This study defines the normal baseline for further analysis of the estrogen-regulated protein in the uterine cervix during abnormal growth.

Acanthosis Nigricans↗
PubMed1986

An estrogen-regulated protein in normal and malignant endometrium.

The presence and distribution of a protein with a mol. wt of 24,000 (24K) was determined in endometrial biopsies from regularly cycling women and in women with endometrial carcinoma. This protein, of as yet unknown function and originally found in a breast cancer cell line, was detected by immunohistochemistry using a monoclonal antibody. In regularly cycling women, the 24K protein began to appear in the glandular epithelium during the late proliferative phase and decreased after ovulation. In contrast, in the superficial epithelium, the strongest immunostaining was observed during the secretory phase. Superficial epithelial cells expressed maximal 24K immunoreactivity around day 21 of the cycle and it was clearly seen in the bulbous projections of the apical cytoplasm. These results suggest that the 24K protein may be a marker for hormonal events in the endometrium during the menstrual cycle. In endometrial carcinoma, 24K was correlated with low tumor histologic grade, few mitotic figures, few nucleoli and a low degree of nuclear pleomorphism. These data suggest that 24K may be a potential marker of tumor differentiation.

Antibodies, Monoclonal↗
PubMed1986

Expression of an estrogen-regulated protein in rat testis Leydig cells.

Previous studies have demonstrated that the induction of an estrogen-regulated protein precedes the desensitization of microsomal enzymes after in vitro treatment of Leydig cells with hCG or estradiol (E2). This protein is recognized by a monoclonal antibody against an estrogen-dependent protein of mol. wt 28,000 from MCF-7 cells [Science 226 (1984) 445]. In the present study, this antibody was used to investigate the ontogenesis of this protein, to analyze its regulation after hormonal treatments under in vitro conditions and to determine its subcellular localization. The study was performed at light and EM levels using immunocytochemical techniques. The estrogen-regulated protein was detectable with low reactivity in the fetal testis and was undetectable from birth to 20 days. During the latter period, Leydig cell are in a quiescent phase of their maturation, with low aromatase activity and low estrogen and testosterone production. Thereafter, increasing immunostaining from 20 to 60 days was observed concurrent with Leydig cell maturation. Reactivity was constant throughout adulthood. The in vitro studies demonstrated that the synthesis of the protein in culture of adult Leydig cells is stimulated by hCG via the action of endogenous estrogen and is prevented by pretreatment with tamoxifen. The presence of the specific immunoreactive protein in E2-treated Leydig cells and uterine cells from E2-treated animals was also demonstrated by Western blot analysis. This is a long-lived protein, and 3 h of E2 stimulation are required to produce an immunocytochemical change. Pretreatment with cycloheximide prevented the increase in synthesis induced by E2. At the EM level (specific antibody/protein A-gold), the protein was detected in moderate amount mainly in the cycloplasmic matrix and close to the cisternae of the rough and smooth endoplasmic reticulum. Unlike the MCF-7 cell protein, it is not associated with secretion granules. The low reactivity observed in fetal cells is attributable to maternal estrogen affecting a small pool of estrogen receptors that is not sufficient to mediate the regulation observed in adult rats. Assessment of the estrogen-regulated protein by immunocellular techniques provides a sensitive index of estrogen receptor mediated action. This protein could be involved in intracellular modulatory function(s) in the Leydig cell.

Animals↗
PubMed1986

Human pharyngeal and sellar pituitary glands: differences and similarities revealed by an immunocytochemical study.

Fifteen pharyngeal and sellar pituitary glands, obtained at autopsy from unselected adult patients, were compared in an attempt to elucidate the functional significance of the pharyngeal pituitary. The study was carried out using light microscopy and an indirect peroxidase technique to detect the presence of prolactin, GH, ACTH, LH, FSH, TSH and lipotrophin (LPH) immunoreactive cells. A quantitative analysis of these cell types in each gland was performed. Neither the pharyngeal nor the sellar pituitaries were abnormal in six cases. In this group the average percentage of immunoreactive cells in the sellar vs the pharyngeal pituitary was 11.3 vs 7.4 for FSH cells, 13.3 vs 4.4 for LH cells, 6.4 vs 5.2 for TSH cells, 14 vs 1.5 for ACTH cells, 13.1 vs 6 for LPH cells, 29.4 vs 5.2 for GH cells and 21.2 vs 8.5 for prolactin cells. A comparative statistical evaluation of the seven hormone-producing cell types indicated that, in most cases, the percentage of immunoreactive cells was significantly higher in the sellar pituitary. Examination of serial sections revealed hyperplasia, with or without microadenomas, in nine sellar pituitaries. In these abnormal cases most of the pharyngeal pituitary glands showed hyperplasia of the same cell type as was found hyperplastic in the sellar adenohypophysis. However, hyperplasia restricted to the sellar pituitary was also seen. There were two cases in which the pharyngeal pituitary was almost lacking in immunoreactive cells; in one of them the sellar pituitary had GH and prolactin cell hyperplasia. The results obtained confirm that under normal conditions the pharyngeal pituitary is not an important source of adenohypophyseal hormones.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1985

Immunocytochemical evidence for the ability of the human pharyngeal hypophysis to respond to change in endocrine feedback.

Two pharyngeal hypophyses from patients with endocrine disorder were examined light microscopically and immunocytochemically. The pharyngeal hypophysis from a patient with primary hypothyroidism was hypertrophic, with TSH cell hyperplasia; while that from a patient treated with metoclopramide, a dopamine-receptor-blocking drug, showed PRL cell hyperplasia. These findings strongly suggest that under certain circumstances the pharyngeal hypophysis is able to respond with specific changes to variations in the endocrine feedback.

Adenoma↗
PubMed1985

The presence of an estrogen-regulated protein detected by monoclonal antibody in abnormal human endometrium.

The cellular localization of a 24,000 (24K) mol wt protein was evaluated by monoclonal antibody immunocytochemistry in atrophic and persistent proliferative endometrium as well as in various forms of hyperplastic and neoplastic human endometria. 24K was chiefly located in the cytoplasm of ciliated cells and their precursor forms, clear cells. It was absent in atrophic, resting, and regressive forms of cystic glandular hyperplasia. Persistent proliferative endometria with a low degree of proliferation has occasional 24K immunostained cells, whereas those with active proliferation contained intense 24K immunostaining. A similar pattern characterized the active forms of cystic glandular hyperplasia. The immunostaining reaction decreased in adenomatous and atypical adenomatous hyperplasia as well as in well differentiated adenocarcinomas. In poorly differentiated carcinomas, 24K protein was virtually absent. These findings suggest that 24K protein is estrogen and ciliated cell related, and endometrial ciliogenesis and 24K protein are morphological and biochemical markers, respectively, of the estrogenic endometrial response. Their increase and decrease in hyperplastic and neoplastic endometria support the concept that early hyperplasia is highly sensitive to estrogenic stimulation, whereas with increasing architectural and cytologic atypia, the estrogenic response decreases as a reflection of growing cell populations that are independent of estrogenic influence. Immunostaining with 24K is not sensitive enough to discriminate estrogen-independent cells of atypical adenomatous hyperplasia from those of early, well differentiated adenocarcinoma.

Adult↗
PubMed1985

Identification of seven hormone-producing cell types in the human pharyngeal hypophysis.

Eight adult human pharyngeal pituitary glands taken at autopsy were studied by immunocytochemistry to reveal the presence of ACTH-, lipotropin-, FSH-, LH-, TSH-, PRL-, and GH-immunoreactive cells. All of these cell types were found and quantitated in pharyngeal hypophyses from patients with no evidence of endocrine disorder. The percentage of the seven hormone-producing cell types varied from gland to gland from 1-30%; there were no marked histological differences between sexes or attributable to age. The cellular composition of the pharyngeal hypophysis shows that this gland has the capacity to produce at least seven hormones.

Adult↗
PubMed1984

Estrogen-dependent Leydig cell protein recognized by monoclonal antibody to MCF-7 cell line.

A protein (27,000 molecular weight) was previously found in rat Leydig cells after treatment with estradiol (E2) and human chorionic gonadotropin (hCG) in vitro. The effect of hCG occurred through increased E2 production. This hormone-regulated rat testicular protein was compared to an estrogen-regulated protein of similar physical characteristics isolated from a human mammary cancer cell line (MCF-7) and present in normal human estrogen target organs. The Leydig cells from rat and human tissue showed specific immunofluorescence and immunoperoxidase staining in the cytoplasm upon incubation with a monoclonal antibody (C11) to the estrogen-regulated protein from MCF-7 cells. Leydig cells after exposure to E2 or hCG showed the highest fluorescence intensity; this intensity was reduced by treatment with Tamoxifen. No reaction was associated with other testicular cells. The estrogen-regulated protein from human cell lines is therefore immunologically similar to that from the rat Leydig cell. The monoclonal antibody should be useful for further characterization of the Leydig cell protein.

Adult↗
PubMed1984

Estrogen-induced 24K protein in MCF-7 breast cancer cells is localized in granules.

We have previously reported the production of monoclonal antibodies which detect, by immunohistochemistry, an estrogen-induced protein of molecular weight 24,000 daltons (24K). This protein, of unknown function, has been detected in: a) estrogen receptor-positive breast cancer cell lines but not in receptor-negative lines; b) several human normal estrogen target organs; and c) certain human carcinomas, including breast tumors. To examine the subcellular localization of this 24K estrogen-induced protein, we have done immunohistochemical studies at light and electron microscopic levels using a human breast tumor cell line (MCF-7) grown in vitro and also in nude mice in vivo. MCF-7 cells grown in the ascites fluid of nude mice and processed for paraffin sections showed a defined polarity, and the 24K protein was localized in the apical cytoplasm of the cells. After cytocentrifugation, MCF-7 cells grown in vitro displayed 24K protein mainly confined to large cytoplasmic granules. The presence of 24K protein in cytoplasmic granules was also seen by immunoelectronmicroscopy in MCF-7 cells grown both in vitro and in vivo. The granules had different sizes, shapes, and 24K immunostaining intensity. The morphological evidence suggests that the 24K estrogen-induced protein is secreted from the cells.

Animals↗
PubMed1984

Constitution and behavior of follicular structures in the human anterior pituitary gland.

The follicular structures present in the human pituitary gland were studied, at the light-microscopic level, using histochemical and immunocytochemical techniques. The antisera applied in the peroxidase-antiperoxidase procedure were anti-hFSH beta, anti-hLH beta, anti-hPRL, anti-hGH, anti-hTSH beta, anti-hLPH beta, anti-pACTH, and anti-hACTH. In the 10 normal pituitaries examined, follicles were always found in the three areas of the adenohypophysis. The wall of the pars distalis follicles showed the seven immunoreactive cell types studied, while follicle-stimulating hormone (FSH) and luteinizing hormone (LH) cells were the only ones present in the wall of the pars tuberalis follicles. Most of the cell types studied were also present in the wall of the intermediate area follicles, but these follicles had characteristics not found in the other two areas. They were very large, with frequent interconnections forming a three-dimensional network of anastomotic cavities, and the colloid had different histochemical affinity. None of the hormones studied could be detected by immunocytochemistry within the follicular colloid. Three of the ten pituitary adenomas examined showed numerous follicular structures. Some of the follicles in the adenomatous pituitaries were similar to those found in the normal adenohypophysis, but there were also follicles filled with only traces of colloid and numerous blood cells in the cavity, and follicles filled with neoformed connective tissue. In one of these cases, FSH/LH immunoreactive adenoma cells were seen in the wall of the follicles. The results obtained suggest that the finding of pituitary adenomas with follicular structures is not uncommon and that the follicles originate from the tumor cells. In addition, the follicles seem to have several functional stages, explaining the finding of different types of follicular formation.

Adenoma↗
PubMed1983

Monoclonal antibody storage conditions, and concentration effects on immunohistochemical specificity.

Monoclonal antibodies against a 24,000 dalton intracellular estrogen-regulated protein in human breast cancer cells were used to study storage conditions and the effects of monoclonal antibody concentrations on immunohistochemical antigen localization. Both hybridoma supernatants and ascites fluid obtained from mice injected with hybridoma cells were used as sources of monoclonal antibodies; the monoclonal antibodies in the ascites fluid were concentrated and purified. Both antibody preparations were stored at 4, -20, or -70 degrees C and periodically tested for activity at these storage conditions. There was no difference in activity for the antibodies between storage at -20 and -70 degrees C. However, when highly diluted antibody was stored at 4 degrees C, the activity was lost within 2 weeks if carrier proteins were not added. These monoclonal antibodies were applied to immunohistochemical staining of different mouse and human tissues processed for routine paraffin sections, using the avidin-biotin-peroxidase procedure. A monoclonal antibody of unrelated specificity was used as control. When these antibodies were used at high concentrations, all the different tissues examined were immunostained. With reduction of the antibody concentration, an immunohistochemical dissection of the tissues was seen until specific immunostaining was reached. When even more highly diluted monoclonal antibody was used, heterogeneity in the staining pattern became very high. On the basis of these results, certain immunohistochemical criteria are proposed for the selection of the optimum concentration of monoclonal antibodies for specific antigen detection.

Animals↗
PubMed1983

Evidence for modulation of a 24K protein in human endometrium during the menstrual cycle.

The presence and distribution of a protein with a molecular weight of 24,000 (24K) was determined in endometrial biopsies from regularly cycling women. This protein, of as yet unknown function and originally found in a breast cancer cell line, was detected by immunohistochemistry using a monoclonal antibody. In the glandular epithelium, the 24K protein began to appear during the late proliferative phase and decreased after ovulation. In contrast, the strongest immunostaining was observed in the superficial epithelium during the secretory phase. In these cells, the 24K immunoactivity reached the maximum around day 21 of the cycle and was clearly seen in the bulbous projections of the apical cytoplasm. These results suggest that the 24K protein may be a marker for hormonal events during the menstrual cycle.

Cytoplasm↗
PubMed1983

Molecular and cellular basis of the mammary gland susceptibility to carcinogenesis.

Mammary carcinomas induced by the administration of 7,12-dimethylbenz(a)anthracene (DMBA) to young virgin rats arise from undifferentiated terminal ductal structures called terminal end buds (TEBs). TEBs that normally differentiate into alveolar buds (ABs) and lobules under the influence of DMBA develop intraductal proliferations which progress to carcinoma. The high susceptibility of the young virgin rat TEBs to neoplastic transformation is due to its large proliferative compartment, with cells cycling every 10 hr, and to a higher (3)H-DMBA uptake. Progressive differentiation of TEBs into ABs and lobules or their regression to terminal ducts (TDs) is seen with aging. Complete differentiation of the gland is attained only through pregnancy and lactation. The greater differentiation of the gland is manifested as permanent structural changes, consisting in the disappearance of TEBs and in a diminution of the number of TDs due to their differentiation into ABs and lobules. This greater differentiation results in a diminished or total refractoriness of the gland to the carcinogen because ABs and lobules have a lower proliferative compartment and a longer cell cycle than TEBs and TDs. Cells of parous rats have both in vivo and in vitro a lower DMBA-DNA binding capacity, a lower DNA synthesis and a greater ability to repair DMBA damaged DNA than cells of young virgin rats. The more efficient DNA repair capacity of the parous rat mammary gland is demonstrated by the induction of unscheduled DNA synthesis and a removal of DMBA-DNA adducts.

9,10-Dimethyl-1,2-benzanthracene↗