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N Papadopoulos

Publications and source records attributed to N Papadopoulos.

At least 73 records · Page 4Linked to original sources
PubMed2002

Gains and losses of glycoprotein CD44 and secretory component expression in endometrial hyperplasia and neoplasia.

CD44 is an adhesion molecule, which binds hyaluronic acid and participates in a number of cell-cell interactions, including lymphocyte homing. The CD44 antigen is expressed on approximately 90% of lymphocytes, monocytes, granulocytes, and, in lower amounts on thymocytes, fibroblasts, and erythrocytes. Platelets lack CD44. In non-haematopoietic tissues, CD44 is widely distributed. The secretory component is isolated from human colostrum and is of help in more precise grading of endometrial carcinoma. In this study we examined CD44 and secretory component expression in adenomatous hyperplasia, atypical adenomatous hyperplasia and well-differentiated adenocarcinoma (cribriform pattern). The results showed decreased expression of CD44 and increased expression of secretory component as the lesion progressed to malignancy.

Adenocarcinoma↗
PubMed2002

Immunohistochemical expression of alpha-smooth muscle actin in infiltrating ductal carcinoma of the breast with productive fibrosis.

Myoepithelial cells are normally located between the epithelial cells and the basal lamina of secretory elements of exocrine glands. Their role in the histogenesis of breast tumours has been studied extensively, and a definite differentiation towards myoepithelial cells has been demonstrated in adenoid cystic carcinoma, adenomyoepithelioma, low-grade adenosquamous (syringomatous) carcinoma, pure malignant myoepithelioma and poorly differentiated myoepithelial-rich breast carcinoma. All these tumours are of low malignancy, with the exception of malignant myoepithelioma and poorly differentiated myoepithelial-rich carcinoma. We examined the possibility that invasive ductal carcinoma of the breast might show differentiation towards both epithelial and myoepithelial cells because there is no reason to assume that one type of differentiation necessarily excludes the other. We performed the avidin-biotin immunohistochemical analysis of 20 cases of infiltrating ductal carcinomas (IDCs) with diffuse fibrosis, 20 cases of IDCs without fibrosis and five cases of metaplastic carcinomas, to detect myoepithelial differentiation of the tumour cells. Myoepithelial differentiation was determined by the expression of alpha-smooth muscle actin (alpha-SMA). We concluded that IDCs with diffuse fibrosis are associated with a myoepithelial immunophenotype of carcinoma cells.

Actins↗
PubMed2002

Immunocytochemical profile of malignant pleural effusions of small-cell lung cancer.

BACKGROUND: Small-cell lung carcinoma (SCLC) is a highly malignant tumour of a somewhat distinctive cell type. The aim of this study was to determine the immunocytochemical profile of tumor cells and lymphoid cell in SCLC pleural fluids. METHODS: Nine cases of malignant pleural fluids of SCLC were studied using cell block preparation. In pleural effusions cytologically proven to be malignant in 9 patients with SCLC, the immunocytological features of tumor cells, together with the determination of lymphocytic subsets were documented. RESULTS: In all 9 cases, tumor cells reacted with neuron-specific enolase (NSE) (100%), whereas in 6 of 9 cases (66,66%) tumor cell expressed synaptophysin, thyroid transciption factor-1 (TTF-1) and chromogranin A antigens. Phenotyping of the lymphocytes revealed in the majority of cases an expression of CD3 and CD4 antigens (8 and 7 cases, respectively) in contrast to CD8 and CD20 expression (1 and 1 case, respectively). CONCLUSIONS: The reactivity pattern of the tumor cells with the markers used in our study is a specific for SCLC. No significant difference in the distribution of lymphocytic subpopulations is observed in correlation with other malignant and no malignant processes involving the pleural cavity.

Antigens, CD↗
PubMed2002

Gains and losses of CD8, CD20 and CD56 expression in tumor stroma-infiltrating lymphocytes compared with tumor-associated lymphocytes from ascitic fluid and lymphocytes from tumor draining lymph nodes in serous papillary ovarian carcinoma patients.

Serous papillary ovarian cancer (SPC) is a highly aggressive tumor. About two-thirds of women have advanced disease at the time of diagnosis. Although many women with disseminated disease respond at first to combinations of surgery and chemotherapy, nearly 90% of tumors recur and women die of disease. Update progress in our knowledge of tumor-associated antigens and insight into mechanisms involved in immune-mediated recognition of these antigens, have provided a strong starting point for using the immune system as a model for novel therapy. In this study we determined the immunological profile of tumor-infiltrating lymphocytes (TILs), tumor-associated lymphocytes (TALs) in ascitic fluids, and lymphocytes from tumor draining regional lymph nodes (LNs) in SPC patients by CD20 (L26), CD8, and CD56 immunostaining. We examined 14 cases of TILs, 15 cases of TALs and 19 cases of LNs. TILs were infiltrating tumor stroma. No significant difference was detected in TILs, TALs and LNs in the expression of the B-cell marker CD20. In contrast, CD8 (T-cytotoxic) and CD56 (natural killer cell, NK) markers were dominant in LNs and TALs, but not in TILs. We conclude that SPC tumor lymphocytic infiltrate demonstrates a deplete T cytotoxic (CD8+) and NK cell (CD56+) immunophenotypic profile. This might in part explain the poor clinical outcome of the disease.

Antigens, CD↗
PubMed2001

Interferon-induced retinopathy in asymptomatic cancer patients.

OBJECTIVES: Interferon-induced ocular complications, including retinal ischemia and ischemic optic neuropathy, can be associated with significant visual loss. We report three cases of asymptomatic ischemic retinopathy in cancer patients receiving interferon. DESIGN: Retrospective, interventional, noncomparative small case series. METHODS: Retrospective review of the medical records and fundus photographs. RESULTS: Interferon-induced ischemic retinopathy can occur in asymptomatic cancer patients. The retinal changes are usually reversible with discontinuation of interferon therapy. CONCLUSIONS: These three cases underscore the importance of dilated funduscopic examination at baseline and during follow-up, at least every 3 months, for all cancer patients receiving interferon to identify retinal toxicity at its earliest stages. A prospective study evaluating the incidence and severity of interferon retinopathy in cancer patients would be prudent.

Adult↗
PubMed2001

Phase II evaluation of bryostatin-1 in metastatic melanoma.

In this phase II study we assessed the efficacy of bryostatin-1 (NSC 339555) in metastatic melanoma patients when given intravenously either once a week at a dose of 25 microg/m2 per day over 24 h for 3 weeks or at 40 microg/m2 per day over 72 h every 2 weeks. Treatment courses were repeated every 4 weeks. Patients who had received one prior chemotherapy regimen for advanced melanoma, with or without biotherapy, were randomized to one or the other bryostatin-1 dose schedules until 12 patients were registered to each arm. Because there was one confirmed response among the 12 patients who received the 72 h dose schedule, 25 more patients were added to that arm. No prophylactic medications were given. Objective tumour measurements were used to assess the efficacy of the regimen. The National Cancer Institutes common toxicity criteria were used to grade reactions. In total, 49 patients with metastatic melanoma, none having symptomatic brain metastasis, were studied. Of these, 12 patients received the 24 h bryostatin-1 regimen, while the remaining 37 received the 72 h regimen. One patient receiving the 72 h regimen had a partial response lasting over 7 months. Muscle pain occurred in over 90% of the patients and was the dose-limiting side effect of the 72 h regimen. Grade 3/4 nausea and vomiting were more common on the 24 h regimen than on the 72 h one (35% versus 5% of patients). There was no therapy-related thrombocytopenia. Neutropenia was mild and mainly limited to patients receiving the 72 h regimen. Bryostatin-1 has limited activity against melanoma when given by 72 h intravenous infusion.

Adolescent↗
PubMed2001

Appraisal of imprint cytology in the diagnosis of mucinous carcinoma of the breast: a case report.

A case of mucinous carcinoma of the breast is reported in a female aged 71 years. On gross examination of the left mastectomy specimen two relatively well-circumscribed masses with a gelatinous cut surface were found. Touch imprint cytology was consistent with a low-grade malignancy and histologic and histochemical examination revealed a mucinous carcinoma. Careful prospective correlation between the cytological appearances of cells in imprints and the subsequent histopathology may lead to a more precise cytodiagnosis of a tumor associated with a comparative good prognosis.

Adenocarcinoma, Mucinous↗
PubMed2001

Primary diffuse large B-cell lymphoma of the breast: a case report.

Mammary non-Hodgkin's lymphomas are uncommon and account for 2% of all extranodal lymphomas. Stringent diagnostic criteria are applied in the diagnosis of primary lymphoma considering that the breast is a recognized site for disseminated extranodal lymphoma. Our case report was established by histology alone.

Aged↗
PubMed2001

The immunophenotypic profile of hepatic hemopoiesis in fetuses with Down's syndrome during the second trimester of development.

The yolk sac and aorto-gonad-mesonephros region are well recognized as the principal sites of hematopoiesis in the developing embryo, and the liver is the principal site of hematopoiesis in the fetus. In the present study, we investigated the immunohistochemical expression of Glycophorin C (erythrocytes), Neutrophilic elastase (granulocytes), and CD34 (progenitor hematopoietic stem cells, progenitor stromal cells, and vascular endothelial cells) in hepatic parenchyma from fetuses with Down's syndrome (DS) (16th, 20th, and 24th week of gestational age), and correlated the findings with the equivalent of the hepatic parenchyma from fetuses after spontaneous abortion. Our results did not demonstrate a quantitative difference at the level of erythropoiesis in all three periods examined. In contrast, an important numerical difference was shown in the expression of CD34 positive cells in liver parenchyma from fetuses with DS, in comparison with those found in liver parenchyma from fetuses after spontaneous abortion (p < 0.02). Furthermore, a modest but significant difference was demonstrated at the level of granulopoiesis between the 20th and 24th week (p < 0.01). Given that, the living newborns with Down's syndrome manifest diverse haematological abnormalities, including a transient leukemoid reaction that usually disappears after some weeks or months, a significantly increased number of CD34 positive and a less significantly increased number of neutrophilic elastase positive cells between the 20th and 24th gestational week could explain this phenomenon in combination with the respective results, if any, in the bone marrow. Regarding our finding of increased stromal CD34 positive cells in the hepatic portal triads, it raises the possibility that a process similar to fibrosis of the bone marrow may contribute to the hepatic fibrosis in DS.

Antigens, CD34↗
PubMed2001

Differential expression of Bcl-2 proto-oncogene in the trophoblast from embryos with Down's syndrome and those after spontaneous abortion.

Down's syndrome (trisomy 21) was the first human chromosomal syndrome to be recognized (in 1959 by Lejeune and colleagues). It is also the most frequent chromosomal aberration occurring in one out of 700 live newborns. In the present study we investigated the immunohistochemical expression of the apoptosis-suppressing protein Bcl-2 in placental trophoblastic cells from embryos with Down's syndrome (gestational age 12th, 15th and 22nd week) and correlated the findings with equivalent trophoblastic cells from embryos after spontaneous abortion. In our cases with Down's syndrome a weak Bcl-2 expression was noted in the cytotrophoblast and syncytiotrophoblast of chorionic villi in contrast to strong Bcl-2 staining of the same cells in the cases of spontaneous abortions (p < 0.0001). Although there are no specific findings that truly characterize a placenta with trisomy, obtaining a small piece of chorionic villus tissue (chorionic villus biopsy) and immunohistochemical control for Bcl-2 protein could be an additional prenatal examination available to the perinatologist to detect chromosomal abnormalities.

Abortion, Spontaneous↗
PubMed2001

Expression of fibrillar proteins and vimentin in developing chorionic villi is related to fetal maturation.

Using an immunocytochemical technique, the extracellular matrix components fibronectin, vimentin, laminin and collagen type IV were investigated in human chorionic villi of various stages of development. Fibronectin and laminin were consistently positive throughout embryonic development. Vimentin and collagen type IV were negative in first and second trimester chorionic villi, but became positive in term placentas. With the exception of laminin, all extracellular matrix molecules were detected in the villous stroma and, with the exception of vimentin, they were localized in the basement membranes. Our data suggest that fibronectin and laminin are essential components of the villous structure, while the presence of vimentin and collagen type IV in the chorionic villi should be regarded as an indicator of fetal maturation.

Chorionic Villi↗
PubMed2001

Imprint cytology of non-specific granulomatous mastitis.

Non-specific granulomatous mastitis (NSGM) is a tumor-like inflammatory condition involving breast lobules. Its recognition is of great significance because of clinical masquerade to invasive carcinoma. A 25-year-old woman developed a palpable breast lump with clinical and mammographic findings suggestive of malignancy. Touch imprint cytology of the excised lump was consistent with a granulomatous inflammation while histopathological examination documented a NSGM with central necrosis. Clinical, radiologic and laboratory testing failed to identify any specific causative agent.

Adult↗
PubMed2001

Expression of laminin, type IV collagen and fibronectin molecules is related to embryonal skin and epidermal appendage morphogenesis.

Basement membrane zones are specialized sheets--like arrangements of extracellular matrix proteins and glycosaminoglycans, and act as an interface between parenchymal cells and support tissue. They separate epithelium, endothelium, muscle cells and Schwann cells from adjacent connective tissue stroma, and also from a limiting membrane in the central nervous system. They are involved in several cellular and biological processes, including adhesion, migration and cellular differentiation. Basement membranes have five major components: collagen type IV, laminin, heparan sulfate, entactin, and fibronectin. In addition, there are numerous minor and poorly characterized protein and glycosaminoglycan components. The various components of the basement membranes of the skin (collagen type IV, proteoglycans--heparan sulfate, laminin, entactin and fibronectin) are products of the epithelial (epidermal) cells. We studied immunohistochemically the origin, the first appearance and distribution of the adhesive extracellular glycoprotein laminin and the fibrillar proteins of the extracellular matrix collagen type IV and fibronectin in the basement membranes of fetal human skin between 12 to 21 weeks of gestational age. Additionally, we studied the expression of vimentin in the extracellular matrix of the epithelial/mesenchyme junction of the skin. This study demonstrates clearly that the expression of the antigens laminin, collagen type IV and fibronectin starts in the germinative epithelial cells of the skin at the bulbs of the hair follicles (12th week for fibronectin and 19th week for laminin and collagen type IV), and migrating progressively involves the epithelial epidermal cells of the covering skin, as well as, the basement membrane at the dermal-epidermal junction in that region (between 20 to 21 weeks of gestational age).

Collagen Type IV↗
PubMed2001

Expression of the intermediate filament vimentin and fibrillar proteins of the extracellular matrix related to embryonal heart development.

During organogenesis, the heart is one the first organs to develop and the earliest organ to function. The early appearance of cardiac activity in the tubular hearts of chick and rat embryos was noted many years ago. It arises from two plates of the splanchnic mesoderm which fuse to form a single tubular structure composed of endocardial and myocardial cells and, between them, the extracellular cardiac matrix. There is considerable variation in the formation of the extracellular matrix in the various regions of the heart during development. The endocardial lining cells of the vertebrate embryos show a regional specificity that remains an unexplained phenomenon in cardiac morphogenesis. The great majority of the endocardial lining cells remain epithlial. However, a restricted population of endothelial cells, lining the atrioventricular (AV) canal and the reputed proximal outflow tract (OT), transforms into mesenchyme; the latter being the reputed progenitor of the valves and membranous septa. The purpose of this study was to investigate the extracellular cardiac matrix of the human fetal heart in different regions and in various stages of development, and also the heterogeneity of the endocardial cell lining, in connection with the endothelial cells of other cardiac vessels. Identification of the mesenchymal cells/extracellular matrix was confirmed by immunohistochemical techniques using the following monoclonal antibodies: actin, desmin, vimentin, collagen IV and fibronectin. The present results provide evidence that the extracellular matrix of the heart is of mesodermal origin but at the level of the valves the mesenchyme is derived from the endothelial lining cells rather than the primitive mesenchyme.

Antibodies, Monoclonal↗
PubMed2001

Marginal-zone B-cell lymphoma, extranodal-malt-type: report of three cases.

A high proportion of extranodal lymphoid infiltrates are diffuse small lymphocytic proliferations [1, 2] and therefore pose a particularly challenging diagnostic problem [1-4]. Their benign or malignant nature cannot be determined using clinical and radiologic criteria. The application of traditional morphologic criteria (i.e., cytologic maturity and polymorphism favor benignancy, while cytologic atypia and monomorphism favor malignancy) [5, 6], has probably improved diagnostic accuracy. However, these criteria generally have not been helpful in evaluating the large number of lymphoid infiltrates composed of monomorphic collections of small cytologically-mature appearing lymphoid cells [1-4] and, therefore, have not always accurately predicted clinical behavior. Extranodal lymphoid proliferations are also of considerable biologic interest since their pathogenesis and natural history have not been fully elucidated. Localized non-Hodgkin's lymphoma, extranodal-MALT-type. was diagnosed in our Department in three cases: Two arose in the orbit and the third one in the tonsil. The tumors had a typical histologic appearance. The microscopical features and immunohistochemical profile are discussed.

Aged↗
PubMed2001

Human decidual cells can express the Hodgkin's cell-associated antigen Ki-1 (CD30) in spontaneous abortions during the first trimester of gestation.

CD30 (Ki-1) antigen has been considered to be expressed on hematopoietic cells including the ones of the recently described anaplastic large cell lymphoma (ALCL), the Reed-Sternberg (RS) cells of Hodgkin's disease and the scattered large parafollicular cells in normal lymphoid tissues. Since then, several reports have been published describing CD30 expression in non-hematopoietic and malignant cells, such as cultivated human macrophages, human decidual cells, histiocytic neoplastic cells, mesothelioma cells, embryonal carcinoma, and seminoma cells. In the present study, we investigated the immunohistochemical expression of CD30 antigen in 15 paraffin-embedded placentas from fetuses after spontaneous abortion in the first trimester of gestation (8th, 10th, and 12th week, respectively) using the monoclonal antibody Ber-H2. All the pregnant patients had been given hormonal medication to support gestation. In addition, a panel of monoclonal antibodies for the identification of leukocytes (CD45/LCA), B-lymphocytes (CD20/L-26), and T-lymphocytes (CD45RO/UCHLI) was performed. Our findings were correlated with those found in 15 placentas obtained from 15 fetuses at the same time, after therapeutic or voluntary abortions. This study demonstrates that, 1) decidual endometrial stromal cells are able to express the CD30 (Ki-1) antigen, 2) the expression of CD30 in decidual cells is higher in cases of hormonal administration (to support gestation), than that found in normal gestation. In the former cases (hormonal support of gestation), a mild mononuclear infiltration of the decidua by UCHLI (T marker) positive cells, accompanies the CD30 positive cells.

Abortion, Spontaneous↗
PubMed2001

K statistic as a measure of quality control in cervicovaginal cytology.

Quality assessment schemes are widespread in most branches of pathology but are uncommon in the more subjective areas of histopathology and cytology. Researchers in many fields have become increasingly aware of the observer as an important source of measurement error. The validity of any method of reporting evidence of an abnormal process in cellular material is based on the degree of correlation with the actual disease process as it exists in the tissue and its reproducibility. Correlations can be tested in retrospective studies in which diagnoses based on cellular evidence are matched against the disease process present in biopsy specimens. Correlations can also be tested by examination of a set of unknown cellular preparations obtained in the presence of proven disease. While reproducibility is indirectly related to correlation, it is meant to imply satisfactory utilization of the method by other groups of cytotechnologists and cytopathologists. While cytopathology will continue to play an important role as a screening technique for the detection of cancer of the uterine cervix, its usefulness in the study of the early manifestations of the disease process is yet to be realized on a universal basis.

Cervix Uteri↗