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J Kopolovic

Publications and source records attributed to J Kopolovic.

At least 55 records · Page 3Linked to original sources
PubMed1999

Spectral morphometric characterization of breast carcinoma cells.

The spectral morphometric characteristics of standard haematoxylin and eosin breast carcinoma specimens were evaluated by light microscopy combined with a spectral imaging system. Light intensity at each wavelength in the range of 450-800 nm was recorded for 10(4) pixels from each field and represented as transmitted light spectra. A library of six characteristic spectra served to scan the cells and reconstruct new images depicting the nuclear area occupied by each spectrum. Fifteen cases of infiltrating ductal carcinoma and six cases of lobular carcinoma were examined; nine of the infiltrating ductal carcinoma and three of the lobular carcinoma showed an in situ component. The spectral morphometric analysis revealed a correlation between specific patterns of spectra and different groups of breast carcinoma cells. The most consistent result was that lobular carcinoma cells of in situ and infiltrating components from all patients showed a similar spectral pattern, whereas ductal carcinoma cells displayed spectral variety. Comparison of the in situ and the infiltrating ductal solid, cribriform and comedo carcinoma cells from the same patient revealed a strong similarity of the spectral elements and their relative distribution in the nucleus. The spectrum designated as number 5 in the library incorporated more than 40% of the nuclear area in 74.08% of the infiltrating lobular cells and in 13.64% of the infiltrating ductal carcinoma cells (P < 0.001). Spectrum number 2 appeared in all infiltrating ductal cells examined and in none of the lobular cells. These results indicate that spectrum number 5 is related to infiltrating lobular carcinoma, whereas spectrum number 2 is characteristic for infiltrating ductal carcinoma cells. Spectral similarity mapping of central necrotic regions of comedo type in situ carcinoma revealed nuclear fragmentation into defined segments composed of highly condensed chromatin. We conclude that the spectral morphometric features found for lobular and ductal cell populations may serve future automated histological diagnostics.

Breast Neoplasms↗
PubMed1999

Proliferation, apoptosis and thymic involution.

The thymus reaches its maximal size at the age of 1 month in ICR mice and thereafter, the thymic cortex undergoes an exponential decline. This study was designed to compare the proliferation and apoptosis of thymocytes in different parts of the thymus of ICR female mice at the beginning and after the rapid phase of decline of the thymic cortical cellularity. The pattern of proliferation and apoptosis of the thymus was studied in situ in 1-month-old ICR female mice (10 mice) compared to mice at 7 months of age (10 mice). Staining for argyrophylic nucleolar organizer region by histochemistry was used to determine the proportion of type 2 thymocytes, which are considered as cells at S phase of the cell cycle. The mean number of type 2 cells in four random samples of 50 cells in each part of the thymus was defined as the proliferation index of this part of the thymus. In situ detection of apoptosis of thymocytes was carried out using the Apoptag kit, which can detect a single cell apoptosis. The mean number of apoptotic cells in five randomly selected fields of each part of the thymus was defined as the apoptotic index of this part of the thymus. The proliferation index of the peripheral cortex of the 1-month-old mice was 3.6 times higher than the proliferation index of the deep cortex and 5.8 times higher than the proliferation index of the medulla (P < 0.0001). The proliferation index of the peripheral cortex of the 7-month-old mice was reduced by 45% compared to the 1-month-old mice (P < 0.005). The apoptotic index of the corticomedullary junction of the 1-month-old mice was six times higher than the apoptotic index of the cortex and 18 times higher than the apoptotic index of the medulla. The apoptotic index of the thymic cortex was elevated by 66% in the 7-month-old mice compared to the 1-month-old mice (P < 0.0001). We conclude that there is a reduction of the proliferation index and an elevation of the apoptotic index of the thymic cortex in adult mice compared to young mice. These changes might account for the reduction of thymic cortical cellularity during thymic involution.

Aging↗
PubMed1999

Expression of metalloproteinases endometrial stromal sarcoma: immunohistochemical study using image analysis.

AIM: To investigate the expression of matrix metalloproteinases (MMP), a group of proteolytic enzymes with a central role in extracellular matrix invasion and degradation, in stromal sarcomas. METHODS: 11 endometrial stromal sarcomas (four low grade tumours, seven high grade) were stained for MMP-2, MMP-3, and MMP-9 using immunohistochemical stains. The surgical material consisted of nine hysterectomy specimens and two pelvic recurrences. Three hysterectomy specimens, removed for leiomyomas, were studied as controls. Staining area was evaluated using image analysis. RESULTS: Age at the time of diagnosis ranged from 21 to 67 years. Four of the 11 patients (three with high grade tumours and one with a low grade tumour) died of the disease, six remained free of disease, and one was lost to follow up. Staining for MMP-2, MMP-3, and MMP-9 was more diffuse in high grade tumours than in low grade tumours and controls. Staining for MMP-3 and MMP-9 was more pronounced in high grade than in low grade tumours (p = 0.04; p = 0.05). Staining for MMP-9 was significantly greater in all stromal sarcomas than in controls (p < 0.001 for high grade tumours v controls; p < 0.01 for low grade tumours v controls). Diffuse staining for MMP-2, exceeding 90% of the tumour area, was observed in three of seven high grade tumours but in no low grade tumours. There was no apparent correlation between staining for any of the three enzymes and survival. CONCLUSIONS: Both low and high grade endometrial stromal tumours express matrix metalloproteinases. MMP-3 and MMP-9 are expressed more diffusely in high grade than in low grade tumours. In the individual case, diffuse staining for MMP-2 appears to best characterise the high grade tumours. Thus staining for MMP-2 may aid in differentiating high grade from low grade tumours, and MMP-9 in differentiating normal endometrial stroma from low and high grade endometrial stromal sarcomas. MMP expression does not appear to predict disease outcome in endometrial stromal sarcoma.

Adult↗
PubMed1999

Enhancement of atherosclerosis in beta-2-glycoprotein I-immunized apolipoprotein E-deficient mice.

We have previously shown that low density lipoprotein receptor-deficient (LDL-RD) mice immunized with beta2-glycoprotein I (beta2GPI; a target of autoimmune anticardiolipin antibodies) developed enhanced early atherosclerosis, when fed a normal chow diet. The current study was undertaken to evaluate the effect of immunization with beta2GPI and the addition of a high fat diet on the progression of atherosclerosis in the apolipoprotein E (ApoE)-deficient mouse. Six-week-old female ApoE-deficient mice (n = 10) were immunized subcutaneously with either human beta2GPI or with ovalbumin, both emulsified in complete Freund's adjuvant and fed a high fat diet for 6 weeks. The beta2GPI-immunized mice were found to develop accelerated atherosclerosis when compared with their ovalbumin-immunized littermates (aortic lesion area of 137,500 +/- 13,801 vs. 72,444 +/- 14,465 microm2, respectively; p = 0.0067). The beta2GPI-immunized mice developed high titers of anti-beta2GPI antibodies, 10 days after the procedure, which were sustained until the sacrifice. LDL extracted from both study groups displayed similar susceptibility to ex vivo oxidation. These results confirm our previous study in which we found increased atherosclerosis in beta2GPI-immunized LDL-RD mice fed a chow diet. In the current study we show that the proatherogenic effect of beta2GPI immunization is maintained despite high cholesterol levels and is not associated with increased susceptibility of LDL to ex vivo oxidation.

Animals↗
PubMed1999

Enhanced fatty streak formation in C57BL/6J mice by immunization with heat shock protein-65.

Recent data suggest that the immune system is involved in atherogenesis. Thus, interest has been raised as to the possible antigens that could serve as the initiators of the immune reaction. In the current work, we studied the effects of immunization with recombinant heat shock protein-65 (HSP-65) and HSP-65-rich Mycobacterium tuberculosis (MT) on early atherogenesis in C57BL/6J mice fed either a normal chow diet or a high-cholesterol diet (HCD). A rapid, cellular immune response to HSP-65 was evident in mice immunized with HSP-65 or with MT but not in the animals immunized with phosphate-buffered saline (PBS) alone. Early atherosclerosis was significantly enhanced in HCD-fed mice immunized with HSP-65 (n=10; mean aortic lesion size, 45 417+/-9258 microm2) or MT (n=15; 66 350+/-6850 microm2) compared with PBS-injected (n=10; 10 028+/-3599 microm2) or nonimmunized (n=10; 9500+/-2120 microm2) mice. No fatty streak lesions were observed in mice fed a chow diet regardless of the immunization protocol applied. Immunohistochemical analysis of atherosclerotic lesions from the HSP-65- and MT-immunized mice revealed infiltration of CD4 lymphocytes compared with the relatively lymphocyte-poor lesions in the PBS-treated or nonimmunized mice. Direct immunofluorescence analysis of lesions from HSP-65- and MT-immunized mice fed an HCD exhibited extensive deposits of immunoglobulins compared with the fatty streaks in the other study groups, consistent with the larger and more advanced lesions found in the former 2 groups. This model, which supports the involvement of HSP-65 in atherogenesis, furnishes a valuable tool to study the role of the immune system in atherogenesis.

Animals↗
PubMed1999

Increased endothelial cell expression of alpha3beta1 integrin in cardiac valvulopathy in the primary (Hughes) and secondary antiphospholipid syndrome.

The objective of this work was to determine markers of endothelial cell activation in valves from patients with antiphospholipid syndrome (APS) and heart valve involvement, in order to establish a role for endothelial cells in the pathogenesis of the valvular disease. Sixteen valves from ten patients with APS, obtained from autopsies or removed during valve replacement, were studied. Two groups of valves were used as controls. One group included seven normal valves from patients who died from non-cardiac diseases. The other group of valves were obtained from patients with bacterial endocarditis during autopsies or valve replacement operations. Immunoperoxidase and immunofluorescence stainings with antibodies to human immunoglobulins, endothelial cells, alpha3beta1 integrin, collagen IV, laminin and fibronectin were employed. Three histopathological patterns were apparent: normal valves, valves with verrucous endocarditis and valves with fibrocalcific changes. In all the valves with verrucous endocarditis the following findings were observed: (1) increased expression of the alpha3beta1 integrin on the endothelial cells, (2) increased amount of collagen IV, laminin and fibronectin, (3) proliferation of blood vessels and (4) linear subendothelial deposition of immunoglobulins and complement. The valves with fibrocalcific changes were deformed and showed a thick layer of collagen IV, laminin and fibronectin, yet in two valves the indothelial cells showed an expression of the alpha3beta1 integrin. The control valves did not express the integrin and had only a thin subendothelial band of collagen IV. In valves from patients with APS, 1 markers of endothelial cell activation are upregulated while the inflammatory exudate is scant. There is also a prominent deposition of immunoglobulins in the valves from patients with APS, suggesting a possible association between the deposition of the antibodies and the activation of the endothelial cells in APS.

Actins↗
PubMed1999

Local complement genes expression in the mammary gland: effect of gestation and inflammation.

Complement components in breast milk may enhance the local immune response in the gut of infants. In this study, we investigated the expression of complement genes in the mammary gland and attempted to determine possible regulatory mechanisms. We have studied the expression of C3, C4, factor B, and HLA-DRalpha mRNA by in situ hybridization in gestational mammary gland specimens and compared these findings to those in breast tissue affected with an inflammatory process, lactating adenoma or idiopathic gynecomastia. In normal resting breast, only C4 mRNA was noted in some ductal epithelium. In gestational mammary gland, there was a diffuse expression of C4, C3, and factor B mRNA in the epithelial cells of the acini. A similar pattern of complement gene expression was found in localized areas of an infectious inflammatory process. In addition, in the inflammatory specimens, there was also expression of C3 mRNA in infiltrating macrophages (CD 68 positive cells). In gynecomastia, C4 mRNA was noted in ductal epithelium, and there was a marked increased expression of C3 mRNA in the proliferating epithelium of the lactating adenoma. HLA-DRalpha was observed only in macrophages involved in the inflammatory response. Our findings, which reflect the hormonal and inflammatory events in vivo, provide new insights as to in situ complement gene expression.

Adenoma↗
PubMed1999

Antibodies to the cytoplasm, cell membrane and nuclear membrane of malignant neoplasms in pooled normal human polyspecific immunoglobulin G.

IVIg is a preparation of normal polyspecific IgG obtained from pooled plasma of a large number of healthy donors. IVIg treatment of patients with chronic lymphocytic leukemia induced a reduction in the total number of lymphocytes in the peripheral blood. Regression of Kaposi's sarcoma was also noted in an HIV patient treated with IVIg. The aim of this study was to determine whether F(ab')2 prepared from IVIg binds to cellular structures of different tumor tissues. Biotinylated F(ab')2 was prepared from 3 different preparations of IVIg and from affinity purified IgG from a patient with multiple myeloma. Direct immunohistochemistry using a streptavidin peroxidase staining method was performed on biopsy samples of 18 different tumor tissues. Positive staining of the cytoplasm, cell membrane and nuclear membrane of several types of malignant tumors by F(ab')2 from IVIg was immunohistochemically demonstrated. Nuclear staining of tumor cells by IVIg was rare. IVIg bound to different tumors of epithelial origin, especially colon carcinoma, breast carcinoma and squamous cell carcinoma of the lung. Malignant tumors of mesenchymal origin such as leiomyosarcoma have also demonstrated positive staining by IVIg. IVIg contains antibodies to the cytoplasm, nuclear membrane and cell membrane of different malignant tumors especially of epithelial origin. This binding might provide a basis for the assumption that IVIg treatment of cancer patients may induce antibody dependent cell mediated cytotoxicity response against tumors, and implies that it can be potentially beneficial as adjuvant treatment of malignant diseases.

Antibody Affinity↗
PubMed1999

Macrophage infiltration and angiogenesis in cervical squamous cell carcinoma--clinicopathologic correlation.

BACKGROUND: The role of angiogenesis and inflammatory cell response in predicting disease outcome was evaluated in various malignant tumors. However, the data relating to cervical cancer remains equivocal. This study evaluates the prognostic significance of microvessel counts and peritumoral macrophage infiltrates in squamous cell carcinoma of the uterine cervix. METHODS: Seventy-five cervical squamous cell carcinomas were stained immunohistochemically by two endothelial markers- anti-CD31 and Ulex Europaeus lectin I (UEA-I), and the macrophage- specific marker anti-CD68. Microvessel and macrophage counts were performed using a grid at X200 and X400 magnification, respectively, in areas of maximal density ('hot spots'). Five fields were scanned. Microvessel counts were correlated with macrophage density, and both were correlated with patient age, tumor stage, histological grade, and survival. RESULTS: Microvessel counts were comparable for ulex lectin (mean 6.8+/-4.8/field) and CD31 (8.7+/-5.3/field), and results by both markers correlated (p<0.001). Counts by both markers correlated with tumor stage, being higher in stages Ib-II compared to stage III-IV tumors (p<0.05). No correlation with age, grade, or survival was found. Macrophage counts (mean 13.1+/-12.3 cells/field) did not correlate with any of the clinical parameters studied or with microvessel counts. CONCLUSIONS: Microvessel counts and macrophage density do not correlate with survival in cervical cancer. Neither do they appear to be inter-related. The association between elevated microvessel counts and localized disease may reflect peak angiogenic stimuli by neoplastic cells. We hypothesize that the beneficial role of macrophages in cellular immunity may be opposed by the elaboration of growth factors in the vicinity of neoplastic cells.

Adult↗
PubMed1998

Induction of early atherosclerosis in LDL-receptor-deficient mice immunized with beta2-glycoprotein I.

BACKGROUND: Immunization with beta2-glycoprotein I (beta2GPI), the probable target of autoimmune anticardiolipin antibodies, results in experimental antiphospholipid syndrome in different mouse strains. The present study was undertaken to evaluate the effect of beta2GPI immunization on the progression of atherosclerosis. METHODS AND RESULTS: In the first experiment, 3 groups of LDL receptor-deficient (LDL-RD) mice (n=15 per group) were immunized with either beta2GPI or ovalbumin or were not immunized and were fed a chow diet for 12 weeks. In a second experiment, 3 groups of LDL-RD mice (n=10 per group) were immunized similarly and fed an atherogenic diet for 6 weeks. All beta2GPI-immunized mice developed high titers of anti-beta2GPI antibodies as well as a specific lymph node proliferation to beta2GPI. The average cholesterol levels did not differ between the mice fed similar diets, regardless of the immunization protocol. Atherosclerosis was enhanced in the beta2GPI-immunized mice (mean aortic lesion, 26 000+/-5700 microm2) in comparison with their ovalbumin-immunized (mean, 3000+/-1099 microm2; P<0.01) and nonimmunized (mean, 2250+/-700 microm2; P<0.01) littermates. The average lesion size in the beta2GPI-immunized mice fed an atherogenic diet (mean, 98 000+/-8305 microm2) was larger than the ovalbumin-immunized mice (mean, 81 250+/-12 933 microm2; P=NS) or the nonimmunized controls (mean, 75 625+/-7281 microm2; P=NS). The atherosclerotic plaques in the beta2GPI-immunized mice appeared to be more mature, and denser infiltration of CD4 lymphocytes was present in the subendothelium of the aortic sinuses from this group of mice. CONCLUSIONS: The results of the present study provide the first direct evidence for the proatherogenic effect of ss2GPI immunization and establish a new model for immune-mediated atherosclerosis.

Animals↗
PubMed1998

Rates of Jewish ancestral mutations in BRCA1 and BRCA2 in borderline ovarian tumors.

BACKGROUND: Germline mutations in the BRCA1 and BRCA2 genes are known to be associated with an increased risk of breast and epithelial ovarian cancers. Two specific mutations, 185delAG-BRCA1 and 6174delT-BRCA2, have been detected in a substantial proportion (20%-60%) of unselected Ashkenazi Jewish patients--i.e., Jewish patients of Eastern/Northern European descent--with invasive ovarian cancer and in a measurable proportion (2%) of the general Ashkenazi Jewish population. However, uncertainty exists concerning the heritable basis of borderline ovarian tumors and whether these tumors represent an early form of ultimately invasive disease. To gain insight into these issues, we determined the rates of 185delAG-BRCA1 and 6174delT-BRCA2 mutations in patients with borderline ovarian tumors. METHODS: Analysis of 185delAG-BRCA1 and 6174delT-BRCA2 germline mutations was performed by use of a heteroduplex formation assay in samples from 46 consecutive patients with borderline ovarian tumors and 59 consecutive patients with invasive epithelial ovarian cancers. Forty-eight samples were also analyzed by restriction enzyme analysis for the presence of the 5382insC-BRCA1 mutation, a mutation detected in 2.2% of Ashkenazi Jewish patients with breast, but not ovarian, cancer. RESULTS: One (2.2%) of the 46 patient with borderline tumors was identified as a carrier of the 185delAG-BRCA1 mutation, and no patients were found to carry the 6174delT-BRCA2 mutation. Nineteen (32%) of the 59 patients with invasive ovarian cancer were found to carry one of these two mutations; 17 carried 185delAG-BRCA1 and two carried 6174delT-BRCA2 (chi2 test with continuity correction, P = .00028). None of the patients analyzed for 5382insC-BRCA1 were found to carry the mutation. In one high-risk family that included 185delAG-BRCA1 carriers, a single patient with stage IIIc borderline ovarian tumor did not carry the mutation. CONCLUSIONS: Invasive epithelial and borderline ovarian tumors appear to differ in their genetic predisposition and in the molecular mechanisms underlying their genesis.

Female↗
PubMed1998

Borderline tumors of the ovary: fertility treatment, conservative management, and pregnancy outcome.

BACKGROUND: Ovarian tumors of borderline malignancy have a less aggressive behavior and tend to occur at a younger age than their invasive counterparts. The role and extent of fertility-sparing conservative treatments is under continuous evaluation. METHODS: The current study was a retrospective review of 82 patients with confirmed borderline tumors diagnosed over a 25-year period, with special focus on fertility-associated issues. RESULTS: Follow-up was available for 96% of the patients, for a total of 357 women-years of follow-up. Thirty-nine patients underwent conservative management. Of these, only three patients had a contralateral recurrence. Two of the three again opted for conservative management and were without evidence of disease at last follow-up. Seventeen patients did benefit from contralateral ovarian dissection either by cystectomy or oophorectomy because of contralateral benign or borderline disease. Eleven patients had received or were scheduled to receive ovulation induction. Five patients were diagnosed during the evaluation, and another two were diagnosed so soon after the initiation of ovulation induction that a causative relationship appeared to be unlikely. Six patients were diagnosed during ongoing pregnancies. Twenty-two pregnancies were achieved in 15 patients after conservative treatment. No influence of the disease or its treatment on the pregnancy (or vice versa) was observed during a mean follow-up of 69 months. CONCLUSIONS: Data are accumulating that indicate conservative fertility-sparing disease management is adequate treatment for patients with borderline tumors. Available data indicate that in these patients fertility, pregnancy outcome, and survival remain excellent.

Adenocarcinoma, Mucinous↗
PubMed1998

Malignant thymoma associated with autoimmune diseases: a retrospective study and review of the literature.

OBJECTIVES: To determine whether malignant thymoma is associated with high rates of concomitantly occurring autoimmune diseases. METHODS: Sheba Medical Center computer records from 1966 to 1995 were reviewed to identify patients with malignant thymoma, either type I (invasive thymoma) or type II (thymic carcinoma). All patients who had malignant thymoma and autoimmune phenomena were analyzed. The diagnosis of thymic neoplasm was confirmed by two independent pathologists. The diagnosis of autoimmune diseases was based on both clinical and serological findings. RESULTS: Six of 22 (27%) cases of malignant thymoma had an autoimmune disease. Five patients had type I malignant thymoma and either myasthenia gravis (four patients) or Graves' disease (one patient). Only one patient had type II malignant thymoma with Sjögren's syndrome. The diagnosis of autoimmune disease preceded the diagnosis of thymic neoplasm in four cases, and was diagnosed simultaneously in two. CONCLUSIONS: Malignant thymomas are highly associated with autoimmune diseases, as are benign thymomas. To our knowledge, we report the first documented cases of a patient with thymic carcinoma and Sjögren's syndrome, and another with invasive thymoma and Graves' disease.

Adult↗
PubMed1998

Expression of matrix proteins in uterine cervical neoplasia using immunohistochemistry.

OBJECTIVE: Neoplastic cells of various tumors are capable of modifying extracellular matrix, and can reduce basement membrane components and express matrix proteins and mRNA. Findings in cervical cancer cells have been consistent concerning their ability to reduce basement membrane, but there is a lack of consensus concerning the expression of matrix proteins in the neoplastic cells. We have investigated the expression of matrix proteins in the subepithelial basement membrane, in blood vessels and in the epithelial cells using immunohistochemistry. STUDY DESIGN: A total of 49 cases, including normal cervix, Cervical Intraepithelial Neoplastia (CIN) grades, I, II and III, and invasive squamous cell carcinoma, were stained for fibronectin (FN), laminin (LN) and collagen IV (C IV) and analyzed by immunohistochemistry. Subepithelial and peritumoral basement membrane staining for C IV was scored as 0, 1, 2 or 3 (0, absent; 1, weak and discontinuous; 2, weak or discontinuous; 3, strong and diffuse). Vascular basement membrane staining by all three markers was interpreted as positive or negative. Staining of normal epithelium, CIN lesions and invasive carcinoma cells was evaluated with all three markers. RESULTS: Subepithelial basement membrane staining was graded as score = 3 in all normal cervices, in contrast to 9/10, 2/10, 1/10 and 0/9 cases of CIN I, CIN, II, CIN III and invasive carcinoma, respectively. Remaining cases showed variable degrees of basement membrane loss. In 6/10 CIN III cases and 8/9 carcinomas, staining was absent (score = 0). Blood vessels stained positive for FN, LN and C IV in all cases studied. Epithelial cells were LN-positive in only one case of CIN II and FN-positive in only two cases of CIN III. Conversely, 3/9 carcinomas were LN-positive, 6/9 were FN-positive and 2/9 were C IV-positive, including two cases positive for all three markers. Staining pattern was cytoplasmic, mainly in the periphery to tumor islands. CONCLUSIONS: Invasive squamous cell carcinomas of the cervix are capable of expressing matrix proteins that are usually absent in normal squamous cervical cells or preinvasive lesions. Secretion or degradation of these proteins could facilitate tumor invasion of stroma and vessels. In addition, basement membrane dissolution becomes pronounced in CIN II-III lesions, being complete in most invasive carcinomas, probably reflecting the ability of pre-invasive neoplastic cells to degrade basement membrane components with metalloproteases.

Basement Membrane↗
PubMed1998

Immunohistochemical analysis of rasGTPase activating protein (rasGAP) in prostate cancer.

The ras protooncogene plays a key role in the signal transduction cascade of activated growth factors, and is known to be activated or overexpressed in multiple tumor types, including prostate cancer. rasGTPase activating protein (rasGAP), a major downregulator of ras activity, has been shown to be underexpressed in human trophoblastic tumors, and presumably acts as a tumor suppressor gene product in these neoplasms. To assess the role that rasGAP plays in the development of prostate cancer, we performed immunohistochemical analyses with anti rasGAP antibodies of 125 human prostate tumors from Israel. Staining results were correlated with Gleason grade. In the majority of tumors (99/125-79%) there was either no staining or the tumor and surrounding benign glands had a similar pattern of staining. In up to 16% of the tumors, cytoplasmic, tumor-specific loss of expression was noted, presumably indicative of the role of rasGAP as a tumor suppressor gene. Unexpectedly, in up to 21% of the tumors, nuclear staining was demonstrated, and in about 20% of these, there was an accompanying loss of expression in the non neoplastic cytoplasm. Neither cytoplasmic nor nuclear staining correlated with Gleason grade. These findings of nuclear staining by anti-rasGAP are intriguing, since it is the first time that nuclear translocation of rasGAP is demonstrated, which might indicate that in this subset of tumors, rasGAP acts as a direct acting oncogene. The data indicate that rasGAP may play a dual regulatory role in prostate proliferation and that nuclear expression of it may be associated with malignant transformation of these cells.

Adenocarcinoma↗
PubMed1998

Spectrally resolved morphometry of the nucleus in hepatocytes stained by four histological methods.

A novel concept of spectrally resolved morphometry for histological specimens was developed using light microscopy combined with spectrally resolved imaging. The spectroscopic characteristics of rat hepatocytes stained by Haematoxylin and Eosin, Romanowsky-Giemsa, periodic acid-Schiff and Masson's trichrome were assessed. Light intensity in the range 450-850 nm was recorded from 10000 pixels of nuclear domains of each stained cell and represented as light transmittance spectra and optical density. In order to identify spectral shifts caused by stain-macromolecule interactions, we compared the spectra of individual stain components with those of DNA and bovine serum albumin. Chromatin and interchromatin areas were classified spectrally using a chosen spectral library followed by morphometric calculations of nuclear domains for each staining method. The spectral fingerprints of Masson's trichrome stain distinguished the nucleolus from the rest of the nuclear chromatin, enabling the demarcation and calculation of the nucleolar area. Spectrally resolved imaging of human hepatocytes stained by Masson's trichrome stain revealed marked differences between the nucleolar area in normal human hepatocytes compared with hepatocellular carcinoma. Masson's trichrome stain also distinguished the nucleolar area in human breast carcinoma cells and keratinocytes.

Animals↗