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Cytoplasmic Staining (cytoplasmic + staining)
Selected AbstractsPlant profilin isovariants are distinctly regulated in vegetative and reproductive tissuesCYTOSKELETON, Issue 1 2002Muthugapatti K. Kandasamy Abstract Profilin is a low-molecular weight, actin monomer-binding protein that regulates the organization of actin cytoskeleton in eukaryotes, including higher plants. Unlike the simple human or yeast systems, the model plant Arabidopsis has an ancient and highly divergent multi-gene family encoding five distinct profilin isovariants. Here we compare and characterize the regulation of these profilins in different organs and during microspore development using isovariant-specific monoclonal antibodies. We show that PRF1, PRF2, and PRF3 are constitutive, being strongly expressed in all vegetative tissues at various stages of development. These profilin isovariants are also predominant in ovules and microspores at the early stages of microsporogenesis. In contrast, PRF4 and PRF5 are late pollen-specific and are not detectable in other cell types of the plant body including microspores and root hairs. Immunocytochemical studies at the subcellular level reveal that both the constitutive and pollen-specific profilins are abundant in the cytoplasm. In vegetative cell types, such as root apical cells, profilins showed localization to nuclei in addition to the cytoplasmic staining. The functional diversity of profilin isovariants is discussed in light of their spatio-temporal regulation during vegetative development, pollen maturation, and pollen tube growth. Cell Motil. Cytoskeleton 52:22,32, 2002. © 2002 Wiley-Liss, Inc. [source] The effects of antibody clone and pretreatment method on the results of HER2 immunostaining in cytologic samples of metastatic breast cancer: A query and a review of the literature,,§DIAGNOSTIC CYTOPATHOLOGY, Issue 6 2007Patricia A. Fetsch M.T. (ASCP) Abstract The standardization and use of heat-induced epitope retrieval (HIER) is particularly important with immunohistochemical markers that direct the course of cancer treatment, such as Herceptin therapy. Increasingly, many laboratories are performing immunohistochemical analysis using various antibodies and methodologies for HER2/neu. We attempted to determine the effects of antibody clone and pretreatment methods on the interpretation of HER-2/neu staining in cytologic samples. Cell block sections from 54 cases of metastatic breast cancer (24 FNAs, 30 effusions) were analyzed for HER2 expression using antibodies to CB-11, TAB250, and A0485. Antibodies were analyzed with and without HIER. One pathologist using the FDA-approved scoring system for the HercepTest reviewed all slides in a blinded fashion. Five of fifty-four cases (9%) using CB-11 showed a significant increase in HER2 immunoreactivity using HIER (i.e. from 0/1+ to 2,3+). However, in twenty-nine of fifty-four cases (54%), the cytoplasmic background was significantly higher after HIER. With the A0485 antibody, two of fifty four cases (4%) showed a significant increase in immunoreactivity using HIER, while seventeen of fifty-four cases (31%) exhibited only more pronounced cytoplasmic staining. HIER pretreatment did not increase HER2 staining in any TAB250 stained sample, rather four of fifty-four cases (7%) showed a significant decrease in staining with HIER. We conclude that HIER may enhance membrane staining with the CB-11 and A0485 antibodies, but also increases cytoplasmic background. Loss of antigenicity is seen when HIER is used with TAB250. Diagn. Cytopathol. 2007;35:319,328. © 2007 Wiley-Liss, Inc. [source] Comparison of antibodies to HBME-1 and calretinin for the detection of mesothelial cells in effusion cytology ,DIAGNOSTIC CYTOPATHOLOGY, Issue 3 2001Patricia A. Fetsch M.T. (A.S.C.P.) Abstract The distinction of mesothelial cells in cytologic samples is often a diagnostic challenge. This is particularly true in potentially malignant effusions in which reactive mesothelial cells may simulate adenocarcinoma (ACA) cells, and in the differentiation of ACA vs. mesothelioma. We sought to determine the superior antibody for the positive identification of mesothelial cells in these circumstances. Cell block sections of 25 reactive and 8 malignant mesothelioma effusions were immunostained with an avidin-biotin procedure, using antibodies to HBME-1 and calretinin. No pretreatment of samples was necessary for the HBME-1-stained slides; microwave antigen retrieval was performed on all slides stained for calretinin. A negative control was performed on each sample. The staining intensity of tumor cells was scored on a scale of 0,3+, with the proportion of immunoreactive cells categorized as <25%, 25,50%, 50,75%, and >75%. The predominant staining pattern for HBME-1 was surface, with rare samples also exhibiting cytoplasmic staining as well. The calretinin-staining pattern was cytoplasmic, with peripheral condensation/prominence and accompanying nuclear staining. All samples were immunoreactive with both antibodies. Fifty-five percent (18/33) of samples showed significantly stronger immunoreactivity with calretinin than with HBME-1; 45% (15/33) of samples showed equivalent staining with the two markers. None of the samples in this study showed stronger immunoreactivity with HBME-1 than with calretinin. Sixty-one percent (20/33) of samples stained with HBME-1 at a moderate (2+) intensity. Fifty-five percent (18/33) of samples stained with calretinin at a strong (3+) intensity. While only 12% of samples showed >75% immunoreactivity for HBME-1, 58% of samples showed >75% of cells immunoreactive for calretinin. Calretinin is the preferred marker in identifying mesothelial cells in cytologic samples, showing the highest sensitivity for mesothelial cells, as evidenced by a more intense staining reaction in a higher percentage of cells than with HBME-1. Diagn. Cytopathol. 2001;25:158,161. Published 2001 Wiley-Liss, Inc. [source] AN ENDOCRINE CELL CARCINOMA WITH GASTRIC-AND-INTESTINAL MIXED PHENOTYPE ADENOCARCINOMA COMPONENT IN THE STOMACHDIGESTIVE ENDOSCOPY, Issue 4 2009Tsutomu Mizoshita A 77-year-old man complained of bodyweight loss, and a Borrmann 3 type lesion was observed endoscopically in the anterior wall of angular region of the stomach. The endocrine cell carcinoma (ECC) having the cytoplasmic staining of chromogranin A (CgA) was detected pathologically in the biopsy samples. The patient underwent distal gastrectomy plus systemic lymph node (LN) dissection (D2 LN dissection), and pathological examination revealed ECC invading the subserosa, and no LN metastasis (pT2N0M0). None of the gastric and intestinal endocrine cell marker expression was apparent in the ECC cells. The lesion also contained a moderately differentiated type tubular adenocarcinoma component, which was judged to be gastric-and-intestinal mixed (GI type) phenotype, using gastric and intestinal exocrine cell markers. After the surgery, he left the hospital and started oral doxifluridine (600 mg/day). The patient now (March 2008, about 19 months since the surgery) continues this chemotherapy with no recurrence. In conclusion, we experienced ECC with a GI type adenocarcinoma component. The ECC cases with the GI type adenocarcinoma component may have a relatively good prognosis, being similar to the results of advanced gastric cancers from the viewpoint of gastric and intestinal phenotypic expression. [source] Immunohistochemical study of epidermal growth factor receptor in adenoid cystic carcinoma of salivary gland originHEAD & NECK: JOURNAL FOR THE SCIENCES & SPECIALTIES OF THE HEAD AND NECK, Issue 7 2002Marilena Vered DMD Abstract Background Epidermal growth factor (EGF) and its receptor (EGFR) are involved in the development of salivary gland tumors. Recently, treatment modalities for EGFR inhibition have shown an enhanced clinical response in carcinomas of different locations. Adenoid cystic carcinoma (ACC) of salivary gland origin is a malignant tumor with a poor long-term outcome. If salivary gland ACC does exhibit EGFR, then immunotherapy could have a major impact on improving its prognosis. Methods The study consisted of 34 samples of formalin-fixed, paraffin-embedded specimens of salivary gland ACC. Specimens were stained with a mouse antihuman monoclonal antibody for immunohistochemical detection of EGFR. Overlying oral mucosa and adjacent normal salivary ducts served as internal controls. Both membrane and cytoplasmic staining were evaluated. Staining score was calculated by multiplying the percentage of positively stained tumor cells by the intensity of the staining. The highest score for a given tumor was equal to 2. Results In the final analysis, 27 of the 34 specimens were included; 7 were excluded, because the internal control did not reveal any staining. Of these 27 specimens, 23 (85%) stained positively for EGFR with a staining score of 0.05 to 1.8. Three palatal tumors attained the highest scores (one tumor, 1.2, and the remaining two, 1.8). Conclusions Most salivary gland ACC stained positively for EGFR, and in some the staining was quite intense. On the basis of the already proven antitumoral effect of agents acting as EGFR inhibitors, it is suggested that patients with ACC might benefit from these agents, especially when surgery has failed or in those with recurrent or metastatic disease. © 2002 Wiley Periodicals, Inc. Head Neck 24: 632,636, 2002 [source] Trafficking and localization of platinum complexes in cisplatin-resistant cell lines monitored by fluorescence-labeled platinum,JOURNAL OF CELLULAR PHYSIOLOGY, Issue 3 2005Xing-Jie Liang Cisplatin is a chemotherapeutic agent commonly used in the treatment of a wide variety of malignant tumors. Resistance to cisplatin represents a major obstacle to effective cancer therapy because clinically significant levels of resistance quickly emerge after treatment. Based on previous studies indicating abnormal plasma membrane protein trafficking in cisplatin-resistant (CP-r) cells, Fluorescence (Alexa Fluor)-labeled cisplatin was used to determine whether this defect altered the trafficking and localization of cisplatin by comparing drug sensitive KB-3-1 and KB-CP-r cells. Alexa Fluor,cisplatin was readily internalized and localized throughout the KB-3-1 cells, but overall fluorescence decreased in KB-CP-r cells, as detected by flow cytometry (FACS) and confocal microscopy. Only punctate cytoplasmic staining was observed in KB-CP-r cells with less fluorescence observed in the nucleus. Colocalization experiments with a Golgi-selective stain indicate the involvement of Golgi-like vesicles in initial intracellular processing of Alexa Fluor conjugated cisplatin complexes. As detected using an antibody to Alexa Fluor,cisplatin, cisplatin complex-binding proteins (CCBPs) were reduced in membrane fractions of single-step cisplatin-resistant KB-CP.5 cells, and increased in the cytoplasm of KB-CP.5 cells compared to KB-3-1 cells. CCBPs localized to lower density fractions in KB-CP.5 cells than in KB-3-1 cells as determined by iodixanol gradient centrifugation. In summary, inappropriate trafficking of CCBPs might explain resistance to cisplatin in cultured cancer cells, presumably because membrane binding proteins for cisplatin are not properly located on the cell surface in these cells, but are instead trapped in low density vesicles within the cytoplasm. © 2004 Wiley-Liss, Inc. [source] Immunohistochemical expression of RANKL, RANK, and OPG in human oral squamous cell carcinomaJOURNAL OF ORAL PATHOLOGY & MEDICINE, Issue 10 2009Fu-Hsiung Chuang Background:, The mechanism of oral squamous cell carcinoma (SCC) invading jawbone remains controversial. Interactions between receptor activator of NF-,B (RANK) and its ligand (RANKL) are required for osteoclastogenesis. The binding of RANK and RANKL induces differentiation of osteoclasts, leading to bony destruction. Osteoprotegerin (OPG), a decoy receptor for RANKL, also binds to RANKL by competing with RANK, and this could protect against osseous destruction. Materials and methods:, Immunoexpression of RANKL, RANK, and OPG in 25 cases of human buccal SCCs without bony invasion and 15 cases of gingival SCCs with mandibular bony invasion was investigated. Normal oral mucosa from five individuals without betel-quid chewing or cigarette smoking was used as a control. The scores are designated as percentage of positive staining × intensity of staining for each section. Results:, Strong cytoplasmic staining of RANKL proteins is detected in cancer cells of both buccal and gingival SCCs. The same protein is identified in cytoplasm of osteoclasts for all cases involving bony invasion. Strong cytoplasmic staining of RANKL is confined to basal layer for all normal mucosa. A similar staining pattern is noted for RANK protein in all buccal and gingival SCCs. An absence of staining of RANK protein is noted for all normal tissues. Weak to negative cytoplasmic stained OPG protein is present in all buccal and gingival SCCs, but is absent in all normal tissues. Conclusion:, These findings suggest the potential value of the RANK/RANKL/OPG pathway as biomarkers in human oral SCCs. [source] J1-31 protein expression in astrocytes and astrocytomasNEUROPATHOLOGY, Issue 5 2009Shanop Shuangshoti J1-31 is one of the astrocytic proteins, the expression of which has not been evaluated in astrocytomas. In the present study, we studied the expression of J1-31 protein in astrocytes and astrocytomas in comparison with GFAP, p53 and Ki-67. Materials consisted of formalin-fixed paraffin-embedded tissue specimens that included five cases of normal brain, 17 of gliosis, 15 of pilocytic astrocytoma (WHO grade I), 26 of low-grade diffuse astrocytoma (WHO grade II), four of anaplastic astrocytoma (WHO grade III), and eight of glioblastoma (WHO grade IV). GFAP was highly expressed in all specimens examined. The anti-J1-31 antibody exhibited strong cytoplasmic staining of reactive gliosis in 17/17 (100%) cases with a higher intensity of staining than that observed in the adjacent normal astrocytes. The antibody showed reactivity with tumor cells in 12/15 (80%) cases of pilocytic astrocytoma, although intensity of staining was generally weaker and more focal than observed in reactive gliosis. J1-31-positive tumor cells were detected in only 9/26 (35%) cases of the low-grade diffuse astrocytoma and none of the cases of anaplastic astrocytoma and glioblastoma. Increasing Ki-67 indices paralleled advancing tumor grades. p53 protein was expressed more commonly in infiltrating astrocytomas compared to pilocytic astrocytoma. In conclusion, down-regulation of J1-31 expression correlates with advancing grade of astrocytomas. The result suggests this protein plays some role in astrocytes that is progressively lost in malignant progression. The anti-J1-31 antibody may help further our understanding of astrocytes in disease and may be useful as an aid in the pathologic diagnosis of astrocytic lesions. [source] Nestin expression as a new marker in malignant peripheral nerve sheath tumorsPATHOLOGY INTERNATIONAL, Issue 2 2007Satoko Shimada Malignant peripheral nerve sheath tumor (MPNST) can be difficult to diagnose because it lacks specific immunohistochemical markers. S-100, which is a useful marker of MPNST, has limited diagnostic utility. Recent studies suggest that nestin, which is an intermediate filament protein, is expressed in neuroectodermal stem cells. The diagnostic utility of immunostains for nestin and three other neural markers (S-100, CD56 and protein gene product 9.5 (PGP 9.5)) were evaluated in 35 cases of MPNST and in other spindle cell tumors. All MPNST cases were strongly positive for nestin and had cytoplasmic staining. Stains for S-100, CD56, and PGP 9.5 were positive in fewer cases (17/35, 11/35, and 29/35 cases, respectively), and had less extensive staining. Nestin was negative in 10/10 leiomyomas, and weak nestin expression was seen in 10/10 schwannomas, 3/10 neurofibromas, 2/8 synovial sarcomas, 2/10 liposarcomas, 4/7 carcinosarcomas and 3/7 malignant fibrous histiocytomas. In contrast, strong nestin positivity was seen in 10/10 rhabdomyosarcomas, 15/19 leiomyosarcomas, and 9/9 desmoplastic melanomas. Nestin is more sensitive for MPNST than other neural markers and immunostains for nestin in combination with other markers could be useful in the diagnosis of MPNST. [source] Beta-catenin status in paediatric medulloblastomas: correlation of immunohistochemical expression with mutational status, genetic profiles, and clinical characteristics,THE JOURNAL OF PATHOLOGY, Issue 1 2009Sarah Fattet Abstract Medulloblastoma is the most frequent malignant paediatric brain tumour. The activation of the Wnt/,-catenin pathway occurs in 10-15% of medulloblastomas and has been recently described as a marker for favourable patient outcome. We report a series of 72 paediatric medulloblastomas evaluated for ,-catenin protein expression, CTNNB1 mutations, and comparative genomic hybridization. Gene expression profiles were also available in a subset of 40 cases. Immunostaining of ,-catenin showed extensive nuclear staining (>50% of the tumour cells) in six cases and focal nuclear staining (<10% of cells) in three cases. The other cases either exhibited a signal strictly limited to the cytoplasm (58 cases) or were negative (five cases). CTNNB1 mutations were detected in all ,-catenin extensively nucleopositive cases. The expression profiles of these cases documented strong activation of the Wnt/,-catenin pathway. Remarkably, five out of these six tumours showed a complete loss of chromosome 6. In contrast, cases with focal nuclear ,-catenin staining, as well as tumours with negative or cytoplasmic staining, never demonstrated CTNNB1 mutation, Wnt/,-catenin pathway activation or chromosome 6 loss. Patients with extensive nuclear staining were significantly older at diagnosis and were in continuous complete remission after a mean follow-up of 75.7 months (range 27.5,121.2 months) from diagnosis. All three patients with focal nuclear staining of ,-catenin died within 36 months from diagnosis. Altogether, these data confirm and extend previous observations that CTNNB1 -mutated tumours represent a distinct molecular subgroup of medulloblastomas with favourable outcome, indicating that therapy de-escalation should be considered. International consensus on the definition criteria of this distinct medulloblastoma subgroup should be achieved. Copyright © 2009 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd. [source] High mobility group box chromosomal protein 1: A novel proinflammatory mediator in synovitisARTHRITIS & RHEUMATISM, Issue 10 2002R. Kokkola Objective High mobility group box chromosomal protein 1 (HMGB-1) is a ubiquitous chromatin component expressed in nucleated mammalian cells. It has recently and unexpectedly been demonstrated that stimulated live mononuclear phagocytes secrete HMGB-1, which then acts as a potent factor that causes inflammation and protease activation. Macrophages play pivotal roles in the pathogenesis of arthritis. The aim of this study was to determine whether synovial macrophage expression of HMGB-1 is altered in human and experimental synovitis. Methods Intraarticular tissue specimens were obtained from healthy Lewis rats, Lewis rats with Mycobacterium tuberculosis,induced adjuvant arthritis, and from patients with rheumatoid arthritis (RA). Specimens were immunohistochemically stained for cellular HMGB-1. Extracellular HMGB-1 levels were assessed in synovial fluid samples from RA patients by Western blotting. Results Immunostaining of specimens from normal rats showed that HMGB-1 was primarily confined to the nucleus of synoviocytes and chondrocytes, with occasional cytoplasmic staining and no extracellular matrix deposition. In contrast, inflammatory synovial tissue from rats with experimental arthritis as well as from humans with RA showed a distinctly different HMGB-1 staining pattern. Nuclear HMGB-1 expression was accompanied by a cytoplasmic staining in many mononuclear cells, with a macrophage-like appearance and an extracellular matrix deposition. Analysis of synovial fluid samples from RA patients further confirmed the extracellular presence of HMGB-1; 14 of 15 samples had HMGB-1 concentrations of 1.8,10.4 ,g/ml. Conclusion The proinflammatory mediator HMGB-1 was abundantly expressed as a nuclear, cytoplasmic, and extracellular component in synovial tissues from RA patients and from rats with experimental arthritis. These findings suggest a pathogenetic role for HMGB-1 in synovitis and indicate a new potential therapeutic target molecule. [source] Distinctive E-cadherin and epidermal growth factor receptor expression in metastatic and nonmetastatic head and neck squamous cell carcinomaCANCER, Issue 1 2008Predictive, prognostic correlation Abstract BACKGROUND. The authors investigated whether coexpression and localization of E-cadherin (E-cad) and epidermal growth factor receptor (EGFR) had predictive and/or prognostic correlations with lymph node metastasis and/or survival in patients with squamous cell carcinoma of the head and neck (SCCHN). METHODS. Immunohistochemistry (IHC) of archival tissue was performed to measure expression of EGFR and E-cad in surgical specimens of SCCHN (n = 143) that included primary tumors (PTs) with positive lymph nodes (Tu+Met) and their paired lymph node metastases (LnMet), PTs with negative lymph nodes (Tu,Met), and benign tissue biopsies as normal controls. IHC staining was quantified as a weighted index and as the ratio of membrane to cytoplasmic staining. Correlative expression between EGFR and E-cad also was examined in SCCHN cell lines by immunoblotting and immunofluorescence analyses. RESULTS. Three distinct expression patterns of EGFR and E-cad were observed. Membrane localization of E-cad was significantly lower in the Tu+Met group than in the Tu,Met group (P = .01) and was associated inversely with lymph node status (P = .009). Wilcoxon analysis of the combined markers demonstrated that expression and/or membrane localization of EGFR and E-cad were correlated with disease-free survival and overall survival in patients with SCCHN. The study of SCCHN cell lines demonstrated that cells with positive but low EGFR expression and with negative E-cad expression were relatively resistant to the EGFR tyrosine kinase inhibitor erlotinib. CONCLUSIONS. The current study suggested that examining not only the expression but also the localization of EGFR and E-cad simultaneously may have clinical relevance in predicting lymph node metastasis, patient survival, and response to EGFR-targeted therapy in patients with SCCHN. Cancer 2008. © 2008 American Cancer Society. [source] | |||||||||||||