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The prognostic value of immunohistochemical estrogen receptor analysis in paraffin-embedded and frozen sections versus that of steroid-binding assays.

Estrogen receptors (ER) were independently analyzed using dextran-coated charcoal assays (ER-DCC) and immunohistochemical assays in frozen (ER-ICA) and paraffin-embedded tissue (ER-PAR) from 130 human breast cancer specimens drawn from postmenopausal high-risk patients registered in the Danish Breast Cancer Cooperative Group. ER was best detected with the ER-DCC assay followed by the ER-ICA (relative sensitivity 87%) and the ER-PAR assays (relative sensitivity 71%). The semiquantified staining features of the immunohistochemical assays were statistically significantly correlated with each other and with ER-DCC. Analysis of disease-free interval (DFI) and overall survival (OS) showed that all assays allowed statistically significant discrimination between a high risk and a low risk group, although the sensitivity differences tended to be reflected as small differences in clinical discriminatory power. The patient groups were then stratified according to adjuvant treatment [radiotherapy (RT) versus radiotherapy and tamoxifen (RT + TAM)]. The survival advantage was tied primarily to the receptor status itself in the steroid-binding assays, but was linked to both the receptor status and the adjuvant treatment in the immunohistochemical assays. Thus, the relative risks in terms of DFI and OS were of the same relative magnitude in the RT and RT + TAM groups for ER-DCC assays using a cut-off level of 10 fmol/mg cytosol protein, while there were large differences in the relative risks between RT and RT + TAM groups for ER-ICA and ER-PAR assays. We conclude that an ER assay in fresh tissue should be given first priority, but if there is no fresh tissue, an ER assay in paraffin-embedded tissue offers a reasonably good alternative as a prognosticator and an equivalent alternative as a predictor of the response to endocrine treatment.

Breast Neoplasms↗

Genetic analysis of HER-2/neu gene amplification in paraffin embedded tumour tissue in women with breast cancer.

In recent years several novel prognostic determinants of breast cancer have been identified, including HER-2/neu. The oncogene called HER-2/neu or c-erbB-2 located at 17q21 encodes a 185-kD transmembrane glycoprotein, p185. The HER-2/neu gene is frequently overexpressed in human breast cancers as a result of gene amplification and/or elevated transcription. In this study we investigated the association between the presence of HER-2/neu gene ampliflcation and appearance and/or progression of breast cancer. Paraffin embedded tumour tissue was obtained from 82 women with breast cancer. Blood samples from age matched healthy women served as control (n = 50). The amplification of HER-2/neu gene was determined by PCR amplification using appropriate primers. The amplification of HER-2/neu gene was significantly higher in women with breast cancer as compared with control (P < 0.05). Additionally, there were differences in the amplification status between node-positive and node-negative breast cancer patients. The results suggest that the presence of amplification of HER-2/neu gene may be linked with the appearance and/or progression of breast cancer.

Adult↗

Retrospective diagnosis of trisomy 15 in formalin-fixed, paraffin-embedded placental tissue in a newborn girl with Prader-Willi syndrome.

Paternal deletion of 15q11-q13 and maternal uniparental disomy (UPD) of chromosome 15 are the main causes of Prader-Willi syndrome (PWS). The finding of an UPD(15) is associated with increased maternal age. We present a retrospective diagnosis of a trisomy 15 mosaicism confined to the placenta (CPM) after birth of a girl with clinical features of PWS born to a 43-year-old mother. Chromosome analysis after amniocentesis, performed because of advanced maternal age, had shown a normal female karyotype. In peripheral blood cells molecular studies showed the absence of the paternal allele at the SNRPN locus and fluorescence in situ hybridization (FISH) analysis excluded a deletion of the SNRPN locus on both chromosomes 15. Trisomic cells were detected by FISH on nuclei isolated from formalin-fixed, paraffin-embedded placental tissue using a DNA-probe specific for the centromeric region of chromosome 15.

Adult↗

New aspects in the histological examination of polyethylene wear particles in failed total joint replacements.

The most important long-term complication in total joint replacements is aseptic osteolysis. Wear particles such as polyethylene (PE) debris are considered to be one of the causes that play a central role. Several studies indicated that PE can be visualised in paraffin-embedded tissue sections not only by polarised light, but also after oil red staining. To determine whether oil red staining enables sensitive detection of PE, we examined staining of mechanically-produced PE particles by oil red. Furthermore, we studied oil red staining of paraffin-embedded tissue specimens of patients with failed uncemented and cemented total knee and hip prostheses. We applied double labelling of sections by immunohistochemistry using the macrophage marker anti-CD68 and oil red staining. We found that oil red stains both isolated PE particles and PE particles in paraffin-embedded tissue sections. Polymethylmethacrylate particles in failed cemented arthroplasties did not stain in paraffin sections. Double labelling showed strong colocalisation of CD68 and PE. We suggest that oil red staining is a sensitive method to detect PE particles. Oil red staining is particularly helpful in these cases which show a characteristic histological feature of aseptic prosthesis loosening without particles being detectable with routine microscopy and polarised light. We also established that immunohistochemical methods can be applied together with the oil red staining method.

Antigens, CD↗

Immunohistochemical detection of DNA topoisomerase I in formalin fixed, paraffin wax embedded normal tissues and in ovarian carcinomas.

AIMS: To determine, by in situ immunohistochemistry, whether ovarian carcinomas have increased expression of DNA topoisomerase I. METHODS: Paraffin wax blocks obtained from 15 samples of normal human tissues and from 14 cases of ovarian cancer were cut on to glass slides and immunohistochemically stained for topoisomerase I. The primary antibody was a mouse monoclonal that recognises topoisomerase I in western blots. Colour was detected using a peroxidase system with diaminobenzidine as the chromogen. The expression of topoisomerase I in the tissues and tumours was graded subjectively from 0 to 3+ based on the colour intensity of the immunostain. RESULTS: In normal tissues, topoisomerase I expression was strongest in the mucosal lymphocytes in the gastrointestinal tract and in the germinal centres of the tonsil. Weak topoisomerase I staining was found in the columnar epithelium of the gastrointestinal tract and in squamous mucosa. In the series of ovarian carcinomas, raised topoisomerase I was observed in 43% (6 of 14) of the tumours. Of the tumours with raised topoisomerase I, only three contained a population of rapidly cycling cells. Therefore, 21% of our series of ovarian carcinomas (3 of 14) had raised topoisomerase I expression and were proliferating rapidly. CONCLUSIONS: Topoisomerase I expression in formalin fixed, paraffin wax embedded human tissues can be evaluated by immunohistochemical staining. Increases in topoisomerase I occur in some cases of ovarian cancer.

Blotting, Western↗

Prognostic role of a multigene reverse transcriptase-PCR assay in patients with node-negative breast cancer not receiving adjuvant systemic therapy.

PURPOSE: To test the ability of a reverse transcriptase-PCR (RT-PCR) assay, based on gene expression profiles, to accurately determine the risk of recurrence in patients with node-negative breast cancer who did not receive systemic therapy using formalin-fixed, paraffin-embedded tissue. A secondary objective was to determine whether the quantitative RT-PCR data correlated with immunohistochemistry assay data regarding estrogen receptor, progesterone receptor, and human epidermal growth factor receptor 2 status. PATIENTS AND METHODS: We obtained archival paraffin-embedded tissue from patients with invasive breast cancer but no axillary lymph node involvement who had received no adjuvant systemic therapy and been followed for at least 5 years. RNA was extracted from three 10-microm-thick sections. The expression of 16 cancer-related genes and 5 reference genes was quantified using RT-PCR. A gene expression algorithm was used to calculate a recurrence score for each patient. We then assessed the ability of the test to accurately predict distant recurrence-free survival in this population. RESULTS: We identified 149 eligible patients. Median age at diagnosis was 59 years; mean tumor diameter was 2 cm; and 69% of tumors were estrogen receptor positive. Median follow-up was 18 years. The 5-year disease-free survival rate for the group was 80%. The 21 gene-based recurrence score was not predictive of distant disease recurrence. However, a high concordance between RT-PCR and immunohistochemical assays for estrogen receptor, progesterone receptor, and human epidermal growth factor receptor 2 status was noted. CONCLUSIONS: RT-PCR can be done on paraffin-embedded tissue to validate the large numbers of genes associated with breast cancer recurrence. However, further work needs to be done to develop an assay to identify the likelihood of recurrent disease in patients with node-negative breast cancer who do not receive adjuvant tamoxifen or chemotherapy.

Adult↗

AgNOR staining of cell imprint preparations of human bladder cancer.

OBJECTIVE: To determine the clinical usefulness of argyrophilic nuclear organizer region (AgNOR) staining as applied to cell imprint preparations in bladder cancer. STUDY DESIGN: The study group consisted of 59 bladder cancers (13 grade 1, 24 grade 2 and 22 grade 3). The staining time, quality of staining, relationship of AgNOR counts to tumor grade and interobserver variations in AgNOR counts were compared in cell imprint preparations and paraffin-embedded tissue sections. Interobserver variation was compared by calculating the coefficients of variation (CVs) and correlation coefficients between two independent observers. RESULTS: Following an optimal staining time of 30 minutes, the AgNOR dots of cell imprint preparations were highly distinct. In contrast, the optimal staining time was variable, and the AgNOR dots often were observed to aggregate in paraffin-embedded tissue sections. The mean AgNOR count was significantly higher in imprint preparations. AgNOR counts from the imprint preparations showed a stronger relationship to tumor grade. The CVs of AgNOR scores in the cell imprints was significantly smaller, and the correlation coefficient was significantly greater. CONCLUSION: AgNOR staining of cell imprint preparations is a more objective method than paraffin-embedded tissue sections in human bladder cancer.

Coloring Agents↗

Clinical utility of heteroduplex analysis of TCR gamma gene rearrangements in the diagnosis of T-cell lymphoproliferative disorders.

We conducted this study to assess the clinical utility of heteroduplex analysis of polymerase chain reaction (PCR) products for Tgamma gene rearrangements in the diagnosis of T-cell lymphoproliferative disorders (LPDs) using a single set of consensus primers. This method was used to study 103 cases using fresh or frozen tissue. These included 62 cases of T-cell LPDs, 25 cases of B-cell LPDs, 3 cases of anaplastic large cell lymphomas of undefined lineage, and 13 cases of reactive disorders. The latter group served as the negative control group. For all cases of T-cell LPDs, the results of Tbeta Southern analysis (SA) and heteroduplex PCR analysis were compared. We also studied 10 cases of postthymic T-cell lymphoma using paraffin-embedded tissue. Heteroduplex Tgamma PCR was positive in 51 (89%) of 57 cases that were rearranged by Tbeta SA. Eight of the 10 cases of T-cell lymphoma analyzed using paraffin-embedded tissue were positive. There were no false-positive results. These results demonstrate that this method is an effective screening test in the clinical laboratory. A positive result obviates the need to perform SA. Preliminary results suggest this method is useful using paraffin-embedded tissue.

Base Sequence↗

Quantitative and morphological aspects of Unicryl versus Lowicryl K4M embedding in immunoelectron microscopic studies.

In this study we compared the recently commercialized electron microscopy embedding resin Unicryl with the well-known resin Lowicryl K4M with regard to morphological and immunohistochemical preservation properties. The standard embedding procedure recommended by the manufacturer for the use of Unicryl resulted in considerable morphological alterations of the tissue, with the appearance of large gaps in and between the cells of the examined tissue. Morphometric analysis pointed to a swelling of the extracellular matrix as the main cause of these morphological artifacts. A slight modification in the protocol to correct this artifact is proposed and tested. Immunohistochemically, tissue embedded in Unicryl resulted in a significantly stronger immunogold labeling than identical tissue embedded in Lowicryl K4M. From the results of this technical study, it can be concluded that Unicryl embedding is a valuable new tool to supplement the available techniques for immunoelectron microscopic studies.

Acrylic Resins↗

Expression analysis of mRNA in formalin-fixed, paraffin-embedded archival tissues by mRNA in situ hybridization.

Gene expression in diseased tissues can indicate the contribution to a disease process and potentially guide therapeutic decision-making. Archival tissues with associated clinical outcome may be useful to discover or validate the role of a candidate gene in a disease process or the response to therapy. Such archival tissues are commonly formalin-fixed and paraffin-embedded, restricting the methods available for gene expression analysis. Obviously, the detection of proteins in tissues requires adaptation for each protein and the detection of secreted proteins can prove difficult or of reduced value since the protein detected may not reflect the total amount produced. Thus, we describe here a reliable method for the detection of mRNA in archival tissues. The method for mRNA in situ hybridization (ISH) was adapted by us for >15 different genes and applied to several hundred tissue microarrays (TMAs) and full sections generating >10,000 expression data points. We also discuss the utility of TMAs to simultaneously analyze several hundred tissue samples on one slide to minimize variability and preserve valuable tissue samples. Experimental protocols are provided that can be implemented without major hurdles in a typical molecular pathology laboratory and we discuss quantitative analysis as well as advantages and limitations of ISH with a special focus on secreted proteins. We conclude that ISH is a reliable and cost effective approach to gene expression analysis in archival tissues that is amenable to screening of series of tissues or of genes of interest.

Animals↗

Highly sensitive immunohistological study for detection of estrogen receptor in human breast cancer.

BACKGROUND: Immunohistological methods for the detection of estrogen receptor in human breast cancer using formalin-fixed, paraffin-embedded tissue not only have the advantages of being cheaper and requiring less tissue but also have several theoretical advantages. For example, such methods enable direct histological visualization of the assessed tissue and thereby reduce sampling error. Traditional immunohistological methods (traditional LSAB), however, show false-negative reactions more often than the enzyme-binding immunoassay method (EIA). METHODS: After determining 25 estrogen receptor-positive cases and 50 estrogen receptor-negative cases by EIA, we analyzed these same cases using a traditional LSAB method and a new highly sensitive immunohistological method for assaying formalin-fixed, paraffin-embedded tissue. RESULTS: Using this new method, we detected 10 instances of positive estrogen receptors among the 50 EIA receptor-negative cases. The 25 EIA-positive cases were positive for estrogen receptor antigen except 1case using the new method. CONCLUSIONS: This new method not only has the advantage of use in paraffin-embedded tissue but also is more sensitive than the EIA. We recommend this new method as a choice to decrease false-negatives.

Adult↗

SEM of human and experimental renal disease.

This review concerns the present state of accomplishments in the study of SEM of human and experimental renal disease. Critical techniques of specimen preparation reviewed include perfusion fixation, razor tissue sectioning, alcohol cryofracture, microtome sectioning of paraffin or styrene embedded tissue, ultraplaning with glass knives of hard carbowax embedded tissues and glomerular isolation. Gold-palladium coating and heavy metal impregnation with osmium, uranium, and silver are discussed. A compendium of SEM observations of human glomerular, vascular and tubular disease is presented. Techniques for SEM of experimental renal disease are reviewed. These include latex vascular injection, freeze drying, x-ray microanalysis and use of backscattered electron imaging. Experimental models previously investigated by SEM are puromycin aminonucleoside nephrosis, daunomycin nephrosis, and N,N1-Diacetylbenzedine glomerulopathy, nephrotoxic serum nephritis, and protamine perfusion glomerulopathy. Reviewed are acute tubular necrosis caused either by angiotensin, hypotension, norepinephrine, glycerol, mercury, and unilateral renal artery occlusion, also potassium depletion nephropathy, alloxan diabetes and diphenylamine-induced polycystic disease.

Acute Kidney Injury↗

Utility of CD15, CD30 & CD45 in the immunohistochemical diagnosis of Hodgkin's disease by antigen retrieval method.

The utility of staining Reed-Sternberg (RS) cells with CD30, CD15 and CD45 as a diagnostic aid in Hodgkin's disease (HD) and the value of microwave citrate antigen retrieval (AR) method in improving the results of immunohistochemical (IHC) studies were evaluated. Histological and immunohistological studies were carried out on 21 patients with HD seen from January 1987 to December 1996 in the Pathology Department of the Cumhuriyet University, School of Medicine. Avidin biotin peroxidase complex (ABC) was used in IHC study as a method for detection of RS cells. Monoclonal antibodies CD30, CD15 and CD45 were applied on formalin fixed paraffin embedded tissue sections. In order to enhance the immunoreactivity, microwave citrate AR method and proteolytic pretreatment were used. The reactivity of RS cells and staining patterns were determined. In 14 (70%) of the 20 patients, RS cells stained positively with CD30, in 16 (80%) CD15 staining was positive and only 1 (5%) was positively stained with CD45. A combination of cytoplasmic with cell surface staining was common with CD30, while paranuclear deposit with cell surface and cytoplasmic staining was common with CD15. In conclusion, to facilitate the detection of RS cells in formalin fixed paraffin embedded tissues, the application of a panel of markers appears to be necessary. Also AR method seems to be helpful in obtaining optimal results on formalin fixed paraffin embedded tissue.

Hodgkin Disease↗

Immunohistochemical double staining of microwave enhanced and nonenhanced nuclear and cytoplasmic antigens.

Many of the antigens commonly investigated in histopathology can be enhanced by microwave pretreatment (MWPT) of formalin fixed, paraffin embedded tissue sections. We developed a double labeling method using microwave heating to detect otherwise undetectable nuclear antigens combined with immunohistochemistry (IHC) of cytoplasmic or membranous antigens that do not benefit from MWPT. We used the same primary antibody solutions used in single antibody IHC. The staining technique is based on the alkaline phosphatase anti-alkaline phosphatase (APAAP) and the labeled avidin-biotin (LSAB) methods. Four different protocols were tested, each modifying the sequence of MWPT, APAAP and LSAB staining. In this study Ki67, estrogen receptor, progesterone receptor, c-neu, CD68 and desmin primary antibodies were used in routinely formalin fixed, paraffin embedded tissues of 50 tumor specimens. MWPT followed by LSAB for microwave enhanced antigens and APAAP for antigens that cannot be enhanced by MWPT gave the best double staining results. This method improves characterization of tumor cell features from paraffin embedded tissue and should aid analysis of tumor differentiation, receptor status and nuclear proteins in the single cells in archival tissues.

Antigens, Neoplasm↗

Immunofluorescent staining of plastic-embedded renal tissue.

Human renal tissues were fixed in cold 4% paraformaldehyde and 0.2% picric acid, embedded in glycol methacrylate (GM), and sectioned at a thickness of 1 to 8 micrograms. Sections were incubated for three hours with nonspecific protease, stained with fluorescein isothiocyanate-conjugated goat antihuman serum samples, and examined by immunofluorescent microscopy. The immunofluorescent staining was compared with that in cryostat sections of the same tissues prepared and stained by conventional methods. The GM-embedded sections showed consistent staining of antigens, comparable with that in the corresponding cryostat sections, and better preservation of tissue structure than in cryostat sections. The antigens in tissues processed by this method are probably stable for long periods.

Antigens↗

Identification of leucocyte surface antigens in paraffin-embedded bovine tissues using a modified formalin dichromate fixation.

A modified fixative of formalin dichromate was combined with a cold embedding procedure for the preservation of bovine leucocyte surface antigens. Fourteen monoclonal antibodies recognizing seven bovine leucocyte surface antigens (BoCD1w2, BoCD4, BoCD8, BoWC1, BoWC3, BoWC4 and BoIgM) were applied as primary antisera in a sensitive avidin-biotin-peroxidase complex detection method. The staining results were compared with those obtained in cryostat and routinely formalin-fixed sections of corresponding tissue samples. Using the modified formalin dichromate fixative and the cold embedding procedure, all the leucocyte surface antigens tested were detectable immunohistologically in paraffin sections with a generally more distinct staining than in traditionally processed tissues. Morphological structures were better preserved than in cryostat sections but, to some extent, were poorer when compared with routinely formalinfixed tissues. However, this method suggests that there are only mild masking effects and provides an alternative to the use of unfixed material, particularly for morphological-immunohistochemical investigations.

Animals↗

Different assays for HER-2/neu evaluation in breast cancer.

To evaluate different methodologic approaches for HER-2/neu analysis, we performed Southern, Northern, Western blot and histochemical assay on 112 samples from 86 primary tumors and 26 synchronous axillary metastatic lymph nodes of patients affected by operable breast cancer. Simultaneous statistical analysis of data obtained with the four methods (31 samples) showed that Western blot detected a higher percentage of alterations than the other assays (Cochran and Victor tests, 0.01 less than p less than 0.05). The same result was emphasized by pair analysis (McNemar, p less than 0.05), which evaluated the assay data two by two. Immunohistochemical evaluations were more in accord with immunoprecipitation data when performed on frozen or Bouin-fixed, paraffin-embedded tissues than on formalin-fixed, paraffin-embedded tissues.

Blotting, Northern↗

Histochemical identification of human T lymphocytes from paraffin sections.

The alpha-naphthyl acetate esterase (ANEA) is a histochemical marker for human T lymphocytes in cell smears and frozen tissue sections. We have now applied the ANAE method to paraffin-embedded tissue sections. We first demonstrated with cytocentrifuged cell smears of blood leukocytes that the ANAE activity is preserved upon prolonged storage in formol calcium, Holt's buffer, acetone, xylene, and heat. When the tissue sections were similarly processed and embedded in paraffin, the ANAE positive (T) lymphocytes were identified by their distinct display of one or more reddish-brown reaction dots in the cell cytoplasm. ANAE positive mononuclear phagocytes were easioy distinguished from the T lymphocytes by their diffuse, sodium fluoride-sensitive pancytoplasmic reaction. The extension of the ANAE method to paraffin-embedded tissue sections with superior morphological integrity, makes it possible to apply it in practical biopsy pathology.

Biopsy↗