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At least 541 records · Page 30Linked to original sources
PubMed1992

Estrogen and progesterone receptor detection in archival formalin-fixed, paraffin-embedded tissue from breast carcinoma: a comparison of immunohistochemistry with the dextran-coated charcoal assay.

The steroid receptor (estrogen (ER) and progesterone receptor (PR] status was studied in 94 cases of invasive breast carcinoma from three separate institutions. All cases had fresh tissue examined for ER and PR by the dextran-coated charcoal cytosolic assay (DCC), and each case was examined immunohistochemically for ER and PR from archival formalin-fixed, paraffin-embedded tissue. Immunohistochemical assays (IH) were reviewed blinded to the DCC results and scored in a semiquantitative fashion prior to comparison to the DCC results. Overall, there was agreement between DCC and IH in 89% of ER and in 87% of PR assays. Some 50% of the ER discorrelations were of the IH-positive DCC-negative type, while 27% of the PR discorrelations were of this type. In four cases, both ER and PR did not correlate between IH and DCC determinations, with two being IH (ER and PR) positive and DCC negative, and two of the opposite type. The results of the study show that steroid receptor assays performed on routinely processed formalin-fixed archival material are reliable and closely recapitulate the results of traditional biochemical assays. Results suggest that, in the cases where IH is positive while DCC is negative, the IH result may actually provide a more reliable receptor status of the tumor than does the DCC result. Semiquantitation of fixed tissue IH assays shows a trend toward quantitative correlation with DCC results, but this correlation is weak, and factors concerning fixation and processing are most likely to be responsible.(ABSTRACT TRUNCATED AT 250 WORDS)

Breast Neoplasms↗
PubMed2005

PCR based identification and discrimination of agents of mucormycosis and aspergillosis in paraffin wax embedded tissue.

BACKGROUND: Invasive fungal infections are often diagnosed by histopathology without identification of the causative fungi, which show significantly different antifungal susceptibilities. AIMS: To establish and evaluate a system of two seminested polymerase chain reaction (PCR) assays to identify and discriminate between agents of aspergillosis and mucormycosis in paraffin wax embedded tissue samples. METHODS: DNA of 52 blinded samples from five different centres was extracted and used as a template in two PCR assays targeting the mitochondrial aspergillosis DNA and the 18S ribosomal DNA of zygomycetes. RESULTS: Specific fungal DNA was identified in 27 of 44 samples in accordance with a histopathological diagnosis of zygomycosis or aspergillosis, respectively. Aspergillus fumigatus DNA was amplified from one specimen of zygomycosis (diagnosed by histopathology). In four of 16 PCR negative samples no human DNA was amplified, possibly as a result of the destruction of DNA before paraffin wax embedding. In addition, eight samples from clinically suspected fungal infections (without histopathological proof) were examined. The two PCR assays detected a concomitant infection with Absidia corymbifera and A fumigatus in one, and infections with Rhizopus arrhizus and A fumigatus in another two cases. CONCLUSIONS: The two seminested PCR assays described here can support a histopathological diagnosis of mucormycosis or aspergillosis, and can identify the infective agent, thereby optimising antifungal treatment.

Aspergillosis↗
PubMed2004

Detection of West Nile virus using formalin fixed paraffin embedded tissues in crows and horses: quantification of viral transcripts by real-time RT-PCR.

West Nile virus (WNV) RNA was quantified in WNV infected crows and horses with the help of a real-time reverse transcriptase-PCR assay. A 5' nuclease assay, based on NS5 gene detection with a fluorescent probe was used for quantifying WNV RNA using formalin fixed paraffin embedded tissue specimens. Quantitative detection of WNV RNA showed the presence of a higher amount of the viral RNA in crow tissues compared to equine tissues and these results correlated well with the detection of WNV antigen by immunostaining. In crows, the highest amount of virus was seen in the intestine and in horses in the brain.

Animals↗
PubMed1999

Frequent expression of haemopoietic and non-haemopoietic antigens by reactive plasma cells: an immunohistochemical study using formalin-fixed, paraffin-embedded tissue.

Unlike other B cells, plasma cells (PC) react with only a few antibodies against haemopoietic antigens. We investigated 36 specimens exhibiting a reactive increase in PC numbers (i.e. plasmacytosis, PC hyperplasia) with a broad panel of antibodies suitable for use on formalin-fixed, paraffin-embedded tissue, and compared the findings with those obtained in 51 cases of multiple myeloma (plasmacytoma). Regardless of the immunostaining pattern for immunoglobulin light and heavy chains, reactive PC reacted with at least two and at most six of seventeen antibodies detecting haemopoietic antigens [Ber-H2/CD30 (91%), anti-leucocyte common antigen (LCA)/CD45 (86%), KP1/CD68 (64%), MB2 (57%), 4KB5/CD45RA (37%), DF-T1/CD43 (28%), UCHL1/CD45RO (20%), L26/CD20 (17%), MT2 (14%) and Mac387 (8%)], and with at least one and at most four of six antibodies against non-haemopoietic antigens [anti-epithelial membrane antigen (EMA) (94%), anti-vimentin (77%), anti-pan-cytokeratin/KL1 (74%), BMA120 (51%) and HMB45 (14%)]. Five antibodies stained reactive PC significantly more often than neoplastic PC: Ber-H2/CD30 (p < or = 0.0000), KP1/CD68 (p < or = 0.0000), anti-LCA/CD45 (p < or = 0.0000), anti-EMA (p < or = 0.0339) and anti-pancytokeratin/KL1 (p < or = 0.0000). The more frequent and more heterogeneous expression of antigens by reactive PC suggests that the aberrant immunoreactivity of neoplastic PC in plasmacytoma is not due to the process of malignant transformation in an early step of B-cell differentiation, but could reflect the heterogeneity of antigen expression by normal PC.

Fixatives↗
PubMed2000

Clonality analysis of defined cell populations in paraffin-embedded tissue sections by RT-PCR amplification of X-linked G6PD gene.

This paper establishes a method of clonality analysis using the reverse transcription-polymerase chain reaction (RT-PCR) to amplify X-linked G6PD transcripts on defined cell populations microdissected from archival, paraffin-embedded tissue sections. Four known monoclonal low-grade B-cell lymphomas from females who were heterozygous (informative) at the 1131 exonic polymorphic locus of the G6PD gene were used to validate the method. Lymphoma and reactive lesions in each case were separated by microdissection. In order to preserve the intact RNA species in the lesion, sections were digested on the slides before microdissection. A one-step RT-PCR was performed with a single pair of primers, one of which contained a mismatched base adjacent to the polymorphic site, to generate a PvuI cutting site. Successful amplification and allele identification by PvuI digestion were achieved from all RNA samples studied. Three of four samples from non-neoplastic reactive lesions showed two bands with equal intensity, representing transcription of the two alleles of the G6PD gene, while the corresponding tumour samples demonstrated a biased intensity in one allele, indicating monoclonality. To assess the method further, the clonal nature of in situ and invasive breast cancers was examined, along with adjacent normal breast tissue and hyperplastic lesions from three informative females from our archives. Apart from the clusters of normal terminal duct-lobular units, all lesions were monoclonal. This result is in agreement with data derived from other X-linked gene studies and loss of heterozygosity (LOH) analyses of pre-invasive breast disease. The results suggest that the clonality analysis method presented here is simple and reliable, and is therefore potentially applicable in a wide range of pathological conditions.

Breast↗
PubMed1994

Quality control considerations for Ki-67 detection and quantitation in paraffin-embedded tissue.

Proliferative activity has prognostic significance in many solid tumors. Immunohistochemical analysis of tumor proliferation may be accomplished with the Ki-67 monoclonal antibody which recognizes a nuclear antigen expressed throughout the cell cycle. This antibody, however, cannot be used with formalin-fixed, paraffin-embedded tissue. Recently, a Ki-67 equivalent murine monoclonal antibody (MIB-a; AMAC, Inc., Westbrook, ME) was generated which can detect tumor proliferative activity in routinely processed tissue with microwave oven heating. Using quantiative image analysis, we assessed the effect of delay in fixation, total time of formalin fixation, and microwave heating time on the immunoreactivity of this antibody. The effect of time to fixation (0, 2, 4, 8, or 24 hours) on MIB-1 immunostaining was determined in various tumor tissues using image analysis. No significant difference in positive nuclear area was observed for tissues in which fixation was delayed for as long as 8 hours relative to controls. A 24-hour fixation delay resulted in a small decrease in positive nuclear area was observed for tissues in which fixation was delayed for as long as 8 hours relative to controls. A 24-hour fixation delay resulted in a small decrease in positive nuclear area relative to controls. The effect of fixation time (4, 24, or 48 hours) and microwave oven heating time on MIB-1 immunostaining was studied in tonsil tissue, and quantitated by image analysis. Good MIB-1 immunostaining was observed for all microwave oven heating times in tissue fixed for 4 hours.(ABSTRACT TRUNCATED AT 250 WORDS)

Antibodies, Monoclonal↗
PubMed2001

Unlocking the archive--gene expression in paraffin-embedded tissue.

The histopathology archive represents a vast, well-characterized source of specimens covering virtually every disease and is available for molecular biological investigation. The archive has in recent years become widely used for molecular genetic analysis and DNA can be routinely extracted from formalin-fixed, paraffin-embedded tissue. More recently, archival specimens have become a source of material for extensive analysis of mRNA expression utilizing DNA microarrays, real-time quantitative reverse transcriptase polymerase chain reaction (PCR), and in situ hybridization and amplification techniques. These techniques will enable a greater understanding of the changes that occur in gene function during every stage of the development of disease and will lead to better diagnosis, better evaluation of prognosis, and better treatment through targeted therapeutic regimes.

Biological Specimen Banks↗
PubMed2000

Detection of the ETV6-NTRK3 chimeric RNA of infantile fibrosarcoma/cellular congenital mesoblastic nephroma in paraffin-embedded tissue: application to challenging pediatric renal stromal tumors.

We report the development of a reverse transcriptase polymerase chain reaction assay that reliably detects the ETV6-NTRK3 chimeric RNA characteristic of infantile fibrosarcoma and the cellular variant of congenital mesoblastic nephroma (CMN) in formalin-fixed, paraffin-embedded tissue blocks. The 188 base pair polymerase chain reaction fusion product was detected in 11 of 12 cases of cellular CMN from which a larger sized control RNA band could be amplified, and even in 7 of 8 cases in which the control band was not detectable. A variety of other tumors that are in the histologic differential diagnosis of cellular CMN yielded negative results, including four classic CMNs, four rhabdoid tumors of the kidney, and four clear cell sarcomas of the kidney, confirming the assay's specificity. We further demonstrate the assay's utility by illustrating two cases of molecularly confirmed cellular CMN that mimicked rhabdoid tumor and clear cell sarcoma of the kidney. In contrast to previous reports, five mixed CMNs that had both classic and cellular areas all lacked the ETV6-NTRK3 fusion transcript. These results suggest that cases morphologically defined as mixed CMN may represent a mixed group of genetically distinct entities.

Artificial Gene Fusion↗
PubMed1990

Analysis of leukocyte surface antigens on ethanol-fixed paraffin-embedded tissue material.

Ethanol-fixed paraffin-embedded specimens of human tissues were studied whether the surface antigens of leukocytes in these tissues can be stained and analyzed. Three-layer indirect immunoperoxidase staining was performed on the ethanol-fixed paraffin-embedded sections by the use of several monoclonal antibodies for whole human leukocytes (Dako LC), B cells (Dako CD-22, 4KB5, and L26; Leu 14), T cells and their subsets (Dako UCHL-1, T1, T3, T4 and T8; Leu 4, 3a and 2a) and monocyte/macrophage lineage (Dako macrophage, Leu M1, M3 and M5). The results were compared with those on fresh-frozen sections. No essential differences were obtained between the paraffin-embedded and the fresh frozen sections stained by the following antibodies; Dako LC for whole human leukocytes; Dako UCHL-1, T3 and Leu 4 for T cells; Dako CD22, 4KB5, L26 and Leu 14 for B cells; Dako macrophage, Leu M1 and M5 for monocyte/macrophage lineage. On the other hand, the subsets of T cells could only be detected on the fresh-frozen sections. The results of the leukocyte analysis on the paraffin-embedded specimens of several renal diseases were very similar to those reported by other investigators on fresh-frozen sections or PLP-fixed materials. Thus, by the use of appropriate monoclonal antibodies, the ethanol-fixed paraffin-embedded material can be used for leukocyte analysis except for the definition of T cell subsets.

Antibodies, Monoclonal↗
PubMed1998

Polymerase chain reaction diagnosis of t(14;18) from paraffin-embedded tissues fixed with Holland Bouin fluid.

The t(14;18) translocation and its molecular counterpart, the bcl-2/IgH gene rearrangement, are highly characteristic of follicular non-Hodgkin lymphomas. The identification of the tumor-specific t(14;18) clone is mandatory for any molecular studies on residual disease because of the existence of circulating t(14;18)-bearing benign cells. In this study, the ability to specifically polymerase chain reaction (PCR) amplify t(14;18) with DNA purified from tissues fixed with Holland Bouin fluid is demonstrated. The specificity of the PCR product was confirmed by internal probe hybridization and with comparison of the nucleotidic sequences of this PCR product with those obtained from the corresponding frozen material. Although the sensitivity of the technique is 50% to 60%, paraffin-embedded tissues fixed with bouin fluid may be a good alternative to frozen tissues to detect t(14;18) in tumors.

Base Sequence↗
PubMed1991

Application of DNA flow cytometry from paraffin-embedded tissue to the diagnosis of mycosis fungoides.

The distinction of mycosis fungoides from benign inflammatory lesions is sometimes difficult by conventional histological techniques. Aneuploidy, a feature often associated with malignant tumors, can be assessed even in tissue routinely processed in paraffin using the flow cytometric technique of Hedley and associates. In many tumor systems, there are significant diploid clones. We have evaluated the flow cytometric DNA ploidy of paraffin-embedded tissue in the diagnosis and prognosis of mycosis fungoides (MF). We studied 22 cases of MF and 10 control cases of inflammatory skin lesions with epidermal involvement. Aneuploidy was found in 27% of the MF cases, but in none of the controls (ED). Aneuploid features were seen in 23% of tissues from early stage disease. Aneuploidy did not correlate with atypia, epidermotropism, or number of mitoses. There was a trend towards showing adverse outcome in those patients with aneuploid lesions. The detection of aneuploidy might be helpful for early diagnosis of MF.

Aneuploidy↗
PubMed1995

Evaluation of Ki-67 reactivity in neuroblastoma using paraffin embedded tissue.

AIMS: To examine the pattern of reactivity of Ki-67 in neuroblastoma and correlate this with a) clinical prognostic criteria and b) cell cycle statistics (using flow cytometry). METHODS: Four micron sections of paraffin embedded (PE) tissue from 55 patients (25 pre chemotherapy and 30 post) were placed on to aminosialinised slides, dewaxed and rehydrated. Slides were pretreated in a microwave oven, endogenous peroxidase activity blocked using 3% hydrogen peroxide and Ki-67 reactivity investigated using a streptavidin/biotin/peroxidase technique. DNA ploidy was also performed from an immediately adjacent section on the same block using a FACScan and Cellfit software. RESULTS: Ki-67 reactivity was well defined and highly reproducible. Eighteen out of 30 post chemotherapy samples were totally negative, despite evidence of proliferation on flow cytometry and all subsequently died of disease. As interpretation post chemotherapy was therefore deemed unreliable, this group was excluded from analysis. Reactivity in pretreatment samples ranged from 0% to 67%; staining was restricted to the nucleus with a distinct pattern noted in the nucleolus. Ki-67 positivity was lower in aneuploid compared with diploid tumours (mean 26% vs 36%, NS). Among diploid tumours, a lower percentage positivity was noted in those patients with better clinical prognostic parameters. Correlation however between Ki-67 and SG2M phases of cell cycle was poor (RS = 0.39, NS). CONCLUSION: Assessment of proliferation in neuroblastoma by Ki-67 reactivity in paraffin embedded tissue is reliable in pretreatment samples and can be incorporated into routine immunohistochemical evaluation. Larger multicentre studies are required to further evaluate Ki-67 reactivity as a prognostic indicator.

Biomarkers, Tumor↗
PubMed1992

Monoclonal and polyclonal antibodies for immunohistochemical detection of bovine parainfluenza type 3 virus in frozen and formalin-fixed paraffin-embedded tissues.

Accurate identification of bovine parainfluenza type 3 virus in bovine respiratory disease requires dependable, sensitive, and specific techniques for detection in affected animals. Immunohistochemical testing can be a rapid and reliable means of demonstration of virus in tissues from suspect cases; however, this procedure is dependent upon the quality of the antisera directed against the viral antigens. The production of rabbit polyclonal and murine monoclonal antibodies directed against bovine parainfluenza type 3 virus and techniques for their use in fresh-frozen and formalin-fixed paraffin-embedded tissues in immunofluorescence and immunoperoxidase-based immunohistochemical tests are described.

Animals↗
PubMed2001

Evaluation of crystals in formalin-fixed, paraffin-embedded tissue sections for the differential diagnosis of pseudogout, gout, and tumoral calcinosis.

Hematoxylin-eosin (H&E)-stained sections may not allow proper evaluation of birefringence properties of the crystals in the lesions of pseudogout, gout, and tumoral calcinosis. This study was undertaken to verify the application of a special stain that could facilitate the evaluation of the birefringence properties of these crystals for definitive diagnosis. We evaluated previously described nonaqueous alcoholic eosin staining (NAES) method based on the principle of using alcoholic eosin without hematoxylin and any other aqueous reagents for staining of formalin-fixed, paraffin-embedded tissue sections. Two observers, in a blinded fashion, evaluated the sections stained with routine H&E and NEAS method without the knowledge about clinical diagnosis. All pseudogout (nine sections from seven cases) and gout (eight sections from five cases) lesions demonstrated birefringence in the sections stained with NAES method. H&E-stained sections showing the respective diagnostic histomorphology failed to demonstrate the birefringent crystals by polarizing microscopy in all the eight sections from gout and in seven of nine sections from pseudogout. Only two H&E-stained sections showed scant calcium pyrophosphate dihydrate (CPPD) crystals in pseudogout. None of the three sections from two cases of tumoral calcinosis showed birefringence with either stain. We conclude that CPPD in pseudogout and monosodium urate in gout may not polarize in the routine H&E-stained sections. However, polarizing microscopy of sections stained with NAES method allowed demonstration of CPPD crystals with positive birefringence in pseudogout, MSU crystals with negative birefringence in gout, and calcium hydroxyapatite crystals without birefringence in tumoral calcinosis. Section stained with NAES method is a significantly useful adjunct to the routine H&E stain for proper evaluation of the crystals under polarizing microscope in these lesions.

Calcinosis↗
PubMed1998

Immunohistochemical detection of the human major vault protein LRP with two monoclonal antibodies in formalin-fixed, paraffin-embedded tissues.

Multidrug resistant cancer cells frequently overexpress the 110-kd lung resistance-related protein (LRP) as detected with the monoclonal antibody (MAb) LRP-56. Recently, we identified LRP as the major vault protein (MVP), which is the major constituent of vaults, multisubunit cellular organelles. Clinically, LRP/MVP expression in cancer at time of diagnosis provided a strong and independent prognostic factor for response to chemotherapy and outcome in different tumor types, notably acute myeloid leukemia and ovarian cancer. To facilitate additional immunohistopathological studies, we have optimized LRP/MVP detection in paraffin-embedded tissues using two monoclonal antibodies, LRP-56 and LMR-5. Blocking experiments showed that LRP-56 and LMR-5 MAbs detect different epitopes of LRP/MVP. Immunohistochemical studies with both MAbs in a panel of human multidrug resistant tumor cell lines, normal tissues, and colorectal tumors showed that LRP/MVP expression can be reliably detected after formalin-fixation and paraffm-embedding using overnight incubation at 4 degrees C with the primary MAbs at 5- to 10-fold higher concentrations (ie, 1 to 10 microg/ml) as currently used with frozen sections. Both streptavidin-biotin complex and alkaline phosphatase-anti-alkaline phosphatase techniques could be successfully used for signal-amplification. Staining quality did not benefit from antigen-retrieval pretreatments. The optimized staining methodology facilitates studies in archival material on the putative role of LRP/MVP in clinical drug resistance.

Antibodies, Monoclonal↗
PubMed1996

Cytokeratin labeling of breast cancer cells extracted from paraffin-embedded tissue for bivariate flow cytometric analysis.

Flow cytometric analyses of DNA content and proliferative fractions have been found to be important prognostic indicators in a variety of human tumors. However, variability in reported results and interlaboratory differences in single-parameter DNA measurements have impeded the broader use of this methodology. Multiparameter DNA analysis, especially that which allows the ploidy and cell cycle measurements to be targeted specifically to tumor cells, may improve the quality and reliability of these measurements. Cytokeratin labeling simultaneously with DNA allows the identification of the malignant epithelial cells within tumor samples that have been microdissected for tumor enrichment and, thus, can increase the accuracy of tumor ploidy and cell cycle measurements. There are a limited number of reports of cytokeratin labeling of paraffin-extracted cells, and results with standard preparation procedures can be highly variable. We have developed an improved technique for cytokeratin labeling of paraffin-extracted cells that is based on predigestion of tissue with collagenase prior to brief pepsin digestion. This two-step enzymatic digestion produces a superior cytokeratin vs. DNA bivariate analysis, with increased intensity and greater uniformity of cytokeratin labeling. This method should increase the accuracy of ploidy and proliferation measurements from paraffin-embedded tissue both for retrospective studies and in clinical settings in which only fixed tissue is available.

Aneuploidy↗
PubMed1988

Flow cytometric analysis of DNA ploidy level in paraffin-embedded tissue of non-small-cell lung cancer.

Investigations regarding the prognostic value of DNA content (ploidy) and proliferative characteristics [percentage of cells in S-phase or S-phase fraction (SPF)] have been greatly facilitated by the application of flow cytometry (FCM) using nuclei isolated from paraffin-embedded tissue. We have applied this technique to tumor sections from patients presenting with non-small-cell lung cancer (NSCLC) in 1980 and 1981. From 67 out of 115 patients material of sufficient quantity and quality was obtained to perform DNA-FCM. A multivariate analysis including stage of disease (UICC), age, tumor histology and treatment modality was performed to examine the prognostic significance of DNA-FCM in NSCLC. Aneuploidy was found in 65% of cases. In our study, the DNA content was not related to histology, stage of disease or treatment modality, nor to the length of survival (log rank test P = 0.62). Calculation of SPF was possible in 49/67 cases. The SPF was not related to histology, stage of disease or treatment modality, but a significant prognostic value was found for survival; patients with a high SPF died earlier (P = 0.04) and this was especially true for squamous cell carcinoma (P = 0.02). This study demonstrates the prognostic importance of DNA-FCM-derived information in NSCLC using a multivariate analysis; however further prospective studies in larger patient populations are needed.

Adenocarcinoma↗