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PubMed1992

DNA ploidy in cell nuclei from paraffin-embedded material--comparison of results from two laboratories.

In 49 pairs of contiguous sections from paraffin-embedded prostatic cancer tissue, the DNA indices (DIs) were determined by flow cytometry (FCM) at 2 different laboratories. In 3 of 45 pairs of evaluable nuclear suspensions, DIs of 1.1 (DNA aneuploid) were found at Laboratory 1, whereas all 3 tumours were classified as DNA diploid at Laboratory 2. In the remaining 42 specimens, the correlation between the DIs was excellent, though the application of strictly defined DNA ploidy ranges led to different DNA ploidy allocation in 3 cases. It is concluded that in 85-90% of the cases, reliable DIs can be obtained by FCM done in paraffin-embedded material at different laboratories. Slight technical variations and interpretation differences may lead to different ploidy allocation in 10-15% of the cases.

Aneuploidy↗

PubMed1987

Flow cytometric analysis of nuclear DNA from adrenocortical neoplasms. A retrospective study using paraffin-embedded tissue.

Nuclear DNA content of paraffin-embedded tissue from 48 adrenocortical neoplasms, 18 histologically normal control adrenal glands, and five hyperplastic adrenal glands was analyzed retrospectively using flow cytometry. Aneuploidy was compared with morphologic criteria as a predictor of recurrence. All 18 controls, five hyperplastic glands, and 39 neoplasms were diploid. Nine neoplasms were aneuploid. Compared with their diploid counterparts, aneuploid neoplasms were more likely to weigh more than 50 g (P less than 0.0001) and to have three or more histologic features of carcinoma (P less than 0.0001). Thirty-six neoplasms were followed clinically for at least 2 years (range 24 to 120 months, mean = 64.6 months) or until local recurrence, metastasis, or death. Five were clinically malignant. Neoplasms which recurred or metastasized were more apt to be aneuploid (P less than 0.005) than those showing no evidence of further disease during the follow-up period. They were also more likely to weigh more than 50 g (P less than 0.005) and to have three or more histologic features of carcinoma (P less than 0.0025). However, neither aneuploidy, large size, nor unfavorable histology result was a consistent feature in every malignant neoplasm. Flow cytometric DNA content analysis appears to be as effective a predictor of clinical outcome as size and histology and may be of particular value when the morphologic features are ambiguous.

Adenoma↗

PubMed1990

[Flow cytometric DNA analysis of papillary carcinoma of the thyroid using paraffin-embedded specimens].

A flow cytometric DNA analysis of papillary thyroid carcinomas has been performed on paraffin-embedded specimens, in order to determine the clinical usefulness of this method by defining the degree of the biological malignancy. Fifty-eight patients with papillary carcinomas were followed from 2 to 8 years. They were classified according to their prognosis into three groups: non-recurrent (47 patients), recurrent (5 patients), and a deceased group (6 patients). Aneuploidy was found in 6 (10.3%) of the total 58 patients. It was more frequently detected in the recurrent (40%) and in the deceased (33.3%) groups than in the non-recurrent group (4.3%). Higher proliferating index values were observed in the deceased group than in the recurrent and non-recurrent groups. These results indicate that a DNA analysis, using routine paraffin-embedded materials, is a useful adjunct in the determination of the degree of the biological malignancy of a papillary carcinoma.

Adult↗

PubMed2004

HSP47 is a useful marker for skin fibroblasts in formalin-fixed, paraffin-embedded tissue specimens.

AIM: This study was undertaken to assess whether heat-shock protein (HSP)47 is a useful cell marker for skin fibroblasts in formalin-fixed, paraffin-embedded skin specimens. BACKGROUND: HSP47, a 47-kDa HSP, is a collagen-specific molecular chaperone localized in the endoplasmic reticulum. HSP47 plays an essential role in collagen biosynthesis in skin fibroblasts. METHODS: Immunohistochemistry was performed to detect HSP47 in skin fibroblast cultures and skin tissue sections. RESULTS: Immunostaining for HSP47 clearly detected skin fibroblasts in paraffin tissue sections as well as in fibroblast cultures and frozen tissue sections. HSP47 staining on paraffin sections from diseased skin specimens revealed that skin ulcer, keloid, nodular fascitis, spindle cell lipoma, and dermatofibroma had strong signals for HSP47 compared with the signals obtained from normal skin. Dermatofibrosarcoma protuberans had many HSP47 positive cells, but signals on individual cells were not as strong as those seen from the above benign proliferative disease samples. In neurofibroma, a small number of faintly positive cells were detected. Our double-immunostaining studies also demonstrated that HSP47 staining distinguished skin fibroblasts from CD68-positive histiocytes/macrophages, factor VIII-related antigen-positive endothelial cells, or factor XIIIa-positive dermal dendritic cells. CD34-positive interstitial cells coexpressed HSP47 in spindle cell lipoma. CONCLUSIONS: These findings indicate that HSP47 staining can detect skin fibroblasts in routine, paraffin-embedded specimens. A panel approach using HSP47 and other cell markers on paraffin sections may help the identification of the cell type involved with mesenchymal proliferative disorders.

Biomarkers↗

PubMed1991

A monoclonal antibody (OPT1) to T cells which is available for paraffin-embedded materials.

A monoclonal antibody (MAb), OPT1, reactive with T cells in formalin-fixed, paraffin-embedded tissue sections, has been identified through immunization with activated T cells from peripheral blood lymphocytes (PBL). The antibody is an IgG1 antibody as demonstrated by the Ouchterlony technique. By cytofluorometric analysis, almost all CD3+ lymphocytes and only a few CD20+ lymphocytes of peripheral blood expressed the OPT1 antigen. Nonhematolymphoid cell lines were negative for OPT1 by the immunoperoxidase staining using acetone-fixed cell lines. On the contrary, peripheral T cells, cells of two T cell lines out of four and a part of the cells of one B cell line out of two were positive for OPT1. The immunoperoxidase staining of paraffin-embedded tissue sections revealed that most of lymphocytes in T cell areas of lymph nodes expressed OPT1 antigen. Some lymphocytes in both cortex and medulla of the thymus and erythroid precursors of the bone marrow were OPT1+. In the malignant lymphoma series, approximately 90% of T cell lymphomas and 6% of B cell lymphomas reacted with OPT1. None of the Reed-Sternberg cells nor Hodgkin cells in Hodgkin's disease were positive. Consequently, OPT1 may be useful for the diagnosis and study of malignant lymphomas and other related lesions.

Antibodies, Monoclonal↗

PubMed1989

Methodological aspects of DNA image cytometry in formalin-fixed paraffin-embedded material from pancreatic adenocarcinoma.

Deparaffinized and disintegrated material from conventionally formalin-fixed and paraffin-embedded surgical specimens of 100 cases of ductal adenocarcinoma of the pancreas was Feulgen-stained, and the cytochemical DNA distribution patterns of at least 100 single tumour cells and 50 "control" cells (fibrocytes) were assessed by means of image cytometry (ICM). In 77 cases a sufficient number of neoplastic cells could be obtained for these DNA assessments. The fairly high number (23) of cases that had to be excluded due to too small amounts of disintegrated cells or cell nuclei may be explained by the high content of connective tissue stroma in these pancreatic adenocarcinomas. The tumour cell nuclei in 76 of these 77 cases showed cytochemically a clear-cut "non-diploid" DNA distribution pattern. This observation reflects the well-known highly malignant growth potential of this carcinoma. Despite the fact that about 1/4 of the tumours had to be excluded, the main result of our methodological study is, after all that conventionally formalin-fixed paraffin-embedded specimens of most pancreatic adenocarcinomas can be successfully used for the deparaffinization-disintegration procedure preceding the nuclear DNA assessments by means of ICM. Additional studies are, however, required to obtain the diagnostic and prognostic impact of the results of such cytochemical analyses of the DNA distribution pattern in adenocarcinomas of the pancreas.

Adenocarcinoma↗

PubMed1993

Comparison of pepsin and trypsin digestion on paraffin-embedded tissue preparation for DNA flow cytometry.

Preparation with enzymes plays an important part in obtaining good results in cellular DNA content measurements from paraffin-embedded tissue using flow cytometry. Therefore, we have compared two groups of DNA histograms obtained with pepsin (Hedley method) and trypsin digestion (Schutte method). Samples of five tumor types were compared: eight lung, seven breast, five thyroid, seven stomach, and six colon cancer cases. All samples were stained with propidium iodide (PI). The incidence of DNA aneuploidy determined by the Schutte method indicated a higher ratio in four tumor types than that determined by the Hedley method. Concerning the coefficient of variation (CV) used to estimate the quality of the DNA histogram, the diploid G1 peak determined by the Schutte method produced a smaller CV in five tumor types than did the Hedley method. This Schutte method had especially good results in lung and thyroid cancer. Furthermore, the amount of debris (background) determined by the Schutte method indicated a decrease in four tumor types compared with the Hedley method. In cell-cycle analysis of ten DNA diploid cases, DNA histograms by the Hedley method showed an increased S-phase fraction due to an overlapping of debris and aggregated cells. These results indicate that preparation by trypsin digestion is a method superior to pepsin digestion when the sample from paraffin-embedded tissue is stained with PI for the purpose of DNA content measurement.

Breast Neoplasms↗

PubMed1999

Molecular detection of EWS-FLI1 chimeric transcripts in Ewing family tumors by nested reverse transcription-polymerase chain reaction: application to archival paraffin-embedded tumor tissues.

Chromosomal translocations generating unique chimeric genes are highly characteristic of specific sarcomas, and their use as diagnostic markers has been suggested. From a diagnostic pathologic point of view, detection of such cytogenetic or molecular aberrations applicable to routinely processed archival tissue specimens is considered a powerful tool for tumor diagnosis. To assess the feasibility and reliability of the molecular detection of the transcript originating from the chimeric gene in paraffin-embedded tumor specimens, we performed a nested reverse transcription-polymerase chain reaction (RT-PCR)-based assay to detect the EWS-FLI1 chimeric message in a series of Ewing family tumors. Of 24 paraffin-embedded tumor specimens from 23 cases analyzed, the chimeric message was detectable in 20 (83%) specimens from 20 cases (87%) by this nested RT-PCR assay, whereas none of 7 small round cell tumors not from this family (3 alveolar rhabdomyosarcomas, 2 neuroblastomas, 2 malignant lymphomas) showed detectable chimeric messages. In the sequence analysis of the PCR products, the amplified chimeric messages contained the junctions between exon 7 of the EWS gene and any one of exons 5, 6 and 8 of the FLI1 gene. The detection process was usually completed within 3 days, except for the subseqent sequence analysis. Our results endorse the use of this molecular assay as an ancillary technique in the diagnosis of Ewing family tumors using paraffin-embedded material.

Adolescent↗

PubMed2000

Combined analysis of DNA ploidy, proliferation, and apoptosis in paraffin-embedded cell material by flow cytometry.

A flow cytometric assay was developed for correlated measurement of DNA content and apoptotic DNA strand breaks in cell nuclei of formalin-fixed, paraffin-embedded tissues. The assay allows a combined analysis of cell ploidy, proliferation, and apoptosis in sections of fixed paraffin-embedded archival or fresh tissue/cell specimens. It is based on (a) proteolytic release of cell nuclei from deparaffinized and rehydrated 90-microm thick sections of the fixed embedded specimen, (b) the inactivation of the protease, (c) FITC-labeling of DNA strand breaks by the terminal deoxynucleotidyl transferase (TdT)-mediated FITC-dUTP nick end-labeling (TUNEL) reaction, and (d) DNA staining with 4'6-diamidino-2-phenyleindole. The fluorescence was recorded with a double-beam flow cytometer equipped with a mercury arc lamp and an argon ion laser. Cytograms obtained with this assay correlated closely with those produced using nonembedded material from the same specimen. Furthermore, a significant correlation was found between flow cytometric analysis of apoptosis in cell nuclei released from paraffin blocks and conventional evaluation of TUNEL on (corresponding) sections (p < 0.001). Since necrotic cells can stain positively by TUNEL, the possibility to microscopically select nonnecrotic tumor regions for flow cytometric analysis is an important advantage of the assay.

Apoptosis↗

PubMed1995

PCR analysis of hepatitis B virus DNA in paraffin-embedded liver tissue from patients with chronic liver disease.

We described a nested polymerase chain reaction protocol to detect hepatitis B viral DNA in paraffin-embedded liver tissue and tried to determine whether this virus was associated with non-B chronic liver disease. Fifty-five samples were obtained from 28 patients with B, and 27 patients with non-B chronic liver disease (35 cirrhosis, 4 hepatocellular carcinoma and 16 chronic hepatitis). The two sets of primers amplify a sequence located in a conserved polymerase/surface region of the viral genome. Reaction products were analysed using a nonisotopic hybridization method. None of the 27 (0%) seronegative samples and 20 of the 28 (71%) seropositive specimens were positive for hepatitis B virus DNA. There were 4 false negatives in which beta-globin PCR was positive. Although its sensitivity is reduced in formalin-fixed paraffin-embedded tissue, nested PCR allows rapid detection of HBV DNA sequences and can be a useful tool if no frozen tissue is available.

Adolescent↗

PubMed1996

Identification of monoclonal antibodies for immunohistochemical staining of feline B lymphocytes in frozen and formalin-fixed paraffin-embedded tissues.

Commercially-available monoclonal antibodies to B lymphocytes were evaluated for immunohistochemical staining of feline B lymphocytes in frozen and formalin-fixed, paraffin-embedded tissues using an avidin biotin complex immunoperoxidase immunohistochemical technique. Three monoclonal antibodies: F46A and F72A raised to "carnivore" B lymphocytes and RA3.6B2 raised to murine B lymphocytes, stained B lymphocyte-dependent areas of frozen feline lymphoid tissue. In addition, antibody RA3.6B2 stained B lymphocyte dependent areas in formalin-fixed, paraffin-embedded feline tissues. There was no staining of T lymphocyte-dependent areas in either frozen or formalin-fixed tissues. Dual parameter flow cytometry, using an anti-pan-T lymphocyte antibody, revealed that greater than 99% of the cells stained by RA3.6B2 are a population distinct from T lymphocytes. F46A was shown to stain a sub-population of those cells stained with RA3.6B2. These antibodies may be useful in the identification of feline B lymphocytes using immunohistochemistry and flow cytometry and thereby provide additional tools to study B lymphocyte ontogeny and the significance of lymphocyte phenotype in lymphoid neoplasia in cats.

Animals↗

PubMed2002

Value of PCR technique in detection of Helicobacter pylori in paraffin-embedded material.

Methods which permit effective detection of Helicobacter prlori are based on endoscopic sampling of gastric mucosa followed by a direct or indirect demonstration of Helicobacter pylori bacilli, e.g. searching for specific proteins or gene fragments. PCR technique represents one of techniques employed for diagnosing the biopsies. The present study was aimed at examining how effective is the detection of Helicobacter pylori in paraffin-embedded material by PCR technique using primers for the Ure C gene fragment. The material for studies involved gastric biopsies, routinely fixed in formalin and embedded in paraffin. In order to perform PCR, DNA was isolated and purified, subjected to amplification with the use of starters for the Ure C gene fragment. The performed experiments have confirmed suitability of PCR technique for detection of Helicobacter pylori.

DNA, Bacterial↗

PubMed1997

Detection of serum amyloid A-derived proteins in formalin-fixed paraffin-embedded tissues: reliability of the method and expansion of its spectrum.

To further assess the reliability of the Shtrasburg method for detection of amyloid A in formalin-fixed, paraffin-embedded tissues and to expand the spectrum of the amyloid proteins analyzed by this method, we studied formalin-fixed, paraffin-embedded amyloid-containing tissues obtained from patients with the following types of amyloidosis: amyloid A, light chain, transthyretin, calcitonin, beta2 microglobulin, and senile seminal vesicle. The tissue samples were deparaffinized, processed, and subjected to sodium dodecyl sulfate-polyacrylamide gel electrophoresis and the Western blot technique. Only specimens from patients with amyloid A amyloidosis gave protein bands: a single 8.5-kd band in lanes of all tissues studied, except thyroid tissue, which displayed two bands of about 5 and 10 kd. Other types of amyloid failed to show any protein band. These findings suggest that the Shtrasburg method is sensitive, specific, and reliable and may have an important role in the diagnosis of amyloidosis.

Amyloidosis↗

PubMed1995

Immunostaining of chain-specific keratins on formalin-fixed, paraffin-embedded tissues: a comparison of various antigen retrieval systems using microwave heating and proteolytic pre-treatments.

The use of chain-specific monoclonal antibodies (MAbs) against keratins in pathology is hampered by their limited staining on formalin-fixed, paraffin-embedded tissue. In the present study, various treatments before immunohistochemistry on paraffin sections were compared, including proteolytic enzymes and microwave antigen retrieval in various solutions. Sections of normal cervical and skin tissue were stained in a three-step immunoperoxidase method, employing a broad panel of MAbs against chain-specific keratins 4, 5, 7, 8, 10, 13, 14, 17, 18, 19 and pankeratin. Using microwave heating, Target Unmasking Fluid (TUF), Antigen Retrieval Solution (ARS), a simple detergent solution (DET), PBS, and distilled water (MiQ) were compared. Microwave heating in PBS or MiQ strongly improved staining results. Moreover, microwave pre-treatment in TUF or DET gave excellent and specific staining with the majority of MAbs tested, comparable with or even better than staining obtained on frozen sections. Using microwave antigen retrieval, tissue morphology remained optimal, and only in a very limited number of MAbs did immunoreactivity on paraffin sections fail to be restored. Proteolytic pre-treatment with trypsin, pepsin, or pronase gave moderate to strong staining with some of the MAbs. Other MAbs, for which microwave pre-treatment was able to restore the loss of immunoreactivity, failed to give appropriate staining with proteolytic pre-treatment. Our results show that microwave heating in either TUF or a simple detergent solution before immunohistochemistry is a reliable method for antigen retrieval of chain-specific keratins in formalin-fixed, paraffin-embedded tissues.

Antibodies, Monoclonal↗

PubMed1987

The formaldehyde-fixed and paraffin-embedded tissues for diagnostic transmission electron microscopy: a retrospective and prospective study.

The fine structures of tissues processed routinely for light microscopy were studied retrospectively in 44 tissues and tumors and prospectively in 13 tissues and tumors. In the prospective study, we fixed tissues in an ample amount of fixatives, carefully avoiding crushed and air-dried portions, and processed them by five methods. The fine structures of the retrospective cases were mostly poor or passable, whereas those of the prospective cases were generally good. All formaldehyde-fixed tissues showed varied degrees of tissue extraction, notably of lipids, membranous structures, ribosomes, glycogen, and other loose cellular and intercellular matrix materials, that was related to the status and type of tissue as well as the kind and duration of fixation, dehydration, and tissue clearance. Paraffin embedding per se appeared to cause little alteration of the fine structure. Transmission electron microscopy of the paraffin-embedded tissue appeared most useful to identify infective agents, foreign particles, and densely packed organelles or structures, usually in the differential diagnosis of neoplasms. Although many factors are difficult to control, initial careful thin slicing, judicious selection, and fixation of the tissue (even by regular phosphate-buffered formaldehyde solution) can improve the fine structure of paraffin-embedded tissues and be useful in the direct correlation of light and electron microscopic findings.

Bone Marrow Diseases↗

PubMed1995

Detection of clonal lambda light chain gene rearrangements in frozen and paraffin-embedded tissues by polymerase chain reaction.

A method was established to detect clonal lambda light chain gene rearrangements in peripheral blood lymphocytes and frozen or paraffin-embedded tissues. V lambda-gene-family-specific primers were used together with a J lambda primer mix in separate reactions to amplify V lambda gene rearrangements by the polymerase chain reaction. Clonal lambda gene rearrangements were detected in seven of seven lambda-expressing B cell leukemias, in four of five lambda-expressing non-Hodgkin's lymphomas with frozen tissues, and in seven of nine cases of lambda-expressing non-Hodgkin's lymphomas for which formalin-fixed, paraffin-embedded specimens were available. Clonality of amplified polymerase chain reaction products was confirmed by sequence analysis for several cases. The present study shows that it is possible to amplify clonal lambda gene rearrangements in the majority of lambda-expressing B cell leukemias and lymphomas. The method described here, therefore, is a useful supplement to the previously described approach of VH and VK gene amplification to detect clonal B cell populations and allows the study of V lambda gene usage and somatic mutation in lambda-expressing normal and malignant B cells.

Amino Acid Sequence↗

PubMed1993

[Adverse effect of prolonged formalin fixation on DNA ploidy in paraffin-embedded tissue].

From retrospective analysis of 174 formalin fixed, paraffin-embedded, HCC tissue samples, the possible correlation was investigated between the CV determined by FCM and the duration of formalin fixation. An adverse effect of prolonged formalin fixation on CV and fluorescence intensity in liver tissue was investigated prospectively in samples from 4 patients.

DNA, Neoplasm↗

PubMed1989

Improved histology from inadequately fixed paraffin-embedded biopsy specimens.

The rapid turnaround time demanded of many surgical pathology laboratories often results in the paraffin embedding of biopsy specimens that are less than optimally fixed. Occasionally, the quality of the resulting hematoxylin-and-eosin-stained sections is inadequate to provide a diagnosis. A method is described herein that permits the preparation of histologic sections of excellent quality from suboptimally fixed paraffin-embedded tissue.

Histological Techniques↗