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Reactivity of anti-AraC-resistant cell monoclonal antibody, YU-311, in formalin-fixed paraffin-embedded specimens of various hematopoietic disorders.

YU-311 is a monoclonal antibody reacting with cytosine arabinoside (AraC)-resistant human leukemic cell line and identifies a 92 kDa membrane protein. We have examined YU-311 reactivity with various hematopoietic disorders by an immunohistochemical method and evaluated a correlation between YU-311 expression and refractoriness to chemotherapy, retrospectively. YU-311 reacted with AraC-resistant human leukemia cell lines, in which a 92 kDa membrane protein was identified by Western blotting, whereas drug-resistant cell lines to other than AraC failed to express YU-311 antigen. The frequency of YU-311 positivity was significantly increased in relapsed cases. Only five cases were positive for YU-311 at diagnosis and 24 cases at relapse. Unexpectedly, only eight cases of relapsed leukemia/lymphoma expressed YU-311 and P-glycoprotein simultaneously. Most of the YU-311-positive relapsed cases showed clinical refractoriness for chemotherapy and then failed to induct complete remission or relapsed at short periods with short disease-free duration. These findings indicate that YU-311 expression is closely associated with some aspects of drug resistance, especially with AraC resistance.

ATP Binding Cassette Transporter, Subfamily B, Mem↗

Use of monoclonal antibodies (UCHL1, Ki-B3) against T and B cell antigens in routine paraffin-embedded skin biopsy specimens.

Diagnosis and classification of cutaneous lymphoid infiltrates are often hampered by lack of frozen tissue to allow detailed immunophenotyping. Therefore antibodies that recognize antigens resistant to routine tissue processing would be of value. In this study we present a detailed analysis of two such antibodies against CD45R antigens, UCHL1 and Ki-B3, that detect predominantly T or B cells, respectively. Tumor cells in 125 cases of various nonlymphatic skin tumors did not react with either UCHL1 or Ki-B3. Examination of 85 biopsy specimens from 13 different inflammatory skin diseases demonstrates that most reactive T cells in the skin carry the UCHL1 antigen, as controlled by simultaneous immunophenotyping in frozen tissue. With few exceptions, UCHL1 also detected the tumor cells in 28 cases of cutaneous malignant T cell lymphomas. In contrast, Ki-B3 failed to detect tumor cells in seven of eight cases of malignant B cell lymphomas of the skin.

Antibodies, Monoclonal↗

Gastrointestinal beta2microglobulin amyloidosis in hemodialysis patients: biochemical analysis of amyloid proteins in small formalin-fixed paraffin-embedded tissue specimens.

We present here a first report on the biochemical analysis of intestinal amyloid deposits found in two cases of hemodialysis-related amyloidosis. A new microtechnique was applied for extraction and immunochemical/chemical characterization of amyloid proteins in small amounts of fixed tissue, thus allowing precise identification of beta2microglobulin amyloid (Abeta2M) in both cases studied. The molecular mass of the identified amyloid beta2M was close to that of intact beta2M (12 kDa), with no evidence of the products of proteolytic fragmentation of these molecules. The isoelectrofocusing of the purified Abeta2M demonstrated a shift to more acidic pI as compared to the normal beta2M analyzed under the same experimental conditions. The obtained data suggest that the intestinal amyloid deposits in dialysis-related amyloidosis contain disease-specific beta2M isoforms, which could play a role in the pathogenesis of amyloid disease. The new methodology used might be useful in obtaining precise diagnosis of amyloidosis that is necessary for appropriate therapy, and also provide new important information on the chemical structure of amyloid proteins.

Aged↗

A novel immunohistochemical method for estimating cell cycle phase distribution in ovarian serous neoplasms: implications for the histopathological assessment of paraffin-embedded specimens.

We have investigated whether immunohistochemical markers can identify differences in cell cycle phase distribution in ovarian serous neoplasms, including borderline tumours of different grades. Sections of normal ovary (n=18), serous cystadenoma (n=21), borderline serous tumours (n=21) and serous cystadenocarcinoma (n=15) were analysed by immunohistochemistry using markers of cell cycle entry (Mcm-2) and cell cycle phase, including cyclin D1 (mid-to-late G1), cyclin A (S phase), cyclin B1 (G2 phase) and phosphohistone H3 (mitosis). Double-labelling confocal microscopy confirmed marker phase specificity and phase estimations were corroborated by flow cytometry. On progression from normal ovary through serous cystadenoma and borderline tumours to cystadenocarcinomas, expression of Mcm-2 (P<0.0001), cyclin D1 (P=0.002), cyclin A (P<0.0001), cyclin B1 (P<0.0001) and phosphohistone H3 (P<0.0001) increased, paralleled by an increase in the S-phase fraction (cyclin A : Mcm-2 ratio; P=0.002). Borderline tumours of increasing grade also showed increased Mcm-2 and cyclin A expression, together with an increase in the S-phase fraction. Immunohistochemistry can be used to estimate cell cycle phase distribution in ovarian serous neoplasms, giving results similar to flow cytometric analysis and enabling direct assessment of tumour heterogeneity. Immunohistochemical estimates of the S-phase fraction may identify serous borderline tumours likely to exhibit malignant progression and/or select serous cystadenocarcinomas likely to respond to adjuvant therapy.

Biomarkers, Tumor↗

Diagnostic and prognostic value of the MB2 monoclonal antibody in paraffin-embedded bone marrow sections of patients with multiple myeloma and monoclonal gammopathy of undetermined significance.

Routinely processed bone marrow biopsies of 59 patients with untreated multiple myeloma (MM) and of 41 patients with monoclonal gammopathies of undetermined significance (MGUS) were immunocytochemically studied with the MB2 monoclonal antibody. In 54 of 59 biopsies of patients with MM, most neoplastic plasma cells showed strong cytoplasmic positivity to MB2. In contrast, only three biopsies of patients with MGUS contained highly MB2-positive plasma cells, whereas the plasma cells in the remaining biopsies were either negative (18 of 41) or revealed a weak dot-like staining of the cytoplasm (20 of 41). Plasma cells in tonsillar tissue, gastric and duodenal mucosae, and bone marrow with reactive plasmacytosis were not stained with MB2. These findings suggest that MB2 helps to distinguish between MM and MGUS. Because the five MB2-negative patients with MM were all in stage III and had very short survival time, neoplastic plasma cell staining with MB2 could also have a prognostic significance.

Antibodies, Monoclonal↗

Immunohistochemical identification of aggregated actin filaments in formalin-fixed, paraffin-embedded sections. I. A study of infantile digital fibromatosis by a new pretreatment.

Some authors have claimed that actin is not immunostained in characteristic intracytoplasmic inclusions of infantile digital fibromatosis, whereas others have claimed that it is. Formalin-fixed specimens were used in the former studies; specimens fixed in alcohol used in the latter studies. Actin at other sites, such as the rim of the inclusions, was distinctly immunostained even in the formalin-fixed specimens. Such phenomena make it difficult to accept the loss of antigenicity of actin as a result of formalin fixation. The use of usual pretreatment with trypsin provided the same results. We were able to immunostain actin distinctly and strongly in the inclusions for the first time in formalin-fixed specimens by combining KOH in 70% ethanol and trypsin. This successful staining results from the adequate etching effect of trypsin, which occurs because of a loosening of proteins in the inclusions due to KOH. These phenomena suggest that steric hindrance of antigen determinant has occurred only in the inclusions as a result of intramolecular cross-linkage, because of extremely dense accumulation of actin filaments in the inclusions.

Actin Cytoskeleton↗

Quantitation of dihydropyrimidine dehydrogenase (DPD) mRNA expression levels in normal colon and colorectal cancer tumor paraffin-embedded tissue specimens.

5-Fluorouracil (5-FU) has been used for more than 40 years in the treatment of neoplastic disease, and remains the standard first-line treatment for colorectal cancer in combination with irinotecan and leucovorin. Previous studies indicated that measurement of dihydropyrimidine dehydrogenase (DPD) gene expression before treatment was valuable in determining the potential benefit of and toxicity to 5-FU treatment. In this study, we investigated the association between intratumoral DPD gene expression and the adjacent normal tissue DPD gene expression and DPD mRNA expression level in non-paired colon tumor and normal colon tissue specimens. In addition, we have compared the difference of DPD gene expression at three different RNA concentrations from the same specimen (180, 100 and 5 ng/reaction, respectively). DPD expression was measured by quantitative RT-PCR using a LightCycler instrument in a total of 31 specimens. Gene expression values were expressed as a ratio of target gene (DPD) to the internal reference gene (G6PDH). Our study revealed no statistically significant difference (p=0.23) between tumor tissues and matched normal tissue in DPD expression. In contrast, the data on DPD mRNA expression in non-paired colon tumor and normal tissue specimens revealed a significant difference (p=0.0004) between the tumor group and the normal group. In the three RNA concentration groups, there was no significant difference (p=0.55) in gene expression at the different RNA concentrations from the same donor. These results demonstrate that intratumoral gene expression levels of DPD do not correlate with tumor cell percentage or with RNA concentration. Thus, DPD mRNA expression appears to be a valid sensitivity test for 5-FU in spite of a varying density of tumor cells and RNA yield in specimens submitted for analysis.

Antineoplastic Agents↗

The immunohistochemical application of three anti-GFAP monoclonal antibodies to formalin-fixed, paraffin-embedded, normal and neoplastic brain tissues.

The intermediate filament, glial fibrillary acidic protein (GFAP) has proven to be an important glial marker in diagnostic neuropathology. We report the histochemical application of three monoclonal antibodies (Mab) produced in this laboratory, 1B4, 2E1, and 4A11, which are monospecific to GFAP by radioimmunoassay, immunoblot electrophoresis, and immunoperoxidase histochemistry. The goal of this study was to compare the specificity and sensitivity of these Mab to GFAP on surgical brain biopsy specimens which had been routinely processed for diagnostic neuropathology with that of a high titer, highly specific, reference polyvalent anti-GFAP antiserum. The Mab stained astrocytes specifically in normal brain. When combined in a "cocktail" preparation, the quality of the immunoperoxidase detection of GFAP by these Mab closely approached that of the reference serum in 71 intracranial and intraspinal neoplasms. As these three Mab represent a continuous supply of a well defined, monospecific reagent, the monoclonal "cocktail" represents a standard reagent for large multi-institutional studies and for studies extending over a period of time.

Antibodies, Monoclonal↗

Protein kinase C (PKC) isoenzymes immunohistochemistry in lymph node revealing solution-fixed, paraffin-embedded bladder tumors.

Protein kinase C (PKC) plays an important role in cellular differentiation and in the malignant process. In an earlier study, it was shown that the expression pattern of PKC isoenzymes is altered in some tumors compared to their corresponding normal tissue. In this study, we evaluated the pattern of PKC isoenzyme immunostaining in bladder transitional cell carcinoma (TCC) of different grades and stages and normal tissue. Twenty-seven TCC samples and six areas of normal bladder mucosa were stained with antibodies specific for the PKC isoenzymes: alpha, beta 1, beta 2, delta, and zeta. The sections were scored for intensity of staining, and the correlation with grade and stage of the tumors was computed. The PKC alpha and beta 2 immunostains were intense in normal urothelium and in all evaluated tumors. PKC beta 1 and delta stains were intense in normal and low-grade and -stage tumors and weak in high-grade and -stage tumors. The opposite trend was found for PKC zeta. PKC isoenzyme expression differs in invasive TCC compared to low-grade, low-stage TCC and normal urothelium. The value of these findings as a marker of tumor aggressiveness should be further assessed.

Aged↗

PCR-based diagnosis of enterovirus and parvovirus B19 in paraffin-embedded heart tissue of children with suspected sudden infant death syndrome.

The diagnosis of viral myocarditis remains difficult and generally depends on clinical and histologic criteria. Viral cultures and serology are often unrewarding with low yields. The purpose of this study was to analyze the usefulness of PCR in the rapid diagnosis of myocarditis in children. PCR was used to analyze 120 myocardial tissue samples from 60 cases of sudden infant death syndrome (SIDS) and 56 myocardial tissue samples from 36 cases with well-known causes of sudden death (11 children younger than 1 year and 25 children 1-10 years old). The myocardial tissue samples were evaluated for the presence of enteroviruses and parvovirus B19 using PCR primers designed to consensus and unique sequences of these viral genomes. Enteroviruses could be detected in 14 cases of SIDS, whereas the detection of enteroviral nucleic acid within the control group was negative. Seven cases with myocardial infection caused by parvovirus B19 were found in the SIDS group. The detection of parvoviruses in the control group of the 11 children younger than 1 year was negative, whereas 3 positive cases of parvoviruses could be detected in the control group of children from 1 to 10 years old. In the myocardial sample of one SIDS case, both enteroviruses and parvovirus B19 could be detected. Our results emphasize the importance of modern molecular biologic methods in cases of sudden infant death even when conventional histologic examination revealed no serious findings in heart muscle tissue.

Adolescent↗

The role of immunoperoxidase techniques on paraffin embedded tissue in determining the histogenesis of undifferentiated thyroid neoplasms.

Twenty cases of undifferentiated thyroid tumours were reviewed histologically. In seven cases the histogenesis was difficult to determine using morphological criteria. Immunohistochemical staining with a panel of antibodies to lymphoid and epithelial cells, including monoclonal antibodies directed against the leucocyte common antigen, cytokeratin, and epithelial membrane antigen confirmed that four of these cases were lymphomas and that one was a medullary carcinoma. In the remaining two cases immunohistochemistry was unhelpful. In the thirteen histologically typical tumours, the immunohistochemical profile was in keeping with their histogenesis as determined by morphological criteria. Immunohistochemical staining with a panel of selected antibodies allows the reliable diagnosis of undifferentiated thyroid neoplasms, when this cannot be reached using routine histological techniques.

Aged↗