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Steven D Billings Shaun V Walsh Cyril Fisher Asma Nusrat Sharon W Weiss Andrew L Folpe 《Modern pathology》2004,17(2):141-149
Synovial sarcoma demonstrates epithelial differentiation, either by light microscopy (biphasic synovial sarcoma) or by immunohistochemical/ultrastructural methods only (monophasic) and poorly differentiated synovial sarcoma. Although the glands of synovial sarcoma are known to have tight junction-like structures, far less is known about junction formation in the spindled component of synovial sarcomas. Additionally, it is unknown whether the tight junctions of synovial sarcoma are normally constituted. The tight junction is a multiprotein complex consisting of numerous proteins that include ZO-1, claudin-1 and occludin. A total of 35 cases of synovial sarcoma (13 biphasic, 14 monophasic and eight poorly differentiated) were immunostained for ZO-1, claudin-1 and occludin using commercially available antibodies, heat-induced epitope retrieval and standard avidin-biotin technique. When available, corresponding electron micrographs were reviewed. For five cases, the presence of either an SYT-SSX1 (three cases) or SYT-SSX2 (two cases) gene fusion was known. Positive cases showed particulate membrane staining. The glands of biphasic synovial sarcomas expressed ZO-1 (13/13), claudin-1 (12/13) and occludin (11/13) in a manner identical to normal glandular epithelia, at the apical portion of the lateral membrane. The spindle cells of biphasic synovial sarcomas showed abnormal circumferential membranous expression of ZO-1 (12/13), claudin-1 (6/13) and occludin (3/13). Monophasic synovial sarcomas expressed ZO-1 in a circumferential pattern (13/14) but less often claudin-1 (4/14) or occludin (3/14). Poorly differentiated synovial sarcomas expressed ZO-1 (8/8) and claudin-1 (6/8) but only rarely occludin (2/8). By electron microscopy, recognizable tight junctions were seen only in glands. No correlation was seen between histologic subtype or fusion type and expression of tight junction proteins. We conclude that the glands of biphasic synovial sarcomas show well-organized, true epithelial tight junctions. In contrast, the spindled cells of all synovial sarcomas show significant abnormalities in the expression and localization of tight junction proteins, suggesting partial and/or aberrant epithelial differentiation. 相似文献
7.
Studies of proteins that inhibit tissue factor activity have generally been conducted using either an extracted tissue homogenate ("thromboplastin") or tissue factor protein reconstituted into phospholipid vesicles rather than with tissue factor expressed in cell membranes (its physiological environment). In the present study, a human fibroblast cell strain was used to evaluate the effects of lipoprotein associated coagulation inhibitor (LACI), placental anticoagulant protein (PAP), and apolipoprotein A-II (apo A-II) on human tissue factor in cell membranes. LACI was tested from 7.8 to 500 pmol/L on fibroblasts cultured at cell densities ranging from 3,500 to 9,925 cells/well, and caused a progressive inhibition of tissue factor activity. PAP was tested from 3.9 nmol/L to 1 mumol/L at cell densities ranging from 4,500 to 15,400 cells/well and caused up to 83% inhibition of tissue factor activity. Inhibition by these proteins appeared to be influenced by cell density as well as whether the cells were intact or disrupted. Apo A-II, up to 1 mumol/L, did not inhibit the tissue factor activity of intact or disrupted fibroblasts at any cell density examined even though it did inhibit the activity of tissue factor in phospholipid vesicles. Of these inhibitors of tissue factor-dependent activation of factor X, LACI was the most effective in suppressing the generation of factor Xa activity. The effects obtained with apo A-II are clearly dependent on the nature of the tissue factor preparation with which it is tested. The disparity between the inhibitory effect of apo A-II on the activity of tissue factor reconstituted into lipid vesicles and the absence of effect on the activity of tissue factor remaining in cell membranes serves to reemphasize the necessity of reexamining results obtained with model systems using as nearly physiological reagents as possible. 相似文献
8.
Identical allelic losses in mature teratoma and other histologic components of malignant mixed germ cell tumors of the testis 总被引:3,自引:0,他引:3
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Kernek KM Ulbright TM Zhang S Billings SD Cummings OW Henley JD Michael H Brunelli M Martignoni G Foster RS Eble JN Cheng L 《The American journal of pathology》2003,163(6):2477-2484
Teratomas of the testis in post-pubertal patients are histologically diverse tumors that often coexist with other types of germ cell tumors. Using laser capture microdissection and loss of heterozygosity analysis, we investigated the clonality of mature teratoma and its relationship to other components of malignant mixed germ cell tumors to gain potential insight into the histogenetic relationship of teratoma with other germ cell tumor components. All 16 patients had mature teratoma as one component of their mixed germ cell tumors. The other histological subtypes included immature teratoma, seminoma, embryonal carcinoma, yolk sac tumor, and choriocarcinoma. Laser-assisted microdissection was performed on the formalin-fixed, paraffin-embedded tissue. Polymerase chain reaction was used to amplify genomic DNA at specific loci on chromosome 1p36.2 (D1S508), 2q22-32 (D2S156), 9p21-22 (D9S162), 11p13 (D11S903), 12q22-23 (D12S1051), and 18q21 (D18S46). Fourteen of 16 (88%) cases showed allelic loss in one or more components of the mixed germ cell tumors. Fourteen of 16 mature teratomas showed allelic loss in at least one of six microsatellite polymorphic markers analyzed. The frequency of allelic loss in mature teratoma was 50% (7 of 14) with D1S508, 33% (5 of 15) with D2S156, 58% (7 of 12) with D9S162, 43% (6 of 14) with D11S903, 20% (3 of 15) with D12S1051, and 33% (5 of 15) with D18S46. Completely concordant allelic loss patterns between mature teratoma and all of the other germ cell tumor components were seen in 10 of 14 tumors in which mature teratoma showed loss of heterozygosity. Our data support the common clonal origin of mature teratoma with other components of malignant mixed germ cell tumors of the testis. 相似文献
9.
Hormonally functional ovarian neoplasms are those tumors that secrete one or more hormones that are clinically manifested
in the patient. The hormone production may have implications for the diagnosis, management, or treatment of the patient. Hormonally
functional ovarian neoplasms include tumors that belong to various histologic categories and produce a variety of hormonal
effects. Functional ovarian tumors most commonly produce steroid hormones, and such tumors frequently belong in the sec cordstromal
and steroid cell categories. In addition, a wide variety of peptide hormones may be produced by ovarian tumors. Although in
most instances the neoplastic cells themselves produce the hormones, a wide variety of tumors may induce their stroma to produce
steroid hormones. The stroma of ovarian tumors is derived from the ovarian stroma and may, on occasion, resemble specialized
ovarian stroma and its derivatives. Cells resembling luteinized stromal cells or luteinized theca cells may be present and
appear to be responsible for the resultant hormone secretion. 相似文献
10.
Myosin VIIA gene: heterogeneity of the mutations responsible for Usher syndrome type IB 总被引:8,自引:1,他引:8
Levy G; Levi-Acobas F; Blanchard S; Gerber S; Larget-Piet D; Chenal V; Liu XZ; Newton V; Steel KP; Brown SD; Munnich A; Kaplan J; Petit C; Weil D 《Human molecular genetics》1997,6(1):111-116
Usher syndrome is recognized as the most frequent cause of hereditary
deaf-blindness. Usher syndrome type I (USH1), the most severe form of the
disease, is characterized by profound congenital sensorineural deafness,
constant vestibular dysfunction, and retinitis pigmentosa of prepubertal
onset. This form is genetically heterogeneous and five loci (USH1A-E) have
been mapped thusfar. However, only the gene responsible for USH1 B (which
accounts for approximately 75% of USH1 cases) has been characterized. It
encodes a long-tailed unconventional myosin, myosin VIIA, with a predicted
2215 amino acid sequence. Primers covering the complete myosin VIIA coding
sequence as well as the 3' non coding sequence were designed, allowing
direct sequence analysis of each of the 48 coding exons and flanking splice
sites in seven patients affected by USH1. Four novel mutations were thereby
identified. The possibility should now be considered of a sequence-based
prenatal diagnosis in some of the families affected by this very severe
form of Usher syndrome.
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