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Biomedical subjects

J A Bridge

Publications and source records attributed to J A Bridge.

At least 73 records · Page 4Linked to original sources
PubMed1996

Chromosomal anomalies exclusive of telomeric associations in giant cell tumor of bone.

The occurrence of telomeric associations in giant cell tumor of bone is well recognized. However, there has been little emphasis on clonal structural abnormalities that may be seen in addition to or in the absence of telomeric associations. Two cases of giant cell tumor of bone are presented in this study demonstrating clonal karyotypic anomalies other than telomeric association with a review of previously reported cases showing similar findings.

Adult↗
PubMed1996

Cytogenetics and experimental models.

Cytogenetic analysis plays a direct, potentially decisive role in the examination of benign and malignant bond and soft tissue tumors. Translocations, or the exchange of chromosomal material between two or more nonhomologous chromosomes, are frequently encountered as tumor-specific anomalies in mesenchymal neoplasms. The consequences of many of these translocations has been the formation of chimeric proteins with features characteristic of altered transcription factors. Recent studies have revealed new tumor-specific translocations (eg, cemento-ossifying fibroma and myxoid chondrosarcoma) and the association of established translocations, eg, t(11;22) and t(12;16), in rare histologic subtypes such as biphenotypic sarcomas with myogenic and with neural differentiation and round cell liposarcoma, respectively. In contrast to a single translocation, many mesenchymal neoplasms such as malignant fibrous histiocytoma and osteosarcoma are characterized by multiple, often complex, chromosomal abnormalities. Recent advances in molecular cytogenetics, eg, in situ hybridization and comparative genomic hybridization, have made the identification of many of these abnormalities possible and in some instances, have revealed chromosomal imbalances not detectable with traditional cytogenetic analysis.

Chromosome Aberrations↗
PubMed1996

FMR1 fully expanded mutation with minimal methylation in a high functioning fragile X male.

Cytogenetic and molecular genetic analysis of a peripheral blood sample from a 31 year old, non-mentally retarded male with a family history of fragile X syndrome showed unexpected results. Nine percent of cells evaluated cytogenetically expressed a fragile X chromosome and molecular examination of the FMR1 gene showed a highly unusual pattern defined as a minimally methylated fully expanded mutation. This case illustrates the need to recognise exceptional variations of fragile X syndrome mutations.

Adult↗
PubMed1995

Translocation t(3;12)(q28;q14) in parosteal lipoma.

Parosteal lipoma is a rare primary benign bone tumor demonstrating histopathologic features similar to those seen in the commonly occurring lipoma of soft tissue. Cytogenetic studies of soft tissue lipoma have demonstrated frequent abnormalities of 12q13-15. To the best of our knowledge the cytogenetic findings in parosteal lipoma have not yet been described. Cytogenetic analysis of a parosteal lipoma of the femur of a 51-year-old female revealed a t(3;12)(q28;q14), indicating that bone and soft tissue lipomas are cytogenetically similar and likely share a common histopathogenesis.

Chromosome Mapping↗
PubMed1995

Expression of 72 kDa and 92 kDa type IV collagenases from human giant-cell tumor of bone.

Basement membrane forms widespread barriers to tumor invasion. It has been shown that tumor-secreted, basement membrane-degrading enzymes, namely metalloproteinases (MMPs) play an important role in tumor invasion and metastasis. In this study, we determined the enzymatic activity, content, and mRNA of both the 72 kDa (MMP-2) and 92 kDa (MMP-9) MMPs in primary cultures of human giant-cell tumor of bone (GCT) in vitro and in tissue extracts (in vivo). Gelatin zymography showed the presence of lytic bands at M(r) 121,000, 92,000, and 72,000, and these enzymatic activities were inhibited by EDTA, an inhibitor of MMPs. Western blots with antibodies specific for MMP-2 and MMP-9 confirmed the presence of MMP-2 and MMP-9 both in vitro and in vivo, but GCT cells at late passage showed only MMP-2. Northern blots using labeled cDNA probes specific for these molecules revealed the presence of 3.1 kb transcript for MMP-2 and a 2.9 kb transcript for MMP-9. Using specific antibodies to 72 kDa and 92 kDa type IV collagenases, we studied their cellular distribution by immunohistochemical means. Stronger immunoreactivity was found for 92 kDa type IV collagenase than 72 kDa type IV collagenase in the giant cells. It appears, therefore, that MMP-9 may play an important role in the malignant behavior of GCTs and suggests a potential therapeutic role for protease inhibitors in attempting to minimize the invasive behavior of GCTs.

Bone Neoplasms↗
PubMed1995

Cytogenetics and experimental models of sarcomas.

Bone and soft tissue sarcomas are diagnostically challenging. Recognition of specific cytogenetic abnormalities in these neoplasms has significantly reduced some of the associated difficulties and has provided valuable information on histopathogenesis. Commonly, translocations involving an exchange of chromosomal material and creation of novel chimeric genes are detected. These fusion genes frequently function as aberrant transcription factors that contribute to sarcomagenesis. New studies indicate that less commonly occurring variant fusion genes are also present in some tumors, eg, Ewing's sarcoma and alveolar rhabdomyosarcoma. The clinical consequences, if any, of these variant hybrids are not yet known. Reverse transcriptase polymerase chain reaction and are useful approaches in detecting these transcripts. In addition to translocations, supernumerary ring chromosomes are often encountered in sarcomas, particularly those of intermediate or borderline malignancy. Traditional fluorescence in situ hybridization, and recently, comparative genomic hybridization have uncovered the chromosomal composition of these rings as well as some associated gene amplifications in well-differentiated liposarcoma and dermatofibrosarcoma protuberans.

Animals↗
PubMed1994

Cytogenetic and molecular cytogenetic analysis of sacral chordoma.

A specific or characteristic anomaly has not yet been identified in chordoma. Cytogenetic analysis of a sacral chordoma from a 70-year-old male revealed the following chromosomal complement: 42,XY,add(1)(p11), -3,der(4)t(4;?;?18;?)(q12;?;?;), -6, -9, -14,der(16) t(4;?;16)(q12;?;q11), der(17)add(17)(p12) t(17;18)(q11;p11),der(18)del(18)(p11)add(18)(q?)[6]/42, idem,der(9)t(6;9)(q11;p11)[4]/46,XY[10]. In situ hybridization with chromosome-specific paint probes assisted in identifying several of the rearrangements formerly designated as marker chromosomes. Although some of the anomalies observed appear unique to this case, others are similar to those previously reported in chordoma.

Aged↗
PubMed1994

Clonal chromosomal abnormalities in osteofibrous dysplasia. Implications for histopathogenesis and its relationship with adamantinoma.

BACKGROUND: The pathogenesis of osteofibrous dysplasia, a rare fibroosseous lesion occurring almost exclusively in the tibia of children younger than 10 years of age, is not known. One theory is that osteofibrous dysplasia results from excessive resorption of bone with fibrous repair of the defect. Alternatively, osteofibrous dysplasia has been considered a congenital lesion or a variant of fibrous dysplasia. It has been hypothesized that osteofibrous dysplasia is a secondary reactive process to adamantinoma. Cytogenetic analysis is one form of investigation that has been instrumental in determining the origin of many disorders. METHODS: Short-term cultures of two separate osteofibrous dysplasia specimens (approximately 1 year apart) from the tibia of an 11-year-old boy and 2 separate specimens (approximately 2 years apart) from the tibia of a 16-year-old boy were cytogenetically examined using standard procedures. Additionally, fluorescence in situ hybridization (FISH) studies were performed on uncultured cells of both specimens of the first patient using an alpha-satellite probe for chromosome 12. RESULTS: Cytogenetic and FISH analysis revealed trisomy 12 in both specimens of the first patient. Trisomy for chromosomes 7, 8, and 22 was seen in both specimens of the second patient. CONCLUSIONS: Osteofibrous dysplasia has not previously been subjected to cytogenetic analysis. Trisomy 7 and 12, however, have been reported in a clonally aberrant adamantinoma, potentially providing further support for a relationship between these two lesions. Most importantly, these findings demonstrate a clonal and possibly neoplastic origin for osteofibrous dysplasia of long bone.

Adolescent↗
PubMed1994

Cytogenetic findings in malignant triton tumor.

Malignant triton tumor is a rare histologic variant of malignant schwannoma that shows both neural and skeletal muscle differentiation. In this study, cytogenetic analysis of a recurrent malignant triton tumor of the forearm from a 26-year-old female and a primary paraspinal malignant triton tumor from a 27-year-old female revealed complex karyotypes displaying multiple numerical and structural abnormalities. Abnormalities shared by both tumors included three copies of chromosome 22 and structural rearrangements of chromosomes 2, 7, and 21 at identical or closely located breakpoints.

Adult↗
PubMed1994

Simultaneous interphase cytogenetic analysis and fluorescence immunophenotyping of dedifferentiated chondrosarcoma. Implications for histopathogenesis.

Cytogenetic analysis of four specimens (biopsy, definitive surgical, and two separately occurring lung metastases) of a dedifferentiated chondrosarcoma with a rhabdomyosarcomatous component revealed clonal karyotypic abnormalities in each. Anomalies seen in all specimens included a structurally aberrant chromosome 17 and extra copies of chromosomes 5, 7, 12, and 20. The derivation of the chromosomally abnormal cells was determined by a combined immunocytochemical/cytogenetic approach that allowed simultaneous assessment of cytogenetic aberrations and immunophenotypic features of individual cells. S-100 protein and desmin antibodies were used to evaluate the chondrosarcomatous and rhabdomyosarcomatous components, respectively. A chromosome 7-specific centromeric probe was used for determination of aneuploidy. In both specimens obtained from the primary lesion, S-100 protein and desmin-positive and -negative aneuploid cells were observed. These findings: 1) suggest that both the chondrocytic and rhabdomyoblastic cells arose from the same abnormal clone, 2) support the theory of a common primitive mesenchymal cell progenitor with the ability to differentiate or express features of more than one line of mesenchymal differentiation, and 3) indicate that the term dedifferentiated may be an inaccurate designation for this neoplasm.

Bone Neoplasms↗
PubMed1993

Biologic and clinical significance of cytogenetic and molecular cytogenetic abnormalities in benign and malignant cartilaginous lesions.

Cartilaginous neoplasms are often histologically and therapeutically challenging. Predicting biologic behavior can be difficult. In this study, 120 nonneoplastic, benign, and malignant cartilaginous lesions from 103 patients were cytogenetically analyzed in a 6-year period after short-term culture. For selected cases, fluorescent in situ hybridization (FISH) techniques using chromosome-specific probes were performed on metaphase/interphase preparations and on paraffin-embedded tissue sections. Clonal abnormalities of chromosomes 2, 3, 5, 7, 8, and 12 were most frequently observed. Involvement of chromosomes 5, 8, and 12 may be etiologically significant because of the gene localizations for the human cartilage link protein, Langer-Giedion syndrome (a rare syndrome characterized by multiple exostoses), and type II collagen (a major component of normal cartilage) respectively, to these three chromosomes. That chromosome 7 abnormalities were observed only in malignant tumors is of diagnostic value. The identity of three marker chromosomes and the significance of trisomy 7 (a finding of controversial meaning), were determined with FISH. That the presence of chromosome aberrations and increasing histologic grade strongly correlated (p = 0.001) is of prognostic importance. Moreover, complex aberrations were observed nearly exclusively in high-grade tumors (p = 0.001). The data show that nonrandom chromosome loci are aberrantly affected in cartilaginous lesions and that these abnormalities may be of significant histopathogenetic consequence. In addition, these chromosome abnormalities appear to be diagnostically and prognostically valuable in classifying and grading chondromatous neoplasms.

Adult↗
PubMed1993

A case report of fibrolipoma with t(12;16)(q13;q24).

Chromosomal analysis of a fibrolipoma of the shoulder of a 55-year-old man showed the following abnormal complement: 46,XY,t(12;16)(q13;q24). Comparison with two previously characterized fibrolipomas showed abnormalities reportedly observed in "classic lipoma." A unique or distinguishing anomaly for fibrolipoma was not detected. Therefore, fibrolipoma appears to be distinct histologically but not cytogenetically.

Chromosomes, Human, Pair 12↗
PubMed1992

Clonal chromosomal abnormalities in desmoid tumors. Implications for histopathogenesis.

Desmoid tumors (aggressive fibromatosis) are regarded as lesions of uncertain histopathogenesis. Cytogenetic analyses of 26 desmoid tumor specimens from abdominal or extraabdominal sites of 22 patients with or without Gardner's syndrome (GS) showed clonal karyotypic abnormalities in 7 cases, random abnormalities in 14 cases, and striking telomeric fusion in 5 cases. Loss of chromosome Y, a reported feature of fibromatosis in penile and palmar locations, was detected as a clonal aberration in two patients. Additionally, involvement of 5q was observed in six patients, two of whom had GS. Clonal interstitial deletions of 5q were observed in three patients, one with and two without GS. These findings confirm a clonal and probable neoplastic origin for desmoid tumor and suggest that abnormalities of the Y chromosome and 5q may be important in the genesis of this neoplasm.

Adolescent↗
PubMed1992

Cytogenetic and pathologic aspects of Ewing's sarcoma and neuroectodermal tumors.

Diagnostic classification of poorly differentiated, round cell, primitive neuroectodermal neoplasms, including Ewing's sarcoma, peripheral neuroepithelioma, Askin's tumor, and esthesioneuroblastoma, is challenging to the surgical pathologist using conventional histopathologic approaches because of very similar and overlapping morphologic and cytologic features. Furthermore, distinguishing these neoplasms from neuroblastoma, embryonal rhabdomyosarcoma, small cell osteogenic sarcoma, and non-Hodgkin's lymphoma can be difficult. This paper describes and reviews the cytogenetic and molecular genetic changes in these tumors and demonstrates how the ability to detect these changes has enabled a greater understanding of the histogenesis, classification, diagnosis, and prognosis of these neoplasms.

Cell Transformation, Neoplastic↗
PubMed1992

Ring chromosome in parosteal osteosarcoma. Clinical and diagnostic significance.

In this study, two specimens of a parosteal osteosarcoma, a rare primary bone neoplasm comprising only 3-6% of all osteosarcomas, were cytogenetically analyzed utilizing standard techniques. In contrast to the complex karyotypes previously reported in osteosarcoma, this particular histologic subtype was characterized by a single chromosomal aberration, a ring chromosome. Ring chromosomes have been described as characteristic for two other low-grade malignant mesenchymal neoplasms, well-differentiated liposarcoma and dermatofibrosarcoma protuberans. We propose that the observation of a ring chromosome in osteosarcoma also correlates with a low-grade malignant potential.

Adolescent↗