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J V Bovée

Publications and source records attributed to J V Bovée.

17 recordsLinked to original sources
PubMed2001

Chondrosarcoma is not characterized by detectable telomerase activity.

Reactivation of telomerase, an enzyme which elongates human telomeres, is associated with cell immortilization. In approximately 90% of malignant tumours telomerase activity can be demonstrated, whereas in benign tumours it is mostly absent. Chondrosarcomas are relatively rare malignant cartilaginous neoplasms. A small number of chondrosarcomas located centrally in bone arise secondarily to an enchondroma, while the majority of chondrosarcomas developing from the surface arise within the cartilage cap of an osteochondroma. The histological distinction between a benign lesion and low-grade chondrosarcoma is generally considered difficult. To investigate whether the progression towards chondrosarcoma is characterized by reactivation of telomerase activity, this study determined telomerase activity in ten enchondromas, five osteochondromas, and 37 chondrosarcomas using the TRAP assay. In all tumour samples except one, telomerase activity was absent. By adding tumour lysates to the positive control, an increasing inhibition of telomerase activity was found with an increasing chondroid matrix, suggesting that it may contain inhibitory factors. Inhibition due to endogenous RNAse or Taq-polymerase inhibitors was excluded. The lack of detectable telomerase activity in the high-grade component of a dedifferentiated chondrosarcoma without matrix favours the possibility that telomerase is truly absent. Either its true absence or inhibitory effects disabling telomerase detection exclude the telomerase TRAP assay as a diagnostic tool in the differential diagnosis of benign and low-grade malignant cartilaginous tumours.

Biomarkers, Tumor↗
PubMed2001

Chromosome 9 alterations and trisomy 22 in central chondrosarcoma: a cytogenetic and DNA flow cytometric analysis of chondrosarcoma subtypes.

Chondrosarcomas are malignant cartilaginous tumors. Most are located in the medullar cavity (central chondrosarcoma), and a minority develop in a preexisting osteochondroma (peripheral chondrosarcoma). The authors present karyotypes for 37 central, peripheral, juxtacortical, and dedifferentiated chondrosarcomas. Using loss of heterozygosity (LOH) analysis and DNA flow cytometry, the authors previously showed that central and peripheral chondrosarcomas probably evolve by different genetic mechanisms. Peripheral chondrosarcoma is characterized by genetic instability, as was previously shown by a high percentage of LOH and a broad range in DNA ploidy. The authors now show that all peripheral chondrosarcomas tested are aneuploid, combined with many nonspecific chromosomal aberrations. Two juxtacortical chondrosarcomas showed normal chromosome numbers combined with limited structural alterations, substantiating that juxtacortical and peripheral chondrosarcomas are two clinicopathologically different entities with a different genetic background. Central chondrosarcomas were previously found to be peridiploid with limited LOH, most frequent at 9p21. In the current study, chromosome 9 was involved in five of seven central chondrosarcomas compared with only one of four peripheral chondrosarcomas. Three central tumors showed involvement of the 9pl2-22 region, suggesting an important role for chromosome 9 in the oncogenesis of central chondrosarcoma. Moreover, trisomy 22 was found in four central chondrosarcomas only.

Adolescent↗
PubMed2001

High quality RNA isolation from tumours with low cellularity and high extracellular matrix component for cDNA microarrays: application to chondrosarcoma.

AIMS: High quality RNA isolation from cartilaginous tissue is considered difficult because of relatively low cellularity and the abundance of extracellular matrix rich in glycosaminoglycans and collagens. Given the growing interest and technical possibilities to study RNA expression at a high throughput level, research on tissue with these characteristics is hampered by the lack of an efficient method for obtaining sufficient amounts of high quality RNA. METHODS: This paper presents a robust protocol combining two RNA isolation procedures, based on a combination of Trizol and RNA specific columns, which has been developed to obtain high molecular weight RNA from fresh frozen and stored tissue of normal cartilage and cartilaginous tumours. Using this method, RNA was isolated from normal cartilage, peripheral chondrosarcoma, and central chondrosarcoma. RESULTS: The yields ranged from 0.1 to 0.5 microg RNA/mg tissue. RNA isolated with this method was stable and of high molecular weight. RNA samples from normal cartilage and from two chondrosarcomas isolated using this method were applied successfully in cDNA microarray experiments. The number of genes that give interpretable results was in the range of what would be expected from microarray results obtained on chondrosarcoma cell line RNA. Signal to noise ratios were good and differential expression between tumour and normal cartilage was detectable for a large number of genes. CONCLUSION: With this newly developed isolation method, high quality RNA can be obtained from low cellular tissue with a high extracellular matrix component. These procedures can also be applied to other tumour material.

Bone Neoplasms↗
PubMed2000

Near-haploidy and subsequent polyploidization characterize the progression of peripheral chondrosarcoma.

Chondrosarcomas are malignant cartilaginous tumors arising centrally in bone (central chondrosarcoma), or secondarily within the cartilaginous cap of osteochondroma (peripheral chondrosarcoma). We previously used DNA flow cytometry to demonstrate that near-haploidy is relatively frequent in peripheral chondrosarcomas. We performed fluorescence in situ hybridization (FISH) to interphase nuclei using centromeric probes, a genome wide loss of heterozygosity (LOH) analysis, and comparative genomic hybridization on five peripheral chondrosarcomas. We demonstrated near-haploidy in two low-grade tumors with only one copy and LOH of most chromosomes. Few chromosomes are disomic, with retention of heterozygosity and overrepresentation at comparative genomic hybridization. One tumor contains both a near-haploid clone with chromosomes in monosomic and disomic state, and an exactly duplicated clone. Two high-grade tumors clearly demonstrate polyploidization because most chromosomes show LOH and two copies at FISH, whereas few chromosomes have four copies with retention of heterozygosity. Using DNA from a relative, we demonstrate that chromosome loss is random regardless of parental origin. Using FISH on paraffin slides, we exclude near-haploidy to result from meiosis-like division in binucleated cells, characteristic for chondrosarcoma. In conclusion, our results indicate that near-haploidy characterizes the progression from osteochondroma toward low-grade chondrosarcoma. Moreover, further progression toward high-grade chondrosarcoma is characterized by polyploidization.

Adult↗
PubMed2000

Up-regulation of PTHrP and Bcl-2 expression characterizes the progression of osteochondroma towards peripheral chondrosarcoma and is a late event in central chondrosarcoma.

Chondrosarcomas are malignant cartilage-forming tumors arising centrally in bone (central chondrosarcoma) or within the cartilaginous cap of osteochondroma (peripheral chondrosarcoma). For hereditary multiple osteochondromas, two responsible genes, EXT1 and EXT2, have been cloned. Their recently elucidated role in heparan sulfate biosynthesis and Hedgehog diffusion leads to the hypothesis that EXT inactivation affects fibroblast growth factor (FGF) and Indian Hedgehog (IHh)/parathyroid hormone-related peptide (PTHrP) signaling, two important pathways in chondrocyte proliferation and differentiation. The expression of PTHrP, PTHrP-receptor, Bcl-2, FGF2, FGFR1, FGFR3, and p21 is investigated by immunohistochemistry in osteochondromas (n = 24) and peripheral (n = 29) and central (n = 20) chondrosarcomas. IHh/PTHrP and FGF signaling molecules are mostly absent in osteochondromas. Although no somatic EXT mutations were found in sporadic osteochondromas, the putative EXT downstream targets are affected similarly in sporadic and hereditary tumors. In chondrosarcomas, re-expression of FGF2, FGFR1, PTHrP, Bcl-2, and p21 is found. Expression levels increase with increasing histological grade. Up-regulation of PTHrP and Bcl-2 characterizes malignant transformation of osteochondroma because PTHrP and Bcl-2 expression is significantly higher in borderline and grade I peripheral chondrosarcomas compared with osteochondromas. In contrast, up-regulation of PTHrP and Bcl-2 seems to be a late event in central cartilaginous tumorigenesis because expression is mainly restricted to high-grade central tumors.

Adolescent↗
PubMed2000

Malignant progression in multiple enchondromatosis (Ollier's disease): an autopsy-based molecular genetic study.

Multiple enchondromatosis (Ollier's disease) is a nonhereditary disease characterized by multiple central (medullary) cartilaginous bone tumors of unknown pathogenesis. It usually involves the extremities with a unilateral predominance, and sarcomatous transformation may occur. We report an autopsy-based genetic study of a 34-year-old man presenting in early adolescence with multiple enchondromas of the extremities, predominantly left-sided, compatible with Ollier's disease. Twelve years after presentation, malignant transformation to a high grade chondrosarcoma occurred in a tibial enchondroma. The patient died after widespread metastatic disease. Loss of heterozygosity (LOH), in the tibial chondrosarcoma and its metastases, was identified exclusively on chromosome bands 13q14 and 9p21, while being absent in the femoral enchondroma analyzed. Similarly, p53 overexpression was identified immunohistochemically in the tibial chondrosarcoma and its metastases, while being absent in the femoral enchondroma; LOH at 17p13 however, was not demonstrable. It is hypothesized that inactivation of putative tumor suppressor genes at 9p21 and 13q14, and overexpression of p53, identified in the chondrosarcoma and its metastases, but absent in enchondroma, may be related to sarcomatous transformation in Ollier's disease.

Adult↗
PubMed2000

An update of diagnostic strategies using molecular genetic and magnetic resonance imaging techniques for musculoskeletal tumors.

Rheumatologists may be incidentally confronted by bone and soft tissue lesions presenting in and around joints that require early recognition and appropriate referral. The diagnostic and therapeutic management of patients with musculoskeletal tumors is critically dependent on a multidisciplinary approach. Advances, particularly in the fields of histopathology, molecular (cyto)genetics and radiologic imaging techniques, have resulted in significant improvements in reaching a correct (differential) diagnosis, essential for implementing optimal treatment modalities. Magnetic resonance imaging is becoming increasingly important in planning preoperative and postoperative management strategies, and should precede all invasive procedures. Improvements in the fields of immunohistochemistry, together with the realization that certain tumor groups may be associated with specific genetic alterations, has significantly improved diagnostic accuracy. Additionally, the presence of certain genetic alterations within the tumoral genome have been found to be of prognostic value, and the hereditary context recognized for a number of specific bone and soft tissue tumors should be taken into account in the management of a patient with such a neoplasm. It is envisaged that an increasing understanding of the molecular biology and histogenesis of individual musculoskeletal tumor types will lead to tailor-made therapeutic options and consequently prognostic improvements. This update serves to highlight some important recent developments in fundamental and diagnostic aspects of musculoskeletal tumors.

Biopsy↗
PubMed1999

Chondrosarcoma of the phalanx: a locally aggressive lesion with minimal metastatic potential: a report of 35 cases and a review of the literature.

BACKGROUND: Enchondroma is the most common primary benign bone tumor of the hand, especially the phalanges, whereas chondrosarcoma is uncommon at this site. Although phalangeal chondrosarcoma may have ominous histologic features, its biologic behavior is relatively indolent. METHODS: Thirty-five cases of phalangeal lesions previously diagnosed as chondrosarcoma were studied. Histologic and tumor-biologic parameters (Ki-67 and p53 immunohistochemistry) were investigated and correlated with clinical behavior. RESULTS: All cases were characterized by unequivocal malignant histologic features (Grade 2 or higher) or Grade 1 malignant histologic features combined with the presence of cortical destruction and soft tissue extension. The median age of the patients at the time of diagnosis was 67 years (range 21-87 years), with a slight female predominance. Occurrence in the hand was more common than in the foot, with the proximal phalanx affected most often. Treatment varied from local therapy (curettage or local excision) in 16 patients to amputation or exarticulation in 19 cases. Follow-up ranged from 8-432 months for 28 patients. Ten of 15 tumors treated by local therapy recurred whereas none of 13 tumors treated by radical surgery recurred. The median survival was 20.8 years; none of 28 patients developed metastases nor died of disease. Both the type of treatment and localization in the proximal phalanx were associated independently with local recurrence. CONCLUSIONS: Phalangeal chondrosarcoma behaves as a locally aggressive lesion and, in contrast to chondrosarcomas located elsewhere, rarely metastasizes. Treatment is indicated only because of its locally destructive growth. The authors believe that given the excellent survival data, curettage with adequate follow-up should be considered as the treatment of choice if technically feasible, especially in those cases in which amputation would lead to a significant loss of hand function.

Adult↗
PubMed1999

Molecular genetic characterization of both components of a dedifferentiated chondrosarcoma, with implications for its histogenesis.

Dedifferentiated chondrosarcoma is defined as a high-grade, anaplastic sarcoma adjacent to a low-grade malignant cartilage-forming tumour. Controversy remains as to whether the anaplastic and cartilaginous components are derived from a common precursor cell, or whether they represent separate genotypic lineages (collision tumour). Both components of a case of dedifferentiated chondrosarcoma were therefore separately investigated by loss of heterozygosity (LOH) analysis, comparative genomic hybridization (CGH), DNA flow cytometry, and p53 analysis. Both showed p53 overexpression and an identical somatic 6 bp deletion in exon 7 of p53. Combination of the CGH and LOH results revealed that both components had lost the same copy of chromosome 13. These results provide compelling evidence in this case for a common origin, instead of the 'collision tumour' theory. Certain genotypic alterations were not shared. The anaplastic component showed severe aneuploidy, LOH at additional loci, and amplification and deletion of several chromosome parts. In contrast, the cartilaginous component had lost chromosomes 5, 22, 17p and part of 16p and revealed an amplification of 17q. The LOH and CGH results further demonstrated that the two components had lost a different copy of chromosome 4. Thus, a substantial number of genetic alterations have occurred after the diversion of the two components, indicating that the separation of the two clones, derived from a single precursor, was a relatively early event in the histogenesis of this case of dedifferentiated chondrosarcoma.

Autoradiography↗
PubMed1999

EXT-mutation analysis and loss of heterozygosity in sporadic and hereditary osteochondromas and secondary chondrosarcomas.

Osteochondromas occur as sporadic solitary lesions or as multiple lesions, characterizing the hereditary multiple exostoses syndrome (EXT). Approximately 15% of all chondrosarcomas arise within the cartilaginous cap of an osteochondroma. EXT is genetically heterogeneous, and two genes, EXT1 and EXT2, located on 8q24 and 11p11-p12, respectively, have been cloned. It is still unclear whether osteochondroma is a developmental disorder or a true neoplasm. Furthermore, it is unclear whether inactivation of both alleles of an EXT gene, according to the tumor-suppressor model, is required for osteochondroma development, or whether a single EXT germline mutation acts in a dominant negative way. We therefore studied loss of heterozygosity and DNA ploidy in eight sporadic and six hereditary osteochondromas. EXT1- and EXT2-mutation analysis was performed in a total of 34 sporadic and hereditary osteochondromas and secondary peripheral chondrosarcomas. We demonstrated osteochondroma to be a true neoplasm, since aneuploidy was found in 4 of 10 osteochondromas. Furthermore, LOH was almost exclusively found at the EXT1 locus in 5 of 14 osteochondromas. Four novel constitutional cDNA alterations were detected in exon 1 of EXT1. Two patients with multiple osteochondromas demonstrated a germline mutation combined with loss of the remaining wild-type allele in three osteochondromas, indicating that, in cartilaginous cells of the growth plate, inactivation of both copies of the EXT1 gene is required for osteochondroma formation in hereditary cases. In contrast, no somatic EXT1 cDNA alterations were found in sporadic osteochondromas. No mutations were found in the EXT2 gene.

Adolescent↗
PubMed1999

Diagnostic and prognostic implications of the unfolding molecular biology of bone and soft tissue tumours.

Sarcomas account for approximately 1-2% of human malignant disease and are relatively uncommon. Histopathological study of these mesenchymal tumours at light microscopic and ultrastructural level may not always provide an unambiguous diagnosis. It has become apparent with the identification of increasing numbers of tumour specific genetic alterations that (cyto) genetic evaluation could become a very helpful adjunct to histopathological assessment in reaching a correct diagnosis. Thus, once the different tumour types can be accurately identified and classified, more meaningful clinical trials can be initiated to evaluate and select optimal methods of management. In addition, an increasing awareness and understanding of the molecular changes associated with, and the genetic variability in, the various tumour groups is beginning to provide important new information about clinical progression and prognosis.

Adolescent↗
PubMed1999

Loss of heterozygosity and DNA ploidy point to a diverging genetic mechanism in the origin of peripheral and central chondrosarcoma.

Chondrosarcomas are malignant cartilaginous tumors arising centrally in bone (central chondrosarcoma), or secondarily within the cartilaginous cap of a hereditary or sporadic exostosis (peripheral chondrosarcoma). Loss of heterozygosity (LOH) was studied by microsatellite analysis at the loci harboring the EXT genes (implicated in hereditary multiple exostoses), the EXT-like genes, and at 9p21, 13q14, 17p13, and chromosome 10. Nineteen of 20 peripheral chondrosarcomas showed LOH at all loci tested, while only 3 of 12 central chondrosarcomas exhibited LOH, restricted to 9p21, 10, 13q14, and 17p13. LOH at 9p21 did not appear to involve the CDKN2A gene, as assessed by SSCP analysis. DNA flow cytometry demonstrated a wide variation in the ploidy status in peripheral chondrosarcomas (DNA indexes, 0.56-2.01), whereas central chondrosarcomas were predominantly peridiploid. Near-haploidy found in peripheral chondrosarcomas could explain part of the high LOH percentages. Ki-67 immunohistochemistry suggested a higher proliferation rate in peripheral chondrosarcomas. Our results indicate that peripheral chondrosarcomas, arising secondarily to an exostosis, may obtain genetic alterations during malignant transformation, with subsequent genetic instability as demonstrated by a high percentage of LOH and a wide variation in ploidy status. In contrast, peridiploidy and a low percentage of LOH in central tumors suggest that a different oncogenic molecular mechanism may be operative.

Adolescent↗
PubMed1998

Expression of growth factors and their receptors in adamantinoma of long bones and the implication for its histogenesis.

Adamantinoma of long bones is a rare bone tumour with (immuno-) histological features of epithelial cells, surrounded by various amounts of osteofibrous tissue. Recent studies have indicated that cells with an epithelial phenotype are most probably the malignant element. There is still debate as to whether the fibrous part should be designed as a benign neoplastic element of a biphasic tumour or as a reactive non-neoplastic tissue next to an epithelioid bone tumour. The expression of fibroblast growth factor type 2 (FGF-2), epidermal growth factor (EGF), and their respective receptors FGFR-1 and EGFR, as well as the proliferation marker Ki-67, was studied in both constituents of adamantinoma in serial sections of 25 cases by immunohistochemistry. Expression of FGF-2 and its receptor was present in both constituents of adamantinoma, but predominated in the epithelial component. Expression of EGF and its receptor was restricted to the epithelial component of adamantinoma. Comparing osteofibrous dysplasia (OFD)-like adamantinoma with classic epithelial cell-rich adamantinoma, the expression of FGF-2, EGF, and EGFR was more intense and in a higher percentage of cells in classic adamantinoma. Proliferative activity was found nearly exclusively in the epithelial component. These data further substantiate the hypothesis that epithelial cells constitute the proliferating tumour cell population responsible for the malignant behaviour of adamantinoma. The data indicate that during progression, the epithelial cells acquire expression of FGF-2, EGF, and EGFR, accompanied by a higher proliferative activity. Within the epithelial cell population, there exists an autocrine pathway of growth stimulation. Furthermore, these data point to an interaction between the epithelial and fibrous components, in which the epithelial cells additionally stimulate fibrous cell growth via a paracrine pathway involving FGF-2.

Ameloblastoma↗
PubMed1998

Ring chromosome 4 as the sole cytogenetic anomaly in a chondroblastoma: a case report and review of the literature.

Chromosome analysis of a chondroblastoma of the right distal femur in a 31-year-old male patient revealed a ring chromosome 4 in approximately one-third of the analyzed cells. The remaining cells had a normal karyotype. These findings were subsequently confirmed by fluorescence in situ hybridization (FISH) with a chromosome-4-specific library. FISH with cosmids pC847.351 (4p16.3) and cT171 (4q35) revealed that fewer than 300 kilobase pairs (kbp) are deleted. To our knowledge, ring chromosome 4 has never been reported in this type of neoplasm. There are, however, several reports of chondroblastoma with other chromosome abnormalities, but the relation of these anomalies to this tumor specifically is unclear. In this report, we also provide a review of the literature concerning cytogenetic studies in chondroblastoma. The possible significance of ring chromosome 4 in this type of tumor is discussed.

Adult↗
PubMed1997

[Molecular biology diagnosis of tumors of the musculoskeletal system].

It is sometimes difficult to make an unequivocal diagnosis of tumours of bone and soft tissue based upon classical morphology alone, which has led to an increased use of additional diagnostic tools. In the past decade new techniques have become available, based on tumour specific genetic alterations, for instance chromosomal translocations. With the cloning of the translocation breakpoints and the identification of the genes involved, the reverse transcriptase polymerase chain reaction (RT-PCR) detection of the fusion gene has become an important diagnostic test. Also, non-tumour specific genetic alterations with prognostic value can be detected.

Bone Diseases↗
PubMed1995

Identification of an EWS-pseudogene using translocation detection by RT-PCR in Ewing's sarcoma.

The presence of a t(11;22)(q24;q12) translocation is one of the characteristic features of the Ewing family of tumors. The detection of the fusion gene product by RT-PCR using primers at both sides of the breakpoints has been advocated as a diagnostic tool. By applying this technique appropriate internal controls are required. We found that the use of normal non-rearranged EWS mRNA as an internal control for RNA quality may lead to conflicting data. We obtained PCR products of the expected size for the normal EWS mRNA in both RNA and DNA samples, suggesting, the existence of one or more EWS pseudogenes. A 109 bp sequence at the 5' end of this PCR-product contained a correctly spliced exon junction and was 97% homologous to the EWS cDNA sequence. Similarly two such junctions were found in a 346 bp sequence of the 3' end, which was 89% homologous. Hence EWS should not be used as an internal control for the RNA quality in a RT-PCR based test for the presence of the translocation.

Base Sequence↗