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M Debiec-Rychter

Publications and source records attributed to M Debiec-Rychter.

At least 37 records · Page 2Linked to original sources
PubMed2001

Aneurysmal bone cyst of the nose with 17p13 involvement.

We report on a 6-year-old girl with a polypoid mass, filling up the entire right nasal cavity as shown on a magnetic resonance imaging scan. Histologically, the tumor had the characteristics of an aneurysmal bone cyst, which is extremely rare in this location. Cytogenetic analysis disclosed a single (6:17)(p21;p13) translocation, confirming a specific genetic involvement in the development of aneurysmal bone cysts. Fluorescent in situ hybridization analysis mapped the putative gene between the p53 (17p13.1) and the Mieller-Dieker gene (17p13.3) loci.

Bone Cysts, Aneurysmal↗
PubMed2001

Is 4q13 a recurring breakpoint in solitary fibrous tumors?

Solitary fibrous tumor (SFT) is a mesenchymal neoplasm found predominantly in the subpleural region but also in many other body sites. We report a malignant solitary fibrous tumor of the peritoneum with a 47,XY,t(4;9)(q13;p23),+5 karyotype. The chromosome 4q13 breakpoint in the presented and previously published case of pleural solitary fibrous tumor with a 46,XY,t(4;15)(q13;q26) karyotype was further characterized by fluorescence in situ hybridization analysis and localized within the 5-cM interval that was flanked by regions specific to YAC clones 761A7 and 886C11. Chromosome translocations involving chromosome 4q13 may characterize a separate cytogenetic subgroup of SFT.

Aged↗
PubMed2001

Histologic localization of PLAG1 (pleomorphic adenoma gene 1) in pleomorphic adenoma of the salivary gland: cytogenetic evidence of common origin of phenotypically diverse cells.

Pleomorphic adenoma gene 1 (PLAG1), a zinc finger transcription factor gene, is consistently rearranged and overexpressed in human pleomorphic adenomas of the salivary glands with 8q12 translocations. In this report, we describe the immunohistochemical localization of PLAG1 protein in pleomorphic adenomas of the salivary gland and corresponding normal tissue, in relation to cytokeratin, vimentin, and BCL-2 expression. Normal salivary gland tissue was not immunoreactive for PLAG1. In primary pleomorphic adenomas, cells strongly immunoreactive for PLAG1 were detected in the outer layer of tubulo-ductal structures, which are thought to be the origin of cells with bi-directional, epithelial, and mesenchymal phenotypes. In contrast, epithelial cells with abundant cytokeratin in the inner tubulo-ductal structures only sporadically expressed PLAG1. BCL-2 immunoreactivity was found mainly in the cells surrounding the tubulo-ductal structures and in the solid undifferentiated cellular masses, within the areas that had moderate PLAG1 immunoreactivity. The variability of PLAG1 expression in neoplastic cells seemed to reflect the morphologic heterogeneity that correlated with the stage of differentiation of the tumor cells. Immunohistochemical/cytogenetic evaluation of two pleomorphic adenomas with t(3;8)(p21;q12) or t(5;8)(p13;q12) translocations demonstrated the clonal nature of immunophenotypically diverse cells. This finding confirms the theory that pleomorphic adenoma cells share a common single-cell origin, most likely from the epithelial progenitor basal duct cells.

Adenoma, Pleomorphic↗
PubMed2001

Calcifying/ossifying synovial sarcoma shows t(X;18) with SSX2 involvement and mitochondrial calcifications.

AIMS: Synovial sarcoma with extensive calcification and ossification is a rare variant, the ultrastructural, cytogenetic and molecular analysis of which has not been reported previously. METHODS AND RESULTS: A large mass in the shoulder of a 20-year-old male patient led to a deformity of the chest wall, thus supporting the hypothesis that this is a slowly growing variant of synovial sarcoma. Nevertheless, the patient developed metastatic lung disease 7 months after resection. On histology, the monophasic spindle cell proliferation was in several areas obscured by the massive calcification and ossification. Immunohistochemistry showed keratin, epithelial membrane antigen, vimentin and CD99 expression. The cytogenetic analysis revealed a single t(X;18)(p11.2; q11.2), typical for synovial sarcoma. Additional fluorescence in-situ hybridization revealed SSX2 involvement. At the ultrastructural level, prominent needle-shaped intramitochondrial crystals were present, both in the cytoplasm and in the extracellular matrix. CONCLUSION: The presence of the t(X;18) with SSX2 involvement definitively characterizes this tumour as a variant of synovial sarcoma. In addition, the needle-like mitochondrial calcifications give a possible clue to the pathogenesis of the extensive metaplastic ossification and calcification.

Adult↗
PubMed2001

Peripheral primitive neuroectodermal tumor within the spinal epidural space.

A case of an epidural spinal peripheral primitive neuroectodermal tumor (pPNET) in a 13-year-old girl is presented. The tumor was disseminated at the moment of diagnosis, thus only diagnostic oligobiopsy of the epidural mass was performed. Histologically the tumor was composed of small round blue cells. The neoplastic cells expressed MIC2 and features of neural differentiation on immunohistochemical staining (neuron-specific enolase, synaptophysin and NCAM positivity). Fluorescent in situ hybridization (FISH) analysis was performed for the final diagnosis and the translocation t(11;22)(q24;q12) was detected. The present case emphasizes the usefulness of FISH in differential diagnosis of tumors, especially when only routinely fixed material is available.

12E7 Antigen↗
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

[Familial occurrence of nephroblastoma].

Wilms' tumour can develop in ways: sporadic--non-hereditary or familial. Familial Wilms' tumour is not very seldom. It is a form of autosomal dominant segregation and probably low and variable penetration. Up to now it has not been observed in the presence of characteristic genetic changes. Taking into consideration the case of the patient with positive family interview we presented the way of diagnosing and treating the child. Moreover we presented the results of cytogenetic examination and molecular analyses (loss of heterozygosity of WT1 gene and loss of heterozygosity 16 q), which had not shown any changes. We also discussed the actual level of knowledge abut familial form of Wilms' tumour.

Child, Preschool↗
PubMed2000

Common chromosome aberrations in the proximal type of epithelioid sarcoma.

A new case of the proximal type of epithelioid sarcoma with a complex karyotype 70-98 <4N>,XX,-X,-X,+5,i(5)(q10),+7,del(7)(q31),i(8)(q10)x3 approximately 4,del(12)(p13),der(18)ins(18:?) (q11;?)del(18)(p11). ish der(18)ins(18;X)del(18)(p11)(wcp18+,wcpX+),+20,+20,dmin [cp9] is described. Both, dual-color FISH using probes specific for OATLI1/OATL2 genes and RT-PCR analysis excluded the presence of t(X;18), typical for synovial sarcoma. Our case together with the previously published ones suggest that the presence of i(8)(q10), losses of 12p and 18p together with the gain of chromosome 20 may represent a common cytogenetic aberrations in the proximal type of epithelioid sarcoma.

Adolescent↗
PubMed2000

16q heterozygosity loss in Wilms' tumour in children and its clinical importance.

INTRODUCTION: The loss of heterozygosity (LOH) of 16q is a structural change detected in about 20-30% of Wilms' tumour cases. Aberrations which result in deletion of 16q are also found in breast cancer, prostate cancer and liver cancer, where they are connected with a worse prognosis. The hypothesis of a bad prognosis in nephroblastomas with LOH 16q was first formulated by scientists from NWTS (National Wilms Tumor Study) on the basis of 232 cases of Wilms' tumour. However, SIOP studies (International Society of Paediatric Oncology) which included 28 cases of Wilms' tumour, did not show any clinico-pathological correlations with LOH 16q. Therefore, we aimed to evaluate the importance of LOH 16q in relation to clinico-pathological factors in a group of children, treated according to the SIOP criteria. AIMS: The aim of this work was to evaluate the frequency of LOH 16q in sporadic unilateral Wilms' tumour and to study the relationship between LOH 16q and selected patho-clinical parameters. The study comprised 66 children (31 girls and 35 boys) aged from 2 days to 13 years. METHODS: LOH 16q was studied by the examination of polymorphism of marker sequences in the region 16q24. DNA was isolated from paraffin sections of tissue for routine microscopic examination by the microdissection method. The method of study involved the amplification of polymorphic sequences from the 16q24 region by polymerase chain reaction (PCR) and separation of the products of amplification by polyacrylamide gel electrophoresis. The results were the subject of statistical analysis in relation to gender, age of child at first diagnosis, stage of clinical advancement and histological type of tumour. The connection between LOH 16q and recurrences, metastases and death, and failure free survival and absolute survival of children followed-up for over 24 months after nephrectomy were studied. RESULTS: The study revealed a lack of correlation between LOH 16q and gender, however LOH 16q was more frequent in children with Wilms' tumour aged >24 months, P<0.05. Also, LOH 16q was more frequent in tumours classified as clinical stage (CS) II or III than in CS I, P<0.05, but there were no differences in the occurrence of LOH 16q in tumours classified as CS II and CS III. We have found no correlation between LOH 16q and the histological type of tumour. However, LOH 16q has been found three times as frequently in tumours from children who died than in tumours of children who survived, P<0.0024.

Adolescent↗
PubMed2000

Preliminary results of the FRO project: chromosomal abnormalities in primary uveal melanoma.

Uveal melanoma is the most common primary intraocular tumor in adults in the western world. Recent studies indicate that the presence of cytogenetic abnormalities in tumor cells is strongly linked with prognosis. The purpose of this project is the detection of chromosomal abnormalities in a series of frozen tumors (retrospective study) and of fresh tumor tissues (prospective study) and to correlate these results with other prognostic factors and survival.

Adult↗
PubMed1999

Histological localization of acetyltransferases in human tissue.

The localization of human arylamine acetyltransferases (NAT) transcripts was performed by non-isotopic in situ hybridization, utilizing a combination of six NAT1 or NAT2 specific antisense oligonucleotide probes, in order to identify those tissues and organs that might be susceptible to the carcinogenic effects of aromatic amines. The intratissue differences in the level of NAT mRNA were observed: the most abundant NAT2 transcripts were found in hepatocytes, while NAT1 ones dominated in the urothelium and in the colon epithelial cells. The specific NAT1 and NAT2 mRNAs were present also in the epithelial lining of the lung bronchi, the mammary gland and the small intestine epithelial cells, the outer layer of placenta syncytiotrophoblast cells, the kidney tubules, and the pineal gland. Qualitative differences in the sites of mRNA of these two enzymes were seen only in the kidney specimens, in which NAT2 was expressed in both proximal and distal tubules, and the NAT1 was detected only in the former ones.

Acetyltransferases↗
PubMed1999

Cytogenetic changes in two cases of subependymal giant-cell astrocytoma.

Cytogenetic analysis of subependymal giant-cell astrocytomas (SEGAs) from two patients presenting the clinical symptoms of tuberous sclerosis complex (TSC) revealed clonal chromosomal changes, resulting in the partial loss of chromosome 22q in both tumors. Immunohistochemically, tumors exhibited features of glial differentiation, while ultrastructural studies identified the characteristic paracrystalline inclusions within the tumor cells. To our knowledge, it is the first cytogenetic description of SEGAs associated with TSC.

Brain Neoplasms↗
PubMed1999

N-Acetyltransferase expression and DNA binding of N-hydroxyheterocyclic amines in human prostate epithelium.

Intact prostate epithelial cells prepared from benign prostatic hypertrophy tissues from two patients were incubated for 2 h with N-hydroxy derivatives of 2-amino-1-methyl-6-phenylimidazo[4, 5-b]pyridine (N-OH-PhIP) or 2-amino-3,8-dimethylimidazo[4, 5-f]quinoxaline (N-OH-MeIQx). (32)P-post-labeling analysis detected PhIP and MeIQx adducts in the DNA of these cells but not in the untreated control. Adduct levels were approximately 100 times greater in N-OH-PhIP- than in N-OH-MeIQx-treated cells. Repair synthesis of DNA was observed in cells, prepared from two additional patients, treated for 24 h with these carcinogens and was greater for N-OH-PhIP than for N-OH-MeIQx. PhIP, MeIQx and their nitro derivatives did not produce repair synthesis of DNA in this system. The difference in the activity of N-OH-PhIP and N-OH-MeIQx may be due to their stability, since N-OH-MeIQx decomposed rapidly in neutral solution. Transcripts of NAT1 and NAT2 were detected by an in situ hybridization method in prostate epithelial cells, but were absent from stromal tissues. These results suggest that PhIP may be a potential carcinogen for human prostate, since cooked meats, which contain this heterocyclic amine, have been associated with human prostate cancer.

Arylamine N-Acetyltransferase↗
PubMed1999

Malignant fibrous histiocytomas and H-ras-1 oncogene point mutations.

AIMS: To investigate the types and the frequencies of H-ras-1 gene mutations in malignant fibrous histiocytomas. METHODS: Thirty five samples of malignant fibrous histiocytoma tissue were searched for point mutations within "hot spot" codons 12 and 13 of the H-ras-1 oncogene by the specific "nested" polymerase chain reaction followed by restriction fragment length polymorphism (PCR-RFLP) and a direct cycle sequencing procedure. RESULTS: In contrast to previous reports, none of the tumours contained a point mutation or any other changes within or around the hot spot gene sequences. CONCLUSIONS: These data indicate that H-ras-1 oncogenic activation is not required in the molecular pathway of malignant fibrous histiocytoma formation and cannot be used as a discriminating factor for diagnostic sarcoma typing.

Exons↗
PubMed1999

Atypical chronic myelogenous leukemia following immunosuppressive therapy for severe aplastic anemia.

Late clonal complications of aplastic anemia (AA) such as acute leukemia, myelodysplastic syndromes or paroxysmal nocturnal hemoglobinuria have been recognized for a long time. To our knowledge, chronic myelogenous leukemia (CML) as a late complication of severe aplastic anemia has as yet not been reported. We report here a case of AA treated successfully with antilymphocytic globulin and cyclosporin in whom Ph1 negative, BCR/ABL negative CML developed 8 years after diagnosis of AA. This case of atypical, secondary CML was refractory to treatment with interferon alpha and hydroxyurea.

Adult↗
PubMed1999

Expression of P53, MDM2 and Ki-67 antigens in soft tissue sarcomas.

The expression of P53 and MDM2 proteins was examined by immunohistochemistry in 115 soft-tissue sarcomas (STSs), including 32 malignant peripheral nerve sheath tumours, 27 liposarcomas, 18 leiomyosarcomas, 16 synovial sarcomas, 14 fibrosarcomas and 8 dermatofibrosarcomas, to investigate their possible association with clinicopathologic features and proliferative rate. Positivity for P53 and MDM2 was found in 9.7% and 28.1% tumours, respectively. The fraction of P53 and MDM2 positive tumours was the highest in leiomyosarcomas (16.7% and 17.2%, respectively) and the lowest in dermatofibrosarcomas (0% and 4.3%, respectively). Overall, P53(-)/MDM2(+) phenotype predominated (20.2%), while 7.9% of tumours were both P53 and MDM2 positive, and 1.8% of tumours were only P53 positive. P53 accumulation was associated with a high histological malignancy grade and a higher proliferative rate. MDM2 immunoreactivity was revealed in tumours of all malignancy grades and there was no association between MDM2 positivity and tumours proliferative activity. These results suggest that P53 overexpression underlays rather late events in the oncogenesis of STSs, which might be a determinant of their proliferative rate. In contrast, MDM2 deregulation seems to be an early rather than a late event in STSs, which may occur without involving stabilization and inactivation of P53 gene.

Adult↗
PubMed1999

A comparative study of P53/MDM2 genes alterations and P53/MDM2 proteins immunoreactivity in soft-tissue sarcomas.

In the present study, the expression of P53 and MDM2 proteins were examined in 94 soft-tissue sarcomas (35 malignant fibrohistiocytomas, 15 neurosarcomas, 14 liposarcomas, 13 leiomyosarcomas, 11 fibrosarcomas and 6 dermatofibrosarcomas) by immunohistochemistry. The immunohistochemical findings were correlated with P53 mutation analysis using PCR-SSCP, PCR-HDF and direct sequencing, and MDM2 amplification studies by differential PCR. P53 immunopositivity was found in 25 out of 94 (26.6%) cases. Alterations of the P53 gene were detected in 12 (12.8%) tumors; eight of these tumors revealed P53 immunoreactivity. A high number of P53 positive and P53 mutated tumors were histologically defined as poorly differentiated G3 (64.0% and 75.0%, respectively). MDM2 immunopositivity was revealed in 36 out of 94 (38.3%) cases. MDM2 amplification occurred in 17 tumors (18.1%); only nine of these tumors exhibited MDM2 immunoreactivity. Overall, MDM2 positivity was not associated with MDM2 amplification in 27 out of 94 tumors (28.7%). There was no significant correlation between MDM2 overexpression and histological grade. However, when the samples were stratified by immunophenotype, the majority of tumors (52.5%) with isolated MDM2 overexpression (dissociated from P53 positivity) were defined histologically as low grade (G1 + G2). These results support the notion that besides P53 alterations, MDM2 gene deregulation seems to be an important event in sarcomas evolution. Additionally, the mechanism of MDM2-mediated degradation of P53 protein, without involving stabilization and inactivation of P53 gene, should be considered for better understanding of all features of tumor progression processes.

Adult↗