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F Mertens

Publications and source records attributed to F Mertens.

At least 19 recordsLinked to original sources
PubMed1999

Different patterns of chromosomal imbalances in metastasising and non-metastasising primary breast carcinomas.

In an attempt to identify chromosomal abnormalities that may be associated with a metastatic phenotype, we investigated the pattern of chromosomal gains and losses in 66 node-positive and 63 node-negative primary breast carcinomas. For both subgroups of tumours, losses were more common than gains and the losses were most often the result of structural aberrations. The exceptions were the long arm of chromosome 1, and chromosomes 7, 8, 12, 18 and 20, which were more often gained than lost. Node-negative tumours were preferentially characterised by loss of 6q10-21 and loss of 16q, whereas loss of chromosome 18 was significant for node-positive tumours. Other aberrations that tended to be associated with one of the phenotypes, though not statistically significant, were gain of chromosome 18 and loss of chromosome 10 in node-negative tumours, and gain of chromosome 14 and loss of 12p in node-positive tumours. Our data show that there are differences among the genetic lesions present in node-negative and node-positive breast tumours. Int. J. Cancer (Pred. Oncol.) 84:370-375, 1999.

Breast Neoplasms↗
PubMed1999

Cytogenetic aberrations in Ewing sarcoma: are secondary changes associated with clinical outcome?

BACKGROUND: Ewing sarcoma is associated with a nonrandom pattern of primary and secondary chromosomal aberrations. Whereas the finding of rearrangements of chromosome 22, usually in the form of a balanced translocation t(11;22)(q24;q12), is important diagnostically, nothing is known about the potential prognostic impact of the secondary chromosomal aberrations. PROCEDURE: During a 1 3-year-period, short-term cultured tumor samples from 21 children and young adults with Ewing sarcoma were cytogenetically analyzed successfully. RESULTS: Clonal chromosome aberrations were detected in 18 patients, 17 of whom had the characteristic t(11;22)(q24;q12) or variants thereof. The most frequent secondary change was +8, followed by +12, +2, +5, +9, +15, and gain of material from the long and short arms of chromosome 1. The only recurrent secondary change that was restricted to tumors from the ten patients that were dead at latest follow-up was gain of 1q material. Furthermore, all three patients with tumors with chromosome numbers over 50 had died, and the only patient with a tumor karyotype lacking chromosome 22 rearrangement was alive without evidence of disease. CONCLUSIONS: These data and previously published results indicate that the karyotypic pattern not only may be of diagnostic significance but also may be important prognostically.

Adolescent↗
PubMed1999

The structure and dynamics of ring chromosomes in human neoplastic and non-neoplastic cells.

Acquired ring chromosomes have been found in most types of human neoplasia, with a frequency approaching 10% in malignant mesenchymal tumours. In this study, the composition and dynamics of ring chromosomes were analysed in eight cases of acute myelogenous leukaemia, 17 solid tumours, and five cases with constitutional rings. Chromosomal banding and fluorescence in situ hybridisation were performed to determine the content and the structural heterogeneity of the rings. Telomeric repeats were detected using peptide nucleic acid probes or primed in situ labelling, whereas centromeric activity was evaluated by detection of kinetochore proteins. Mitotic instability was assessed by the frequency of anaphase bridges. The results suggest that human ring chromosomes can be structurally and functionally divided into two categories. In the first of these, size variation is minimal and rearrangement at cell division is uncommon. The majority of such rings contain subtelomeric sequences. Constitutional ring chromosomes and most rings in leukaemias belong to this group, whereas only a few mesenchymal tumours exhibit rings of this type. The second category consists of rings with amplified sequences, primarily from chromosome 12, characteristically occurring in atypical lipomatous tumours and other subtypes of low or borderline malignant mesenchymal neoplasms. Variation in size and number is extensive, and breakage-fusion-bridge events occur at a high frequency. Abnormalities in pericentromeric sequences are common and, in some cases, kinetochores assemble in the absence of alphoid DNA. We conclude that it is not only the ring structure per se or the neoplastic nature of the host cell that determines ring instability, but probably also the functional role of the genes carried in the ring.

Abnormalities, Multiple↗
PubMed1999

Hibernomas are characterized by homozygous deletions in the multiple endocrine neoplasia type I region. Metaphase fluorescence in situ hybridization reveals complex rearrangements not detected by conventional cytogenetics.

Hibernomas are benign tumors of brown fat, frequently characterized by aberrations of chromosome band 11q13. In this study, the chromosome 11 changes in five hibernomas were analyzed in detail by metaphase fluorescence in situ hybridization. In all cases, complex rearrangements leading to loss of chromosome 11 material were found. Deletions were present not only in those chromosomes that were shown to be rearranged by G-banding, but in four cases also in the ostensibly normal homologues, resulting in homozygous loss of several loci. Among these, the gene for multiple endocrine neoplasia type I (MEN1) was most frequently deleted. In addition to the MEN1 deletions, heterozygous loss of a second region, approximately 3 Mb distal to MEN1, was found in all five cases, adding to previous evidence for a second tumor suppressor locus in 11q13.

Adult↗
PubMed1999

Correlation between clinicopathological features and karyotype in spindle cell sarcomas. A report of 130 cases from the CHAMP study group.

Soft-tissue tumors have proved to be a fruitful area for the identification of reproducible cytogenetic aberrations, especially among pediatric round-cell sarcomas and lipomatous tumors. Thus far, however, data regarding sarcomas of monomorphic spindle cell type have been limited and somewhat disappointing, with the notable exception of synovial sarcoma. As part of an ongoing international collaborative study, 130 karyotyped spindle-cell sarcomas were reviewed and classified histologically, without knowledge of the clinical and karyotypic data, with the aim of identifying objective correlations between morphology, karyotype, and clinical parameters. Clonal chromosomal abnormalities were identified in 82 cases studied (63%), but only in the group of synovial sarcomas was there clear correlation between the cytogenetic findings, in the form of a consistent t(X;18)(p11;q11), and morphology. Among leiomyosarcomas (41 cases) and malignant peripheral nerve sheath tumors (MPNSTs; 27 cases) as well as in individual examples of rarer entities, there was a general tendency for karyotypic complexity associated with frequent loss or rearrangement of chromosome arms 1p, 10p, 11q, 12q, 17p, and 22q. Rearrangements of 17q (the region of the NF1 gene) were seen in 9/27 (33%) of MPNSTs. Among nine cases of solitary fibrous tumor (in which previous cytogenetic data are very limited) no consistent aberrations were identified. We conclude that, with the exception of synovial sarcoma, most spindle-cell sarcomas share with pleomorphic sarcomas the tendency for karyotypic complexity. There was no indication (in most of these lesions) that detectable cytogenetic aberrations could either facilitate their diagnosis or help to determine prognosis. There is a clear need to further study and understand the significance of multiple chromosomal abnormalities in this group of mesenchymal neoplasms with the particular goal of determining their role in the process of tumor development.

Adolescent↗
PubMed1999

Multiple polysomies in breast carcinomas: preferential gain of chromosomes 1, 5, 6, 7, 12, 16, 17, 18, and 19.

Chromosome G-banding analysis of metaphase cells from 16 primary breast carcinomas revealed the presence of multiple polysomies in near-diploid as well as in polyploid cells. Chromosome 17 was preferentially gained in 7 tumors, followed in frequency by chromosomes 1, 12, and 19 (5 tumors each), and chromosomes 5, 6, 7, 16, and 18 (4 tumors each). Eleven of the 16 carcinomas had, apart from the clones exhibiting the numerical gains, other unrelated clones. Nine of these 11 cases had clones with structural chromosome aberrations, 5 of which had structural aberrations involving the short arm of chromosome 3. The biologic significance, if any, of this seemingly nonrandom coexistence of multiple polysomies with structural aberrations of 3p is at present not known. The pattern of numerical chromosome aberrations observed in the present study is comparable to previous results from fluorescence in situ hybridization (FISH) studies, with the use of centromeric probes on interphase cells. However, unlike FISH studies, which have been focused on chromosomes 1, 3, 7, 8, 11, 16, and 17, the cytogenetic results reveal that other chromosomes also may be nonrandomly gained as part of multiple polysomies in breast carcinomas. In addition, the tumors with multiple polysomies were generally of high histologic grade and with metastasis to axillary lymph nodes, suggesting that multiple wholechromosome gains may be a pathway of genetic evolution or progression or both in some breast carcinomas.

Adult↗
PubMed1999

Chromosomal aberrations in breast cancer: a comparison between cytogenetics and comparative genomic hybridization.

The analysis of chromosomal imbalances in solid tumors using comparative genetic hybridization (CGH) has gained much attention. A survey of the literature suggests that CGH is more sensitive in detecting copy number aberrations than is karyotyping, although careful comparisons between CGH and cytogenetics have not been performed. Here, we compared cytogenetics and CGH in 29 invasive breast cancers after converting the karyotypes into net copy number gains and losses. We found 15 tumors (56%) with a significant agreement between the two methods and 12 tumors (44%) where the methods were in disagreement (two cases failed CGH analysis). Interestingly, in 13 of the 15 tumors where the two methods were concordant, there was also a strong correlation between chromosome index and DNA index by flow cytometry. In the opposite situation, i.e., when chromosome and DNA indices were not matching, there was disagreement between cytogenetics and CGH in 10 of the 12 tumors. Of the discordant cases, all except one had a "simple" abnormal karyotype. Unresolved chromosomal aberrations (marker chromosomes, homogeneously staining regions, double minutes) could not completely explain the differences between CGH and karyotyping. A likely explanation for the discrepancies is that the methods analyzed different cell populations. Gains and losses found by CGH represented the predominant (often aneuploid) clone, whereas the abnormal, near-diploid karyotypes represented minor cell clone(s), which, for unknown reasons, had a growth advantage in vitro.

Aneuploidy↗
PubMed1999

Analysis of 35 cases of localized and diffuse tenosynovial giant cell tumor: a report from the Chromosomes and Morphology (CHAMP) study group.

The karyotypes of 44 specimens from 35 patients with localized (n = 19) or diffuse (n = 16) tenosynovial giant cell tumors were studied. The majority of cases in both categories (11 of 19 localized; 12 of 16 diffuse) displayed clonal chromosomal aberrations, with a complex karyotype in three cases and a simple chromosomal aberration in the others. No difference in the distribution of karyotypic abnormalities was found between the localized and diffuse form except for trisomies (usually of chromosomes 5 and/or 7), which were more frequent in the diffuse type. The short arm of chromosome 1 (1p11-13) was most frequently rearranged, with 7 of 11 localized and 7 of 12 diffuse lesions affected. These findings indicate that the localized and diffuse forms of tenosynovial giant cell tumor might represent two morphologic manifestations of the same entity. The high frequency of clonal chromosomal abnormalities, with a clustering of structural rearrangements to 1p11-13, suggests that this disease is most likely neoplastic in nature and paves the way to search for gene(s) that might be involved in its development.

Adolescent↗
PubMed1999

Abnormal cell cycle regulation in malignancy.

The cell cycle consists of an initial growth phase (G1), DNA replication (S), a gap phase (G2), and mitosis (M), after which the cell may differentiate or enter the resting state (G0). The cycle is driven by a number of positive and negative regulatory phosphorylation and dephosphorylation events, involving protein kinases, protein phosphatases, cyclins, cyclin-dependent kinases, and cyclin-dependent kinase inhibitors, that ultimately impinge on the activity of transcription factors. Unreplicated or damaged DNA blocks the progression of the cell cycle at checkpoints, including a late G1 checkpoint regulated by the dephosphorylated retinoblastoma protein and a late G2 checkpoint regulated by the phosphorylation of cyclin-dependent kinase 1 complexed with cyclin B. Many cell cycle regulator genes may be considered proto-oncogenes or tumor suppressor genes, and point mutations, amplifications, deletions, or rearrangements involving their loci, particularly those in the "RB pathway," are associated with various tumors. A number of molecular techniques may be used to detect genomic alterations or posttranscriptional modifications, but immunohistochemistry remains the most common method to determine expression levels of a regulatory protein. Multivariate analysis of the usefulness in prognosis has been applied most often for the general proliferation antigen Ki-67.

Biomarkers, Tumor↗
PubMed1998

Cytogenetic and fluorescence in situ hybridization characterization of chromosome 1 rearrangements in head and neck carcinomas delineate a target region for deletions within 1p11-1p13.

Cytogenetic analyses have revealed structural rearrangements of chromosome 1 in a large fraction of head and neck carcinomas (HNCA). These aberrations frequently affect chromosomal band 1p13 and the centromeric region, the latter often in the form of isochromosome i(1q) and whole-arm translocations. To delineate the critical region involved in rearrangements of proximal 1p, we have undertaken a more precise breakpoint mapping in 13 HNCAs, using metaphase fluorescence in situ hybridization with 11 yeast artificial chromosome (YAC) clones spanning 1p. All of the tumors had chromosome 1 changes at G-banding analyses. Fluorescence in situ hybridization showed that in almost all of the cases, at least one copy of chromosome 1 was affected by centromeric rearrangement. By the use of YAC clones mapped to juxtacentromeric regions and a centromere-specific alpha-satellite probe, we detected variable breakpoints in the whole-arm translocations. At the cytogenetic level, 1p13 rearrangements were frequent. However, molecular breakpoints within this band varied among the HNCAs tested. The lack of consistently rearranged chromosome segments indicates that the pathogenetically important consequence of 1p rearrangements in HNCAs is loss and/or gain of genes outside the breakpoint regions. In an assessment of the genomic imbalances, partial or complete overrepresentation of 1q was seen in eight cases. Loss of 1p material was also identified in eight cases; and in four of them, the deleted segments were too small to be discovered by G-banding analysis. The minimal overlapping deleted region was in the interval between YAC 959C4 (band p11-p12) and the centromere (p10). Our findings indicate that a target region potentially harboring tumor suppressor gene(s) crucial for HNCA is located within chromosomal bands 1p11-p13.

Centromere↗
PubMed1998

A case of dermatofibrosarcoma protuberans with a ring chromosome 5 and a rearranged chromosome 22 containing amplified COL1A1 and PDGFB sequences.

Dermatofibrosarcoma protuberans (DFSP) is a cutaneous tumour of borderline malignancy, the cytogenetic features of which include the translocation t(17;22)(q22;q13) or, more commonly, supernumerary ring chromosomes containing material from 17q22 and 22q13. These rearrangements result in the COL1A1/PDGFB fusion gene. Here, we describe a case of DFSP displaying a ring chromosome 5 together with a large marker chromosome composed of chromosome 22 alphoid DNA, material from distal 12q and amplified COL1A1 and PDGFB sequences. This is the first case of DFSP with multiple copies of COL1A1 and PDGFB not confined to ring chromosomes, showing that DFSP is similar to other borderline malignant mesenchymal tumours, where rings and giant markers are alternative vehicles for amplified material.

Adolescent↗
PubMed1998

Cytogenetic findings in invasive breast carcinomas with prognostically favourable histology: a less complex karyotypic pattern?

Seventeen invasive primary breast carcinomas of histological types usually considered to be prognostically favourable (2 medullary, 3 papillary, 3 tubular, and 9 mucinous carcinomas) were analysed as part of an ongoing study of the cytogenetics of breast cancer. Thirteen of the tumours (7 mucinous, 2 medullary, 2 papillary, and 2 tubular carcinomas) showed clonal chromosome aberrations. Trisomy 7 and i(1q) were present as sole and recurrent aberrations in the mucinous tumours. The 2 tubular carcinomas and I papillary carcinoma had simple numerical changes only, whereas the second papillary tumour had a balanced translocation as the sole anomaly. Both medullary carcinomas had chromosome numbers in the triploid range, with clones displaying structural and numerical changes. Our data, especially when collated with information on previously published cases of mucinous, papillary, tubular, and medullary breast carcinomas, show that the former 3 histological types, in keeping with their recognised prognostic advantage, appear to exhibit relatively simple karyotypic changes, i.e., numerical aberrations, balanced translocations, and near-diploid chromosome numbers. Medullary carcinomas on the other hand, appear to have more complex karyotypes, similar to those described for the more common ductal and lobular subtypes of breast carcinoma.

Adenocarcinoma, Mucinous↗
PubMed1998

Characterization of a malignant eccrine poroma by cytogenetic and fluorescence in situ hybridization techniques.

We have cytogenetically and by fluorescence in situ hybridization (FISH) analyzed short-term cultures from a malignant eccrine poroma, a type of tumor in which chromosomal abnormalities have previously not been reported. Combining the results from G-banding and FISH, the karyotype was interpreted as 50,XX,t(3;11;12)(q21;p15;q15),+5,+7,+9, +9,t(12;22)(q13;q13),+del(12)(q15),der(15)t(3;15) (q23;p13),der(17)t(8;17)(q22;p13),-20,add(22)(q13).

Acrospiroma↗
PubMed1998

Comparison of chromosomal patterns with clinical features in 165 lipomas: a report of the CHAMP study group.

Soft tissue lipomatous tumors are morphologically heterogeneous. Various morphologic features are associated with specific chromosomal patterns and clinical features such as age, sex, and tumor site, location, and size. Simple lipomas are known to be karyotypically heterogeneous, but this has not been correlated with clinicopathological features. In 165 cases of solitary soft tissue lipoma, short-term cultures were analyzed cytogenetically. The karyotypes were divided into the following groups: normal karyotype; 12q13-15 aberrations; 6p rearrangements; 13q rearrangements, 8q11-13 aberrations; ring or giant marker chromosomes or both; other aberrations. The tumors were reexamined morphologically without knowledge of the karyotypic or clinical data. An abnormal chromosomal pattern was observed in 129 of 165 cases (78%): in 75 of 90 (83%) lipomas in the extremities and in 43 of 63 (68%) trunk wall lipomas. Chromosomal aberrations were present in 69 of 90 (77%) subcutaneous tumors and in 59 of 64 (80%) deep tumors. A normal karyotype was twice as frequent in tumors in patients under 30 years of age than in those from older individuals (6 of 16 vs. 30 of 149, 40% resp. 20%). Apart from the finding that normal karyotypes were more common in patients younger than 30 years, there was no significant association between cytogenetic pattern and patient sex or age or tumor localization, size, or depth. The pathogenetic basis and clinicopathologic relevance (if any) of the cytogenetic subtypes among benign lipomas remain unexplained.

Adolescent↗
PubMed1998

Trisomy 3 as the sole karyotypic change in a pediatric immature teratoma.

Cytogenetic analysis of short-term cultured cells from an immature ovarian teratoma of a 9-year-old girl disclosed an extra copy of chromosome 3 as the sole clonal abnormality. The fact that trisomy 3 was previously reported as the only karyotypic change in two ovarian germ-cell tumors--one teratoma NOS and one immature teratoma--suggests that gain of chromosome 3 constitutes an early and pathogenetically important change in a subset of female germ-cell tumors.

Child↗
PubMed1998

Unbalanced chromosomal rearrangements in a metastasizing salivary gland tumor with benign histology.

Benign metastasizing pleomorphic adenoma (BMPA) is a rare tumor of the salivary glands. Despite benign histopathologic features, it can metastasize and is sometimes lethal. No chromosomal data have been reported for this tumor type. We have by chromosome banding and fluorescence in situ hybridization analysis examined the short-term cultures of three skeletal metastases from a BMPA and identified two related hypodiploid clones: 44,XX,dic(3;22)(p11;q13) or der(3)t(3;22)(p11;q?) add(22)(q?),der(9;21)(q10;q10),der(13)t(1;13)(q11;p13)/45,XX,-3,der(9;21 ) (q10;q10),der(13)t(1;13)(q11; p13),?der(22)t(3;22)(q22;q13), +mar. The karyotypic features of this BMPA thus differ from the characteristic cytogenetic findings in pleomorphic adenomas and carcinomas ex pleomorphic adenoma.

Adenoma, Pleomorphic↗
PubMed1998

Cytogenetic analysis of four angiosarcomas from deep and superficial soft tissue.

Angiosarcomas are rare malignant vascular tumors, most commonly found in the skin or superficial soft tissue. We found clonal chromosome aberrations in four short-term cultured angiosarcomas. Two cases were diagnosed as epithelioid angiosarcomas, and one as postmastectomy angiosarcoma. Two of the tumors were deep-seated and two were superficial. Angiosarcomas from deep, soft tissue are extremely rare and have never been cytogenetically investigated before. The chromosome number ranged from hypodiploid to hypertriploid. When the results from the present study were combined with data on the four previously reported cytogenetically aberrant angiosarcomas, the most frequently rearranged chromosomes were 5, 7, 8, 13, 15, 20, 22, and the Y chromosome. Recurrent changes, each found in three of these eight angiosarcomas, were gains of 5pter-p11, 8p12-qter, and 20pter-q12, losses of 7pter-p15 and 22q13-qter, and -Y in two of three men.

Adult↗