Frequent fusion of the JAZF1 and JJAZ1 genes in endometrial stromal tumors.

Endometrial stromal tumors are divided into three types: benign stromal nodules, endometrial stromal sarcomas, and undifferentiated endometrial sarcomas. A variety of cytogenetic abnormalities involving chromosome 7 have been reported in endometrial stromal sarcomas, including a recurrent t(7;17)(p15;q21). We have identified two zinc finger genes, which we have termed JAZF1 and JJAZ1, at the sites of the 7p15 and 17q21 breakpoints. Analyses of tumor RNA indicate that a JAZF1/JJAZ1 fusion is present in all types of endometrial stromal tumors; however, the fusion appears to be rarer among endometrial stromal sarcomas that would be considered high-grade according to certain classification schemes. These findings suggest that the less malignant endometrial stromal tumors may evolve toward more malignant types, but that some endometrial stromal sarcomas with relatively abundant mitotic activity may compose a biologically distinct group.

The der(17)t(X;17)(p11;q25) of human alveolar soft part sarcoma fuses the TFE3 transcription factor gene to ASPL, a novel gene at 17q25.

Alveolar soft part sarcoma (ASPS) is an unusual tumor with highly characteristic histopathology and ultrastructure, controversial histogenesis, and enigmatic clinical behavior. Recent cytogenetic studies have identified a recurrent der(17) due to a non-reciprocal t(X;17)(p11.2;q25) in this sarcoma. To define the interval containing the Xp11.2 break, we first performed FISH on ASPS cases using YAC probes for OATL1 (Xp11.23) and OATL2 (Xp11.21), and cosmid probes from the intervening genomic region. This localized the breakpoint to a 160 kb interval. The prime candidate within this previously fully sequenced region was TFE3, a transcription factor gene known to be fused to translocation partners on 1 and X in some papillary renal cell carcinomas. Southern blotting using a TFE3 genomic probe identified non-germline bands in several ASPS cases, consistent with rearrangement and possible fusion of TFE3 with a gene on 17q25. Amplification of the 5' portion of cDNAs containing the 3' portion of TFE3 in two different ASPS cases identified a novel sequence, designated ASPL, fused in-frame to TFE3 exon 4 (type 1 fusion) or exon 3 (type 2 fusion). Reverse transcriptase PCR using a forward primer from ASPL and a TFE3 exon 4 reverse primer detected an ASPL-TFE3 fusion transcript in all ASPS cases (12/12: 9 type 1, 3 type 2), establishing the utility of this assay in the diagnosis of ASPS. Using appropriate primers, the reciprocal fusion transcript, TFE3-ASPL, was detected in only one of 12 cases, consistent with the non-reciprocal nature of the translocation in most cases, and supporting ASPL-TFE3 as its oncogenically significant fusion product. ASPL maps to chromosome 17, is ubiquitously expressed, and matches numerous ESTs (Unigene cluster Hs.84128) but no named genes. The ASPL cDNA open reading frame encodes a predicted protein of 476 amino acids that contains within its carboxy-terminal portion of a UBX-like domain that shows significant similarity to predicted proteins of unknown function in several model organisms. The ASPL-TFE3 fusion replaces the N-terminal portion of TFE3 by the fused ASPL sequences, while retaining the TFE3 DNA-binding domain, implicating transcriptional deregulation in the pathogenesis of this tumor, consistent with the biology of several other translocation-associated sarcomas. Oncogene (2001) 20, 48 - 57.

Physical appearance and voice in male-to-female transsexuals.

It has been suggested that sex judgments of male-to-female transsexuals based on the voice may be influenced by the physical appearance of the clients. To explore this hypothesis, a listener experiment was designed in which a panel of 22 laypersons and 22 students in speech-language pathology rated the "femaleness" of fourteen male-to-female transsexuals from video-recorded speech samples in three modes of presentation: auditory-only presentation, visual-only presentation, and audiovisual presentation. Results indicate that appearance and voice are indeed interacting factors. Ratings from the auditory-only presentation were significantly lower than ratings from the audiovisual presentation and ratings from the visual-only presentation were significantly higher than those from the audiovisual presentation. It follows that the success of voice training in male-to-female transsexuals is not solely dependent on vocal characteristics and that speech pathologists should consider incorporating physical appearance as a treatment and outcome variable in the voice training of male-to-female transsexuals.

Cytogenetic-morphologic correlations in aneurysmal bone cyst, giant cell tumor of bone and combined lesions. A report from the CHAMP study group.

Aneurysmal bone cyst and giant cell tumor of bone are relatively rare bone tumors that sometimes coexist. We examined the karyotypes of 3 aneurysmal bone cysts, 12 giant cell tumors, and 3 combined lesions. All aneurysmal bone cysts showed involvement of chromosome segments 17p11-13 and/or 16q22. In addition, in 1 of the 3 giant cell tumors with secondary aneurysmal bone cyst, both chromosome bands were rearranged as well, albeit not in a balanced translocation. Seven out of 12 giant cell tumors were characterized by telomeric associations. One giant cell tumor showed a dup(16)(q13q22), suggesting the presence of a (minor) secondary aneurysmal bone cyst component, despite the absence of histological proof. Our results, combined with literature data further substantiate that segments 16q22 and 17p11-13 are nonrandomly involved in at least some aneurysmal bone cysts, irrespective of subtype (primary, secondary, intra/extraosseous, solid or classic). These findings strongly suggest that some aneurysmal bone cysts are true neoplasms. In addition, telomeric associations are the most frequent chromosomal aberrations in giant cell tumor of bone, the significance of which remains elusive. In combined giant cell tumor/aneurysmal bone cyst each component seems to retain its own karyotypic abnormality.

Recurrent chromosome aberrations in fibrous dysplasia of the bone: a report of the CHAMP study group. CHromosomes And MorPhology.

The nosologic status of fibrous dysplasia (FD), a well-known and relatively common bone lesion, is controversial. Information collected by the CHromosomes And MorPhology (CHAMP) study group on published and unpublished cases of fibrous dysplasia shows the presence of clonal chromosome changes in at least a proportion of these lesions. The chromosome aberrations found in FD lesions have been quite variable and have included both structural and numerical changes. Two of the three cases investigated at the study group had trisomy 2 as the sole acquired anomaly. Combined with previously published data, +2 and rearrangements involving chromosome band 12p13 have each been detected in 3 of 8 cases with abnormal karyotype of 11 in which chromosomal analysis has been performed, suggesting that FD is a neoplastic lesion rather than a "dysplastic" process, as has been generally believed and as implied by its very name.

Cytogenetic, clinical, and morphologic correlations in 78 cases of fibromatosis: a report from the CHAMP Study Group. CHromosomes And Morphology.

Whether fibromatoses are neoplastic or reactive lesions has long been controversial and the relationship, if any, between the superficial and deep forms (desmoid tumors) are poorly understood. Clinical, pathologic, and cytogenetic data of 78 cases of fibromatosis were analyzed and correlated with each other. The results demonstrate that clonal chromosome aberrations are a common feature of this entity, being present in 46% of desmoid tumors, although less frequent in the superficial types (10%). In the deep-seated extra-abdominal fibromatoses, trisomies 8 and 20 and loss of 5q material were the only recurrent features. No correlation between +8 and local recurrence was found. Our findings provide additional evidence for the neoplastic nature of fibromatoses.

Cytogenetic evidence of clonality in cutaneous benign fibrous histiocytomas: a report of the CHAMP study group.

AIMS: Cutaneous benign fibrohistiocytic tumours are among the most common soft tissue lesions. Their biological nature, in particular whether they are neoplastic or reactive, has long been disputed. Some morphological subtypes can be confused with sarcoma. Since available karyotypic data in these lesions are scarce, this study was undertaken to determine whether their cytogenetic analysis might demonstrate clonality and might help in differential diagnosis. METHODS AND RESULTS: Thirteen karyotyped benign cutaneous fibrous histiocytomas (BFH) were morphologically reassessed and classified as ordinary BFH (eight cases), cellular BFH (four cases), and one ankle-type lesion. Five cases (38%) showed clonal cytogenetic changes, although the aberrations varied and did not correlate with histological subtypes. Karyotypic aberrations were more common in cellular BFH (3/4) than in the ordinary BFH (2/8). CONCLUSIONS: The demonstration of clonal chromosome abnormalities, in at least some cases, supports the neoplastic nature of cutaneous BFH. The karyotypic changes identified are different from those in dermatofibrosarcoma, with which cellular BFH is often confused histologically.

Myofibroblastoma of the breast: genetic link with spindle cell lipoma.

Mammary myofibroblastoma is a rare tumour, mainly occurring in male patients. This paper describes two cases of mammary myofibroblastoma, with typical histological features, including the presence of fat cells and mast cells. Immunohistochemically, the spindle cells stained positively for desmin and CD34. Cytogenetically, both tumours showed partial monosomy 13q and in case 1, there was, in addition, partial monosomy 16q. Rearrangements affecting 13q and 16q occur typically in spindle cell lipomas. In addition to histological similarities, the hitherto unreported chromosomal changes in mammary myofibroblastoma, which are similar to the chromosomal aberrations in spindle cell lipoma, strongly suggest a link between these two tumours and are not in favour of myofibroblastoma being a primary solitary fibrous tumour of the breast.

Analysis of the P53, RB/D13S25, and P16 tumor suppressor genes in marginal zone B-cell lymphoma: An interphase fluorescence in situ hybridization study.

The genetic mechanisms underlying the genesis, disease progression, and high-grade transformation of marginal zone B-cell lymphoma (MZBCL) are poorly understood. We analyzed 33 cases of histologically and immunophenotypically well-characterized MZBCL (12 extranodal, 11 nodal, and 10 splenic MZBCL; 27 at primary diagnosis and six during the course of disease) by dual-color interphase fluorescence in situ hybridization (FISH) for deletions of tumor suppressor genes. We investigated loci known to play a role in the genesis or disease progression of other subtypes of lymphoid malignancies, namely the P53 gene (17p13), the retinoblastoma gene (RB, 13q14), the D13S25 locus (13q14), and the P16(INK4A) gene (9p21). Heterozygous deletions of P53 were detected in three out of the 33 cases, including two splenic and one extranodal MZBCL. One of these patients was analyzed at primary diagnosis and two during the course of disease. Heterozygous deletions of the RB gene (nodal MZBCL) and D13S25 (splenic MZBCL) were found in one case each. P16 deletions were not detected in any of our cases. We conclude that deletions of the analyzed tumor suppressor genes are relatively rare in MZBCL, which contrasts with the findings in some other subtypes of NHL.

Genetic abnormalities in marginal zone B-cell lymphoma.

Marginal zone B-cell lymphoma (MZBCL) including extranodal mucosa-associated lymphoid tissue (MALT)-type lymphoma, nodal, and splenic MZBCL represents a distinct subtype of B-non-Hodgkin's lymphoma. Recently, important progress in the elucidation of the genetic mechanisms underlying the pathogenesis and disease progression of these lymphomas has been made. The API2 gene, an inhibitor of apoptosis, and the novel MLT gene have been found to be altered by the t(11;18)(q21;21), which represents the most frequent structural chromosomal abnormality in extranodal low-grade MALT lymphoma. Another gene involved in the regulation of apoptosis, the BCL10 gene, has been cloned from a MALT lymphoma cytogenetically characterized by the t(1;14)(p22;q32). Along the same lines, inactivating mutations of the proapoptotic FAS gene have been detected in a relatively high proportion of extranodal MZBCLs. Considering these data and the fact that at least some MALT lymphomas show low levels of apoptosis and seem to escape from FAS-mediated apoptosis one may speculate that abrogation of apoptosis constitutes a central pathogenetic mechanism in the development of these lymphomas. The pathogenetic role of trisomy 3, the most frequent numerical chromosomal change of MZBCL, is not known. The minimal overrepresented region has been delineated to 3q21-23 and 3q25-29 using comparative genomic hybridization. The BCL6 proto-oncogene, located on 3q27, which is rearranged in some MZBCL and a high proportion of large cell B-cell lymphomas with extranodal localization, represents one of the candidate genes residing in these critical regions.

HMGI-C and HMGI(Y) immunoreactivity correlates with cytogenetic abnormalities in lipomas, pulmonary chondroid hamartomas, endometrial polyps, and uterine leiomyomas and is compatible with rearrangement of the HMGI-C and HMGI(Y) genes.

High-mobility group (HMG) proteins are nonhistone nuclear proteins that play an important role in the regulation of chromatin structure and function. HMGI-C and HMGI(Y) are members of the HMGI family of HMG proteins, and their expression in adult tissues generally correlates with malignant tumor phenotypes. However, HMGI-C and HMGI(Y) dysregulation as a result of specific rearrangements involving 12q15 and 6p21, the respective chromosomal sites in which the HMGI-C and HMGI(Y) genes are located, is also identified in a variety of common benign mesenchymal tumors, such as lipomas and uterine leiomyomata. The general prevalence of HMGI-C and HMGI(Y) protein expression and its correlation with chromosomal alterations in these benign tumors are unknown. We analyzed 95 human tumors (20 lipomas, 21 pulmonary chondroid hamartomas, 26 uterine leiomyomata, and 28 endometrial polyps) representing a selection of the benign lesions in which karyotypic alterations involving the chromosomal regions 12q15 and 6p21 are frequently detected. All cases were successfully karyotyped and some of them analyzed by fluorescent in situ hybridization with probes spanning the HMGI-C and HMGI(Y) genes. The results of this study demonstrate that expression of HMGI-C or HMGI(Y) is a common occurrence in lipomas, pulmonary chondroid hamartomas, leiomyomata, and endometrial polyps; that it correlates with 12q15 and 6p21 chromosomal alterations (p < 0.001); and that it is compatible with rearrangement of the HMGI-C and HMGI(Y) genes. The expression pattern and cellular localization of the immunoreactivity support the view that in biphasic lesions composed of a mixture of both stromal and epithelial cells, such as pulmonary chondroid hamartoma and endometrial polyps, the mesenchymal component is the site of the HMGI genetic alterations.

Peripheral primitive neuroectodermal tumour of the cervix.

Peripheral primitive neuro-ectodermal tumours (PNET) of the cervix are very rare. Here, we report the clinical, pathological, immunohistochemical and genetic features of a case of a PNET located in the cervix. Hysterectomy revealed a cervical tumour. On microscopic examination, a vaguely lobular arrangement of uniformly appearing neoplastic cells, with round to oval nuclei, distinct nuclear membranes and a clear, moderately glycogen-rich cytoplasm was seen. Cells stained positive for LEU 7, S 100, monoclonal NSE and particularly for MIC2. Neurogenic differentiation was also seen by electron microscopic examination. The genetic hallmark of PNET, a 22q12 rearrangement was demonstrated by fluorescence in situ hybridisation experiments, supporting the diagnosis. Awareness of the existence of primary PNET of the cervix is important to avoid confusion with other tumours of the cervix.

Involvement of chromosomes 1 and 18 in renal cell tumors.

A previously undescribed combination of cytogenetic abnormalities was detected in two renal cell tumors, one eosinophilic variant of the chromophilic type of renal cell carcinoma, and one oncocytoma. Both tumors shared loss of 1p material and monosomy 18. These complex changes, while being unusual, indicate that chromosome 1p rearrangements, rather than associated numerical changes, seem to play a crucial role in the development of renal tumors.

Comparative cytogenetic study of spindle cell and pleomorphic leiomyosarcomas of soft tissues: a report from the CHAMP Study Group.

Leiomyosarcomas (LMS) of soft tissues frequently show complex karyotypic changes, and no specific aberration has been identified. The aim of this study was to search for recurrent chromosome aberrations in soft tissue LMSs and to correlate these, if present, with morphological and clinical parameters. From a series of soft tissue sarcomas thoroughly reexamined cytogenetically and histopathologically, 45 LMSs were retrieved; 35 were classified microscopically as spindle cell, 3 as epithelioid, and 7 as pleomorphic. Clonal chromosome changes were present in 14, 3, and 3 cases, respectively. This series was combined with 11 previously published, karyotypically abnormal pleomorphic LMSs for cytogenetic-clinico-histopathological correlations. The breakpoints were widely scattered, with no predilection of any of the recurrent breakpoints and losses to any of the morphologic subtypes. Combining numerical and unbalanced structural changes, the most frequently lost segments were 3p21-p23 (11 cases), 8p21-pter, 13q12-q13, 13q32-qter (10 cases each), 1q42-qter, 2p15-pter, 18p11 (9 cases each), 1p36, 11q23-qter (8 cases each), and 10q23-qter (7 cases). The most frequent gain was 1q12-q31 (6 cases). There was a greater frequency of losses in 1p and 8p and a lower frequency of losses in 10q and 13q in tumors that had metastasized than in localized tumors. We conclude that LMSs with clonal abnormalities display highly complex karyotypic changes and extensive heterogeneity. No significant correlation exists between these changes and age and sex of the patients, or with depth of tumor, topography, microscopic subtype, or tumor grade. Losses in 1p36 and 8p21-pter may be associated with increased risk of metastases. Comparison of our findings in soft tissue LMS with those previously reported in LMS in other locations suggest that the karyotypic profile is more dependent on site of origin than on microscopic features.

Regional fine mapping of HMG17 to chromosomal band 1p35.

HMG17, a member of the high-mobility group of proteins, is ubiquitously expressed in higher eukaryotes. This protein has been shown to enhance transcriptional activity of many other genes. Recently, the HMG17 gene has been mapped to chromosomal band 1p36.1. Because this region is frequently involved in chromosomal aberrations of various human neoplasms, two PAC clones containing an HMG17 sequence were isolated. By fluorescence in situ hybridization (FISH) on prometaphase spreads, HMG17 was mapped to chromosomal band 1p35.

Cytogenetic characterization of peripheral nerve sheath tumours: a report of the CHAMP study group.

The findings of characteristic, sometimes pathognomonic, chromosome aberrations in several types of soft tissue tumours have not only added to our understanding of the mechanisms behind the genesis of these tumours, but have also revealed the importance of cytogenetic analysis as a diagnostic tool. For many soft tissue tumours, including peripheral nerve sheath tumours, the number of analysed cases is, however, still very low, precluding evaluations of the clinical or biological significance of different chromosomal patterns. As part of an ongoing project aiming at identifying clinical-histopathological-cytogenetic correlations among soft tissue tumours, a series of 46 benign, the vast majority of which were located in the extremities, and 20 malignant peripheral nerve sheath tumours (BPNSTs and MPNSTs, respectively) that had been successfully analysed by chromosome banding techniques were evaluated with regard to clinical, morphological, and cytogenetic features. Clonal chromosome aberrations were found in 20 BPNSTs, with abnormal karyotypes being significantly more frequent among Schwannomas than among neurofibromas. Recurrent aberrations, all of which were confined to the Schwannoma subtypes, included loss of 22q material, loss of a sex chromosome, and trisomy 7. The results show that the cytogenetic features of Schwannomas are not dependent on the site of origin. The MPNSTs, all of which had clonal chromosome aberrations, displayed complex karyotypes with numerous structural and numerical changes, except in two cases showing +7 and -22, respectively, as the sole changes. None of the recurrent imbalances was restricted to either NF1-associated or sporadic MPNST, nor was any of the imbalances significantly associated with clinical outcome. The presence of a triploid or tetraploid clone was, however, associated with grade 3 tumours and a poor prognosis. The cytogenetic findings in peripheral nerve sheath tumours show that the karyotype is a good discriminator between BPNSTs and MPNSTs, and that the pattern of aberrations among the latter may add prognostic information.

Cytogenetic investigation of transitional cell carcinomas of the upper urinary tract.

Cytogenetic investigation was attempted on 44 tumors from 44 patients with transitional cell carcinoma (TCC) of the upper urinary tract (pelvis and ureter), and karyotypes were obtained in 27 tumors. Numerical changes prevailed, but are not specific for this type of tumor (trisomy 7, -Y, or both). In the light of previously reported data on TCC, the finding of a del(9q) as the only anomaly in one of the cases may be meaningful. Patients showing -Y and/or trisomy 7 had a poor prognosis.