Wendy L. Golden

Genetic and phenotypic changes associated with the acquisition of tumorigenicity in human bladder cancer.

There has been a general lack of human paired cell lines that both reproduce the in vivo spectrum of tumor progression of bladder cancer and have some of the genetic changes associated with progression in human tumor tissue. T24, a cell line established from an invasive human transitional cell carcinoma (TCC) of the bladder, has been used extensively in bladder cancer research. However, a significant limitation of this cell line is its lack of tumorigenicity when injected into immunocompromised mice. This characteristic was used to our advantage as we sought to characterize T24T, a highly tumorigenic variant that could then be used to elucidate the genes responsible for human bladder tumor progression. In culture, T24T has a faster doubling time, reaches a higher cell density in monolayer culture, and is more motile than T24 at higher cell densities. T24T is able to form colonies in soft agar, whereas T24 is not, and expresses HRAS, a gene associated with increased aggressiveness in human TCC, at higher levels than T24. Most importantly, T24T forms solid tumors when injected subcutaneously in SCID mice both with and without Matrigel (Sigma, St. Louis, MO), whereas T24 does not. Cytogenetically, the 2 cell lines contain at least 5 shared structural anomalies, as determined by detailed karyotyping. Interestingly, T24T has acquired 4 new structural changes, 3 of which [add(10)(p12), i(10)(q10), −15] have been observed in loss of heterozygosity (LOH) studies of tumor progression in human TCC. It appears that the T24/T24T model may be an excellent tool for the study of human TCC progression because of its relationship with known karyotypic changes associated with human bladder cancer progression. We are currently taking advantage of these paired cell lines to identify genes involved in human TCC progression. Genes Chromosomes Cancer 27:252–263, 2000.

Loss of chromosomes 22 and 14 in the malignant progression of meningiomas: A comparative study of fluorescence in situ hybridization (FISH) and standard cytogenetic analysis☆

The majority of meningiomas are classified as typical and have a relatively benign course. However, approximately 10% are diagnosed as atypical, anaplastic, or malignant and have a worse prognosis. The genetic differences between the typical and higher grade meningiomas are not well characterized, although there appear to be increasingly complex karyotypic changes associated with the higher grade tumors. Because higher grade meningiomas are not common tumors, and because of the inherent problems associated with the culturing of tumors, the use of interphase cytogenetic techniques with paraffin-embedded archival material is desirable for studying these neoplasms. To determine its accuracy in detecting aneuploidy, we performed fluorescence in situ hybridization (FISH) on 2-micron paraffin sections of nine previously karyotyped meningiomas using an alpha-satellite probe for chromosomes 14 and 22. Sections of normal tissue from six patients without malignancy were used as controls. FISH analysis detected all of the chromosome losses in the meningioma cases that had been characterized cytogenetically. In five cases, cell lines not detected by standard cytogenetics were identified by FISH. These results indicate that FISH is a reliable method for detecting chromosomal loss and may be more sensitive than standard cytogenetics alone. Furthermore, the results of this study support the concept that loss of chromosome 14 is associated with malignant progression in meningiomas.

Spermatid-Specific Expression of the Novel X-Linked Gene Product SPAN-X Localized to the Nucleus of Human Spermatozoa

Abstract Formation of mature spermatozoa involves a series of dramatic molecular and morphological changes in the male germ cell lineage. These changes result from the temporally regulated transcription and translation of several testis-specific gene products. Here, we describe a novel, testis-specific protein designated SPAN-X for sperm protein associated with the nucleus on the X chromosome. SPAN-X sequences showed no significant similarity with known cDNA or peptide sequences. The SPAN-X peptide sequences contained three overlapping consensus nuclear localization signals, a high percentage (33%–37%) of charged amino acid residues, and a relatively acidic isoelectric point (pI; 4.88–6.05). Northern analysis of mRNA from multiple human tissues identified a SPAN-X transcript exclusively in the testis. In situ hybridization of human testes sections showed SPAN-X mRNA expression in haploid, round, and elongating spermatids. The SPANX gene was mapped to chromosome Xq27.1 by fluorescence in situ hybridization and by Southern blot analysis of human/mouse somatic cell hybrids. On Western blots of human sperm proteins, antirecombinant SPAN-X antibodies reacted with broad bands migrating between 15–20 kDa. Immunofluorescent labeling of human spermatozoa demonstrated SPAN-X localization to nuclear craters and cytoplasmic droplets. Expression of SPAN-X, an X-linked gene product, exclusively in haploid spermatids leads to interesting questions regarding the transcription of sex-linked genes during spermiogenesis.

Chromosome 22q11.2 deletion in a boy with Opitz (G/BBB) syndrome

This report is on a 14-month-old boy with manifestations of Opitz (G/BBB) syndrome in whom a 22q11.2 deletion was found. Deletion analysis was requested because of some findings in this patient reminiscent of velocardiofacial (VCF) syndrome. The extent of aspiration and of respiratory symptoms in this child is not usually seen in VCF syndrome. Opitz syndrome maps to at least two loci, one on Xp, the other on 22q11.2.

Multiple areas of intestinal atresia associated with immunodeficiency and posttransfusion graft-versus-host disease

We describe an infant with multiple segmental areas of atresia of the small and large bowel, with histologic features characteristic of the hereditary form of the disease. Posttransfusion graft-versus-host disease developed first, and then immunodeficiency was found. This report confirms the association between hereditary multiple intestinal atresia and immunodeficiency. We recommend irradiation of blood products in patients with multiple intestinal atresia pending evaluation of immune system status.

Development and characterization of xenograft model systems for adenoid cystic carcinoma.

Adenoid cystic carcinoma (ACC) is one of the most common malignancies to arise in human salivary glands, and it also arises in the glandular tissue of other organ systems. To address the paucity of experimental model systems for this tumor type, we have undertaken a program of transplanting tissue samples of human ACC into immunodeficient nu/nu mice to create xenograft model systems. In 17 of 23 attempts (74%), xenograft tumors were successfully grown. In all cases, the histologic appearance of the donating tumor was recapitulated in the subsequent xenograft. Characterization of a subset of xenograft models by immunohistochemical biomarkers and by RNA transcript microarray analysis showed good fidelity in the recapitulation of gene expression patterns in the xenograft tumors compared with the human donor tumors. As ACC is known to frequently contain a t(6;9) translocation that fuses the MYB and NFIB genes, fluorescence in situ hybridization (FISH) of 12 ACC xenograft models was performed that assayed MYB locus break-apart and MYB–NFIB locus fusion. Of 12 xenograft models, 11 (92%) revealed MYB locus rearrangement and 10 (83%) showed evidence of fusion of the MYB and NFIB loci. The two related xenograft models (derived from primary and metastatic tumors, respectively, of the same human subject) were karyotyped, showing a t(1;6) translocation, suggesting MYB translocation to a novel fusion partner gene. Overall, our results indicate that ACC is amenable to xenografting and that ACC xenograft models recapitulate the molecular and morphologic characteristics of human tumors, suggesting utility as valid experimental and preclinical model systems for this disease.

Cardiac phenotypes in chromosome 4q− syndrome with and without a deletion of the dHAND gene

Purpose: Terminal deletions of chromosome 4q are commonly associated with cardiovascular malformations (CVMs). The dHAND gene (HAND2, heart and neural crest derivative express 2), a basic helix-loop-helix transcription factor expressed in the developing heart, maps to 4q33. A targeted deletion in mouse shows that dHAND plays an important role in heart development, suggesting that haploinsufficiency of dHAND in patients with 4q deletions may be causal for CVMs. The purpose of this study is to examine the possible association between dHAND haploinsufficiency with the CVMs that occur in patients with 4q terminal deletions.Methods: Fluorescence in situ hybridization (FISH) was performed with a human dHAND genomic probe on five patients with terminal deletion at 4q33 or 4q34.Results: Of the three patients with a deletion of the dHAND locus, two had CVM (both valvar pulmonic stenosis). Of the two patients without a deletion of the dHAND gene, one had a small atrial septal defect noted on autopsy. In one of the patients with breakpoint on chromosome 4 assigned to 4q34.2 by GTG-banding, FISH revealed deletion of the dHAND gene.Conclusion: The results suggest that cardiac phenotypes are very variable in patients with the terminal deletion of chromosome 4q and that haploinsufficiency of the dHAND is not necessarily associated with CVMs. The correct cytogenetic interpretation of terminal chromosome deletions might be augmented by FISH.

A Chimeric RNA Characteristic of Rhabdomyosarcoma in Normal Myogenesis Process

UNLABELLED Gene fusions and their chimeric products are common features of neoplasia. Given that many cancers arise by the dysregulated recapitulation of processes in normal development, we hypothesized that comparable chimeric gene products may exist in normal cells. Here, we show that a chimeric RNA, PAX3-FOXO1, identical to that found in alveolar rhabdomyosarcoma, is transiently present in cells undergoing differentiation from pluripotent cells into skeletal muscle. Unlike cells of rhabdomyosarcoma, these cells do not seem to harbor the t(2;13) chromosomal translocation. Importantly, both PAX3-FOXO1 RNA and protein could be detected in the samples of normal fetal muscle. Overexpression of the chimera led to continuous expression of MYOD and MYOG-two myogenic markers that are overexpressed in rhabdomyosarcoma cells. Our results are consistent with a developmental role of a specific chimeric RNA generated in normal cells without the corresponding chromosomal rearrangement at the DNA level seen in neoplastic cells presumably of the same lineage. SIGNIFICANCE A chimeric fusion RNA, PAX3-FOXO1, associated with alveolar rhabdomyosarcoma, is also present in normal non-cancer cells and tissues. Its transient expression nature and the absence of t(2;13) chromosomal translocation are consistent with a posttranscriptional mechanism. When constantly expressed, PAX3-FOXO1 interfered with the muscle differentiation process, which presumably contributes to tumorigenesis.

Cytogenetic Abnormalities in Primary Bronchopulmonary Leiomyosarcoma of Childhood

Primary bronchopulmonary leiomyosarcoma (PBLMS) is a rare malignant neoplasm in all age groups and only 10 pediatric cases of PBLMS have been reported. This report presents cytogenetic findings of a PBLMS from an 8-year-old boy. Tumor diagnosis was established by using routine histopathology, immunohistochemistry, and electron microscopy. The karyotype was highly complex, demonstrating consistent structural abnormalities of chromosomes 1, 5, 6, and 7, relative gain of chromosomes 2 and 11, and relative loss of chromosomes 9, 19, 20, and 22, along with the presence of multiple marker chromosomes. Cytogenetic results of previously reported leiomyosarcomas are reviewed and compared with the present case.

Marfan and cri du chat syndromes in an 18-month-old child: evidence of phenotype interaction

We report on an 18‐month‐old girl who has both the cri du chat and Marfan syndromes. She was born at term to a 29‐year‐old woman with the clinical diagnosis of Marfan syndrome. An evaluation for developmental delay at 2 months of age showed a karyotype of 46,XX,del(5)(15.1), consistent with cri du chat syndrome. At age 18 months she was tall (90 cm, >95th centile), with an decreased upper segment:lower segment ratio (1.0), and microcephalic (OFC 42.5 cm, <5th centile). Facial features were typical of cri du chat syndrome. The palm, middle finger and foot lengths were at or above the 95th centile for age. She was hypotonic, and her developmental level was approximately 8–10 months. Echocardiography showed redundant mitral valve tissue, mild mitral insufficiency, dilated aortic sinuses, and a small muscular VSD. We would have anticipated that a patient with an autosomal deletion who also had Marfan syndrome would have had growth failure. However, in this patient the skeletal features of Marfan syndrome (increased body length, decreased upper segment:lower segment ratio, and increased palm, finger, and foot length) predominate.