Fatal outcome in a female monozygotic twin with X-linked hypohydrotic ectodermal dysplasia (XLHED) due to a de novo t(X;9) translocation with probable disruption of the EDA gene.

UNLABELLED: Ectodermal dysplasias are a group of congenital disorders with defective development of the epidermis and its appendages. X-linked hypohydrotic ectodermal dysplasia (XLHED; OMIM 305100) is the most common form of ectodermal dysplasia. We report on two monozygotic twin girls with XLHED due to a t(X;9) translocation causing a disruption of the EDA gene and non random inactivation of the normal X chromosome. One of the girls died unexpectedly at 2.5 years of age. Autopsy revealed that lack of normal tracheobronchial secretions leading to complete tracheal obstruction by mucous debris was the probable cause of death. CONCLUSION: Morbidity and mortality of ectodermal dysplasias in infancy and early childhood can be significant. Early diagnosis by paediatricians is important and complications should be anticipated.

Molecular characterization of the deletion in retinoblastoma patients with 13q14 cytogenetic anomalies.

We investigated the molecular deletions of twelve patients presenting with retinoblastoma and a cytogenetic abnormality including band 13q14. Dinucleotide markers spanning the complete chromosome 13 as well as two intragenic markers were analyzed in patients and their two parents. The deletion was considered confirmed when one heterozygous allele was missing, potential when a homozygous allele was observed in continuity with a clearly deleted allele, and noninformative when a homozygous allele was observed adjacent to a nondeleted region. The patients could be classified into three groups based on their cytogenetic abnormalities. In group 1, the cytogenetic deletion was restricted to band13q14 with confirmed or potential molecular deletions extending from D13S328 to D13S153. Although a possible common centromeric deletion breakpoint could exist for three of the patients and a common telomeric deletion breakpoint for two, the cytogenetic deletion was different for most of them. Group 2 included patients with a cytogenetic deletion extending up to 13q22. At the molecular level, the telomeric breakpoints were between the RB1 gene and D13S156. Here again, it is quite unlikely that a common telomeric breakpoint was responsible for the deletion. Group 3 consisted of special cases with either a paracentric inversion or a complex translocation. The cytogenetic abnormalities around 13q14 correlate with the molecular deletions that were observed in this study. Associated malformations cannot be easily predicted from the size of the deletions.

Further delineation of the facial 13q14 deletion syndrome in 13 retinoblastoma patients.

Thirteen years ago, Motegi and colleagues (J Med Genet 1987;24:696-697) summarized the specific facial phenotype of six Japanese retinoblastoma patients with interstitial 13q14 deletions. Among a series of 228 propositi with retinoblastoma referred to the Lausanne Retinoblastoma Clinic for treatment and genetic counseling between 1986 and 1997, 13 (5.7%) were diagnosed with a cytogenetic de-novo 13q14 deletion. We confirm the presence of the reported facial phenotype in our population of Caucasian patients and describe additional clinical traits, thus extending the facial phenotype associated with the 13q14 deletion. Del(13q14) comprises, among others, cranial anomalies, frontal bossing, deeply grooved and long philtrum, depressed and broad nasal bridge, bulbous tip of the nose, thick lower lip, thin upper lip, broad cheeks, and large ears and lobules. Recognition of this particular facial appearance was instrumental in the genetic diagnosis of 13q deletions and in the presymptomatic diagnosis of retinoblastoma in a significant number of our cases. Identification of this phenotype in a retinoblastoma patient allows for efficient diagnosis of recurrence in his progeny and/or sibship, while its ignorance will compromise genetic counseling due to the possible difficulties in detecting large deletions by standard molecular mutation analysis. Recognition of this syndrome in newborns without known familial risk for retinoblastoma is even more important as it is a clear warning sign that indicates immediate ophthalmic examination.

[Quick prenatal diagnosis using FISH in the analysis of non-cultured amniotic fluid cells]. / Recours au diagnostic prénatal rapide par l'analyse FISH des cellules du liquide amniotique non cultivées.

We report our experience with fluorescence in situ hybridization (FISH) on uncultured amniocytes and standard cytogenetic analysis. The method have been suggested to 259 patients and performed for 199 amniotic fluid samples. Commercially available chromosome-specific DNA probes (Aneurysm) for chromosomes 13, 18, 21, X and Y were used. All full trisomy 18, 21 and monosomy X were detected by FISH analysis with exception of one case of mosaic monosomy X. No false-positive result was observed. The efficiency, practicability and acceptability of the FISH diagnosis are discussed.

Malignant progression of SV40-immortalised human milk epithelial cells.

A human breast epithelial cell line (Hu-MI), established by microinjecting SV40 DNA into human milk epithelial cells, exhibits the phenotype of luminal epithelial cells and is neither clonogenic nor tumorigenic. From this cell line we have selected two sublines, HuMI-T and HuMI-TTul, reflecting different stages of spontaneous transformation. HuMI-T cells grow anchorage-independently, but do not induce tumours in nude mice. HuMI-TTul cells are clonogenic as well as tumorigenic. Cells from both lines exhibit polymorphic structural and numerical chromosome aberrations. Immortalisation of normal luminal epithelial cells from human mammary gland with SV40 DNA alone may thus cause random genetic changes eventually resulting in tumorigenic cell lines. Since Hu-MI, HuMI-T and HuMI-TTul represent some of the consecutive stages taking place during cellular transformation, they are particularly suited as a novel in vitro model system to study progression of human breast cancer.

Responsiveness of three newly established human colorectal cancer cell lines to transforming growth factors beta 1 and beta 2.

We have established 3 new human colorectal cancer cell lines (LS411N, LS513, and LS1034) from clinical biopsy samples. These lines are tumorigenic and grow s.c. as adenocarcinomas in nude mouse xenografts. Specific marker chromosomes are observed in each line. Carcinoembryonic antigen is expressed at the surface of all 3 lines, but with marked quantitative differences. Indeed, less than 10% of the cells from the HT-29 line used as a reference express carcinoembryonic antigen while more than 90% of the LS1034 cells do so. LS513 and LS1034 consistently express HLA class I antigens and intercellular adhesion molecule 1 which are not detected at the surface of the LS411N cells. No expression of HLA class II antigens DR, DQ, and DP has been measured on any of the lines. All three lines grow well in 5% fetal calf serum medium without addition of exogenous growth factors. The LS1034 line has been adapted to growth in serum-free conditions and exhibits increased clonogenicity when cells are seeded in serum-free methylcellulose medium, as compared with medium containing 5% fetal calf serum. The LS513 and LS1034 lines have proved to be of particular interest since they respond to the growth-inhibitory action of TGF-beta 1 and TGF-beta 2 in both liquid and semisolid medium. Both factors were, at pM concentrations, equipotent inhibitors of LS1034 cell proliferation. In contrast, higher concentrations of TGF-beta 1 are inhibitory for proliferation of LS513 cells, whereas TGF-beta 2 has no effect on the growth of these cells in liquid assay. On this basis, using appropriate anti-TGF-beta 1 and anti-TGF-beta 1 IgY, we developed a bioassay for TGF-beta 1 and TGF-beta 2. Two of the three lines have indeed been shown to produce latent-TGF-beta 1 activity.

[Lausanne study of retinoblastoma, 1986-90: deletion of esterase D locus in a collective of 128 patients]. / Consultation Lausannoise du rétinoblastome, 1986-1990: déletions au locus de l'estérase D dans un collectif de 128 patients.

Activity and phenotype of red blood cell esterase D were systematically determined in a population of 128 retinoblastoma patients from 99 families and compared to 158 controls, in order to detect a chromosome 13q14 deletion. Among these patients 12 were healthy carriers and 116 affected carriers of a mutant allele of the retinoblastoma susceptibility gene (110 retinoblastoma, 5 retinoma, 1 phtisis bulbi). 4 patients were found to have decreased ESD levels in connection with 13q14 deletion which was confirmed by chromosome analysis. The data presented here suggest that ESD quantification has a high specificity and sensitivity for the detection of homogenous chromosome 13 deletions in retinoblastoma patients.

Epidermal growth factor responsiveness of a new human neuroblastoma cell line.

A human neuroblastoma cell line, CA-2E, has been established from a bone-marrow aspirate of a 16-month-old boy with progressive disease. The karyotype and antigen phenotype of the cells correspond to those of a neuroblastoma. This cell line grows well in liquid cultures supplemented with 5% fetal calf serum; conversely, colony formation in semi-solid medium by cells from early passages is dependent upon exogenous EGF. With time in continuous culture, the cloning efficiency in the absence of EGF increases, but the line remains sensitive to EGF, as evidenced by an enhancement of the number and size of colonies. A relative dependence upon EGF in liquid cultures has also been clearly demonstrated by limiting the concentration of serum. Long-term (over 2 weeks) treatment with EGF results in a decreased rate of proliferation, a decreased proportion of clonogenic cells, and the appearance of flat, epithelial-type cells. In some experiments, EGF also has a remarkable effect in inducing neurite outgrowth and process branching. Our results suggest that EGF may have both proliferation- and differentiation-inducing effects on this neuroblastoma cell line. We have also shown that EGF induces increased proliferation in 7 out of 8 other human neuroblastoma cell lines. Functional response of neuroblastoma cells to EGF appears to be a general phenomenon which may be related to a block in the normal maturation pathway of the neural crest cells from which this tumor originates.

Cytogenetic analysis of 570 first trimester chorionic villi samplings: technique and results.

In this report we present our experience based on 570 chorionic villi samplings performed by the transcervical method at 8 to 12 weeks gestation. Cytogenetic results were obtained for 551 samples, hence a failure rate of 3.33%. The previously described technique was modified by prolonging the incubation period to 48 hours. The total number of abnormalities was 26, which represents 4.71% of our sample. Of 24 chromosomal abnormalities, 21 were unbalanced and 3 were balanced of parental origin. Five discordant cases are thoroughly discussed.

Characterization of four human malignant glioma cell lines.

In this paper, the characterization of four human malignant glioma cell lines is described. The four lines are positive for glial fibrillary acidic protein (GFAP) in variable amounts. One of them, LN 992, is positive for S-100 protein. Myelin basic protein could not be detected in any of the four lines. The four lines had high levels of CNPase activity. The karyotype shows polyploidy for all lines, with modal numbers ranging from 80 to 120 and various numbers of marker chromosomes. Particular attention has been paid to the surface phenotype and a panel of three antiglioma monoclonal antibodies (Mabs), five antimelanoma Mabs, one anti-CALLA Mab, and two anti-HLA-DR Mabs has been used in an antibody-binding radioimmunoassay for the four cell lines. Lines LN 215 and LN 235 are positive with two antiglioma Mabs, LN 992 is negative. The four lines are positive with all five antimelanoma Mabs, except for LN 992 which ist negative with Mab D5. LN 992 and LN 215 are positive with the anti-CALLA Mab N2A12. LN 308 and LN 992 are positive with anti-HLA-DR Mab D4-22. There was no correlation between the in vitro morphology of the lines and the expression of the various biochemical or surface markers. These results stress the heterogeneity of the phenotype of human malignant glioma lines. These lines will be useful tools for further immunologic studies.