The involvement of the trans-generational effect in the high incidence of the hydatidiform mole in Africa.

INTRODUCTION: While the incidence of various chromosomal anomalies observed, including triploid partial moles is independent of the socio-economic level, higher incidences of complete hydatidiform mole "CHM" is generally associated with under developed areas. Moreover, studies have shown that some nutritional deficiencies are related to the abnormal development of oocytes and placenta. In Senegal and Morocco, the annual seasonal cycle contains one period with food shortages and the incidence of complete moles is significant. Accordingly, accurate statistical analyses have been performed in these two countries. METHODS: Each month during a one year period, we investigated the occurrence of normal conceptions, molar conceptions and the conception of the future patients in Senegal and Morocco. The comparisons of the conception dates for these three types of conception were analyzed using the Chi-squared test. RESULTS: 94% of the patients were conceived just prior to the period in the year with food shortages. Consequently, the development of the female embryos occurred under nutritional constraints, which negatively affect the recruitment of the vital factors required for the normal synthesis of DNA, proteins and placental differentiation. DISCUSSIONS: A nutritional deficiency in the mother at conception of their daughter (future patient) is implicated in the higher incidence of CHM in their daughters' filiation. These nutritional deficiencies during the first weeks of pregnancy will have repercussions on the normal development of the oocytes. Accordingly, these developmental impairments take place during the embryonic life of the future mothers of complete moles and not during the conception of the moles themselves.

[Partial hydatidiform mole in Morocco: an epidemiological and clinical study]. / Les môles hydatiformes partielles au Maroc: étude épidémiologique et clinique.

This retrospective study reviewed cases of partial hydatidiform mole (PHM) diagnosed at the University Hospital in Casablanca from 2000 to 2010 in order to examine the epidemiological, clinical, therapeutic and progressive pathological factors associated with PHM. All PHM cases confirmed clinically and sonographically at pathological examination were included. We identified 24 cases of PHM among 60 748 births and 1704 abortions, giving a frequency of 0.4 per 1000 pregnancies and 1.4% of abortions. The mean age was 26 years (range: 16-55 years). The circumstances of discovery and clinical ultrasound varied: 79.2% of patients sought consultation for bleeding; clinical thyrotoxicosis syndrome was found in 1 patient (4.2%). Physical examination showed increased uterine size in 83.3% of cases associated with a latero-uterine mass in 25%. The diagnosis was supported by an ultrasound examination combined with measurement of plasma betaHCG. Histological confirmation was made in all cases and treatment was endo-uterine aspiration. Neoplastic drift was observed in 1 case (4.2%) which went into remission with chemotherapy.

Partial hydatidiform mole in Morocco: an epidemiological and clinical study

This retrospective study reviewed cases of partial hydatidiform mole [PHM] diagnosed at the University Hospital in Casablanca from 2000 to 2010 in order to examine the epidemiological, clinical, therapeutic and progressive pathological factors associated with PHM. All PHM cases confirmed clinically and sonographically at pathological examination were included. We identified 24 cases of PHM among 60 748 births and 1704 abortions, giving a frequency of 0.4 per 1000 pregnancies and 1.4% of abortions. The mean age was 26 years [range: 16-55 years]. The circumstances of discovery and clinical ultrasound varied: 79.2% of patients sought consultation for bleeding; clinical thyrotoxicosis syndrome was found in 1 patient [4.2%]. Physical examination showed increased uterine size in 83.3% of cases associated with a latero-uterine mass in 25%. The diagnosis was supported by an ultrasound examination combined with measurement of plasma beta HCG. Histological confirmation was made in all cases and treatment was endo-uterine aspiration. Neoplastic drift was observed in 1 case [4.2%] which went into remission with chemotherapy

[Complete hydatiforme mole in Morocco: epidemiological and clinical study]. / Les môles hydatiformes complètes au Maroc : étude épidémiologique et clinique.

OBJECTIVE: Complete hydatidiform moles (CHM) are a real public health problem, especially in the "southern countries" and Asia, because of their impact on the female reproduction and the risk to progression to either invasive mole or choriocarcinoma. PATIENTS AND METHODS: We collected the cases of CHM referred to our department over a period of ten years (2000 to 2009). We will present our results, emphasize the modalities of diagnosis, treatment and evolution, with a review of literature. RESULTS: During this study, we identified 254 cases of CHM, and recorded 57,987 births and 1627 abortions. Their incidence was 0.43% of pregnancies. The mean age of our patients is 25 years old (16 to 55). Relative risk observed was much increased among women under 20 years old (×6.8) and those over 40 years old (×15). Both of nulliparous and primiparous patients represented 52.3% of the cohort. Eighty-five percent of patients belonged to an agricultural environment associated with a low socio-economic status. Uterine bleeding was the most common symptom accounting for 93.7%. Toxic syndrome was present in 18.5% of patients. Physical examination showed a highly increased uterine size in 85% of cases associated with lateral uterine mass in 25% of cases. The diagnosis was suspected using ultrasonography in all cases associated with an elevated level of plasmatic ß-human chorionic gonadotrophin (ßhCG). All cases were confirmed histologically. Treatment used was endo-uterine aspiration in all cases. Recurrence of CHM was documented in 25 patients or 9.4%. Neoplasic progression was observed for 6.3% of cases. All of them have evolved into remission with chemotherapy. DISCUSSION AND CONCLUSION: CHM continue to be a public health problem in Morocco, their incidence is among the highest ones. In fact, this studied population corresponds to the lowest socio-economic status and generally described as population at risk. It is subject to drastic weather's conditions causing loss of fresh products. Extreme ages and degree of parity are also risk factors described in the literature. Early diagnosis, appropriate treatment, and supervision of molar pregnancies are obligatory. Despite of the unfavourable initial conditions, our study shows that relevance and continuing care can significantly reduce the morbidity of moles.

High promoter hypermethylation frequency of p14/ARF in supratentorial PNET but not in medulloblastoma.

AIMS: Medulloblastoma (MB) is the most common primitive neuroectodermal tumour (PNET) of the central nervous system. Although supratentorial PNET (sPNET) and MB are histologically similar, their clinical behaviour differs, sPNET being more aggressive than MB. The aim of this study was to determine whether sPNET and MB are genetically different entities. METHODS AND RESULTS: We investigated 32 PNET primary tumour samples (23 MB and nine sPNET) and four PNET cell lines, for the presence of CDKN2A homozygous deletions at exon 1-alpha of p16/INK4 and exon 1-beta of p14/ARF, and promoter hypermethylation of both genes. No homozygous deletion of either p16/INK4 or p14/ARF was demonstrated in any of the PNET primary tumour samples. Methylation of p16/INK4 was found in one of six sPNET and in one of 23 MB, while p14/ARF methylation was observed in three of six sPNET and in three of 21 MB. No methylation of p16/INK4 or p14/ARF was found in any of the PNET cell lines analysed. The three MB cell lines did not show p16/INK4 expression, and only the MB Daoy cell line (homozygously deleted at CDKN2A) presented loss of p14/ARF expression. CONCLUSIONS: Our results in this limited series of central PNET show that p14/ARF is frequently involved in PNET carcinogenesis, with a higher frequency, but not statistically significant, for sPNET than for MB.

[From human andro- and parthenogenesis (hydatidiform moles and benign ovarian teratomas) to cancer]. / Des andro- et parthénogénotes humains (môles hydatiformes et tératomes ovariens) au cancer.

Genomic imprinting is a process that appeared in mammals. This phenomenon blocks the normal development of parthenogenic and androgenic conceptuses, that is to say benign ovarian teratomas and hydatidiform moles respectively. Pathological modifications of these conceptuses depend on whether the chromosomes come from the mother or father. These pathologies are associated with an accidental anomaly during gametogenesis and/or fertilizing. These reproductive anomalies are sporadic and some familial cases may exist suggesting a genetic control of such diseases. The human andro- and parthenogenetic conceptuses, but more frequently the moles, may be invasive (choriocarcinoma). An imbalance of the imprinting genes may initiate the deregulation of other genes, including oncogenes and anti-oncogenes, which can explain the cancerous modification. Immunological and environmental factors must be also considered (presence of the only paternal chromosomes in the choriocarcinoma). Numerous works on this subject are published and some recent important discoveries underline the roles of genes HOX, Tim P3, E-cad and p-16, and the recurrent chromosome anomalies 7q21+and 8p21- in the mole to choriocarcinoma processing. Although these phenomena are complex and heterogeneous, the andro- and parthenogenote conceptuses are particularly interesting models with which to understand developmental disorders and cancerous progression.

Cytogenetics, conserved synteny and evolution of chicken fucosyltransferase genes compared to human.

Fucosyltransferases appeared early in evolution, since they are present from bacteria to primates and the genes are well conserved. The aim of this work was to study these genes in the bird group, which is particularly attractive for the comprehension of the evolution of the vertebrate genome. Twelve fucosyltransferase genes have been identified in man. The orthologues of theses genes were looked for in the chicken genome and cytogenetically localized by FISH. Three families of fucosyltransferases: alpha6-fucosyltransferases, alpha3/4-fucosyltransferases, and protein-O-fucosyltransferases, were identified in the chicken with their associated genes. The alpha2-fucosyltransferase family, although present in some invertebrates and amphibians was not found in birds. This absence, also observed in Drosophila, may correspond to a loss of these genes by negative selection. Of the eight chicken genes assigned, six fell on chromosome segments where conservation of synteny between human and chicken was already described. For the two remaining loci, FUT9 and FUT3/5/6, the location may correspond to a new small syntenic area or to an insertion. FUT4 and FUT3/5/6 were found on the same chicken chromosome. These results suggest a duplication of an ancestral gene, initially present on the same chromosome before separation during evolution. By extension, the results are in favour of a common ancestor for the alpha3-fucosyltransferase and the alpha4-fucosyltransferase activities. These observations suggest a general mechanism for the evolution of fucosyltransferase genes in vertebrates by duplication followed by divergent evolution.

Assignment of FUT8 to chicken chromosome band 5q1.4 and to human chromosome 14q23.2-->q24.1 by in situ hybridization. Conserved and compared synteny between human and chicken.

The human FUT8 gene is implicated in crucial developmental stages and is overexpressed in some tumors and other malignant diseases. Based on three different experiments we have assigned the FUT8 gene to chromosome bands 14q23.2-->q24.1 and not 14q24.3 as previously shown (Yamaguchi et al., 1999). We found a high degree of identity between human and chicken FUT8 sequences. We mapped the chicken FUT8 gene to chromosome 5q1.4 in an internal rearrangement of a region of conserved synteny described between human 14q and chicken chromosome 5. Based on these findings we propose a new gene position correspondence between chicken and human comparative maps.

Asymmetrical segregation of chromosomes with a normal metaphase/anaphase checkpoint in polyploid megakaryocytes.

During differentiation, megakaryocytes increase ploidy through a process called endomitosis, whose mechanisms remain unknown. As it corresponds to abortive mitosis at anaphase and is associated with a multipolar spindle, investigation of chromosome segregation may help to better understand this cell-cycle abnormality. To examine this variation, a new method was developed to combine primed in situ labeling to label centromeres of one chromosome category and immunostaining of tubulin. Human megakaryocytes were obtained from normal bone marrow culture. By confocal microscopy, this study demonstrates an asymmetrical distribution of chromosomes (1 or 7) either between the spindle poles at anaphase stage of endomitosis and between the different lobes of interphase megakaryocyte nuclei. The metaphase/anaphase checkpoint appears normal on the evidence that under nocodazole treatment megakaryocytes progressively accumulate in pseudo-metaphase, without spontaneous escape from this blockage. Immunostaining of p55CDC/hCDC20 with similar kinetochore localization and dynamics as during normal mitosis confirms this result. HCdh1 was also expressed in megakaryocytes, and its main target, cyclin B1, was normally degraded at anaphase, suggesting that the hCdh1-anaphase-promoting complex checkpoint was also functional. This study found the explanation for these unexpected results of an asymmetrical segregation coupled to normal checkpoints by careful analysis of multipolar endomitotic spindles: whereas each aster is connected to more than one other aster, one chromosome may segregate symmetrically between 2 spindle poles and still show asymmetrical segregation when the entire complex spindle is considered.

Expression of fucosyltransferases in skin, conjunctiva, and cornea during human development.

During human development, type-1-precursor, sialyl-Le a, and Le x antigens were present in the periderm of skin and eye at week 6. The Le x antigen disappeared from cornea at 10 weeks and then from skin at 20 weeks. H-type-1, Le a, Le b, sialyl-Le a, H-type-2, sialyl-Le x, and Le y were found in cornea, conjunctiva, and periderm between 10 and 20 weeks. They disappear from the skin (at week 20) and progressively reappear in skin derivatives, especially in the epithelium of sweat glands. The secretory part of the sweat gland is type-1-precursor and H-type-1 positive while its excretory part is Le a, Le b, sialyl-Le a, and Le y positive. On the eye surface the disappearance of Le x at 10 weeks and of the H-type-1, sialyl-Le x, and Le y at week 35 starts in the central cornea in front of the lens. The corneal epithelium and the conjunctiva have similar antigens to those of excretory and secretory parts of the sweat gland, respectively. Invaginations and folding of the epidermis might preserve the embryonic staining. We propose that fucosylation patterns are associated with the embryonic origin and differentiation stage of tissue. The early and transient presence of Le x is associated with FUT4 or FUT9 activities, while the late appearance of Lewis antigens is related to other alpha3-fucosyltransferases.

FUT4 and FUT9 genes are expressed early in human embryogenesis.

The Le(x) oligosaccharide is expressed in organ buds progressing in mesenchyma, during human embryogenesis. Myeloid-like alpha3-fucosyltransferases are good candidates to synthesize this oligosaccharide. We investigated by Northern analysis all the alpha3-fucosyltransferase gene transcripts and only FUT4 and FUT9 were detected. The enzymes encoded by the FUT4 and FUT9 genes are the first alpha3-fucosyltransferases strongly expressed during the first two months of embryogenesis. The Northern profile of expression of the embryo FUT4 transcripts is similar in size and sequence to the known FUT4 transcripts of 6 kb, 3 kb, and 2.3 kb, but a new FUT9 transcript of 2501 bp, different from the known mouse (2170 bp) and human (3019 bp) transcripts was cloned. FUT3, FUT5, FUT6, and FUT7 were not detected by Northern blot. The FUT3 and FUT6 transcripts start to appear at this stage, but are only detected by reverse transcriptase-PCR analysis. The expression of FUT5 is weaker than FUT3 and FUT6 and the RT-PCR signal is faint and irregular. FUT7 is not detected at all. Using mRNA from 40- to 65-day-old embryos, we have prepared different hexamer and oligo-dT cDNA libraries and cloned, by rapid amplification cDNA ends-PCR, FUT4 and FUT9 alpha3-fucosyltransferase transcripts. The tissue expression of the embryonic FUT9 transcript is closer to that observed for the mouse (brain), than to the known human (stomach) transcripts. The acceptor specificity and the kinetics of the alpha3-fucosyltransferase encoded by this FUT9 transcript are similar to the FUT4 enzyme, except for the utilization of the lac-di-NAc acceptor which is not efficiently transformed by the FUT9 enzyme. Like FUT4, this embryonic FUT9 is N-ethylmaleimide and heat resistant and the corresponding gene was confirmed to be localized in the chromosome band 6q16. Finally, this FUT9 transcript has a single expressed exon as has been observed for most of the other vertebrate alpha2- and alpha3-fucosyltransferases.

Use of embryonic human trachea grown in nude mice to patch-repair congenital tracheal stenosis.

BACKGROUND: Long congenital tracheal stenosis is a life-threatening condition, and the available surgical treatments do not give satisfactory long-term results. METHODS: Human embryonic tracheas were implanted in the abdominal cavities of nude mice until their differentiation was completed. These differentiated tracheas were used to patch-repair surgically induced tracheal stenosis in piglets. The human, mouse, or pig origin, of all the cells in the two successive xenotransplants in the nude mouse and the pig, was determined on tissue sections by in situ hybridization with species-specific DNA probes. RESULTS: The transplanted pigs thrived and reached normal adulthood, irrespective of the administration of immunosuppressive treatment. The human tracheal tissue developed in nude mice conserved human structures, with the exception of feeding capillaries, which were of mouse origin. The tracheal patch in the adult healthy pigs comprised only pig cells organized into a fibrous scar, which was covered by normal pig epithelium. CONCLUSIONS: Results suggest that human embryonic trachea grown in nude mice can be successfully used as patch tracheoplasty for long congenital tracheal stenosis without conventional immunosuppression.

Genetic, cytogenetic and physical refinement of the autosomal recessive CMT linked to 5q31-q33: exclusion of candidate genes including EGR1.

Charcot-Marie-Tooth disease is an heterogeneous group of inherited peripheral motor and sensory neuropathies with several modes of inheritance: autosomal dominant, X-linked and autosomal recessive. By homozygosity mapping, we have identified, in the 5q23-q33 region, a third locus responsible for an autosomal recessive form of demyelinating CMT. Haplotype reconstruction and determination of the minimal region of homozygosity restricted the candidate region to a 4 cM interval. A physical map of the candidate region was established by screening YACs for microsatellites used for genetic analysis. Combined genetic, cytogenetic and physical mapping restricted the locus to a less than 2 Mb interval on chromosome 5q32. Seventeen consanguineous families with demyelinating ARCMT of various origins were screened for linkage to 5q31-q33. Three of these seventeen families are probably linked to this locus, indicating that the 5q locus accounts for about 20% of demyelinating ARCMT. Several candidate genes in the region were excluded by their position on the contig and/or by sequence analysis. The most obvious candidate gene, EGR1, expressed specifically in Schwann cells, mapped outside of the candidate region and no base changes were detected in two families by sequencing of the entire coding sequence.

Interphasic analysis of aneuploidy in cancer cell lines using primed in situ labeling.

The primed in situ (PRINS) labeling technique has been adapted to chromosomal screening of interphasic tumoral cells. A panel of ten chromosome-specific alpha-satellite DNA primers was used to evaluate numerical chromosome abnormalities in two colon cancer cell lines (Caco-2 and HT-29) and in three of their subpopulations (PF11, TC7, and HT29-MTX). In each cell line, the copy number distribution for different chromosomes showed different patterns. The observation of significant variations in the chromosome constitutions between subpopulations derived from the same original tumor suggests the common occurrence of chromosome copy number heterogeneity in tumoral cell lines. This study demonstrates that the PRINS procedure offers a simple and reliable method for in situ chromosomal screening, which could be efficiently used for karyotypic analysis of tumoral cells.

Generation of whole-chromosome painting probes specific to each chicken macrochromosome.

The realization of physical and genetic maps of the chicken genome is dependent on progress in cytogenetic knowledge of its karyotype. To help achieve this goal, we constructed amplified representative DNA samples of the chicken chromosomes 1, 2, 3, 4, 5, 6, 7, 8, Z, W and of the terminal heterochromatin part of Zq by chromosome microdissection and DOP-PCR amplification. These chromosome DNA samples, which represent about 75% of the chicken genome, were used to generate whole chromosome painting probes for FISH. The direct application of these chromosome specific probes is dual FISH localization and characterization of panels of chicken interspecific somatic hybrids. We discuss some aspects of the chicken genome and its repeated sequences.