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Context: Hyperparathyroidism-jaw tumor syndrome (HPT-JT) is an autosomal dominant syndrome with incomplete penetrance that can associate in a single patient parathyroid adenoma or carcinoma, fibro-osseous jaw tumor, cystic kidney lesion, and uterine tumor. Germline mutations of the HRPT2 gene (CDC73) coding for parafibromin are identified in approximately 50%-75% of HPT-JT cases and in approximately 14% of familial isolated hyperparathyroidism. A whole deletion of this gene has recently been reported in 1 sporadic case and in a family presenting with HPT-JT., Objective: The objective of the study was to report molecular abnormalities of the HRPT2 gene in patients with primary hyperparathyroidism in a French National cohort from the Groupe d'Étude des Tumeurs Endocrines., Methods: Patients' genomic DNA was screened by PCR-based sequencing for point mutations affecting HRPT2 and real-time quantitative PCR analysis for gross deletions., Results: We report 20 index patients with a germinal HRPT2 abnormality. Median age at diagnosis of primary hyperparathyroidism was 23 years (range 14-65 years). Median serum total calcium level at diagnosis was 3.19 mmol/L (range 2.8-4.3 mmol/L). Thirteen different mutations were identified by routine sequencing, including 7 mutations never reported. Seven patients (35%) carried a gross deletion of this gene (3 complete and 4 partial deletions). No genotype-phenotype correlation could be identified. A gross deletion of the HRPT2 gene was identified in 7% of patients for whom a routine screening by direct sequencing came up as negative., Conclusion: Gross deletion analysis of the HRPT2 gene is indicated for all patients negative for mutation, presenting with HPT-JT or familial isolated hyperparathyroidism, parathyroid carcinoma, or in patients with apparently sporadic parathyroid adenoma diagnosed at a young age, having a severe hypercalcemia.

The purpose of this study was to determine whether chromosome 10q loss is a predictor of tumor aggressiveness and poor clinical outcome in patients with oligodendroglial tumors alone or together with loss of heterozygosity (LOH) on chromosomes 1p and 19q. A microsatellite analysis was performed on sections from 130 patients with grade II and grade III oligodendroglial tumors to assess the allelic status of chromosomes 1p, 19q, and 10q, plus detailed clinical and radiological information was taken prospectively. Median age at diagnosis was 45.5 years. Seventy-eight patients had disease progression after initial therapy; median progression-free survival (PFS) was 27.5 months. Age <47 years, postoperative Karnofsky performance score >65, no contrast enhancement on MRI, grade II, and complete removal on surgery were significantly correlated with a better PFS. Median overall survival (OS) was 40.5 months. Pure oligodendroglioma and temozolomide chemotherapy were correlated with better OS. 10q LOH was correlated with anaplastic grade and 1p19q LOH correlated with pure oligodendroglioma. There was a significant association between LOH status and the tumors' response to chemotherapy: 92.3% with 1p19q LOH, 83.3% without allelic losses, 50% with 1p19q10q LOH, and 14.5% with 10q LOH. Patients with 10q LOH alone had PFS of 6 months and a 3-year survival rate of 1%, when compared with 36 months and 85%, respectively, in patients with 1p19q LOH but without 10q LOH. 1p loss was correlated with better PFS (P < .005) and OS (P = .0007), whereas 10q loss was correlated with decreased PFS (P < .0001) and OS (P < .0001). 10q LOH predicted a survival disadvantage in patients with oligodendroglial tumors irrespective of 1p/19q LOH status.

Background: According to previous studies, around 15% of patients with an apparently sporadic pheochromocytoma and a negative family history had a hereditary disease. This high frequency together with the financial support provided to reference laboratories of molecular genetics by the French government led to a nearly systematic screening in each patient with a pheochromocytoma., Objective: To check the efficiency of systematic genetic screening in patients with apparently sporadic pheochromocytoma, by analysing the 6 years experience of a multidisciplinary team in this field., Methods: One hundred patients with a pheochromocytoma-only phenotype and no family history were included. Patients with extra-adrenal tumours were excluded. Prevalence of hereditary forms was determined and analyzed according to age at onset, sex. Cost of the genetic analysis was calculated., Results: A germline mutation in one of the five susceptibility genes (VHL, RET, SDHD, SDHC, SDHB) was identified in eight patients (8%) with an age of onset between 13 and 57 years. Among them, six had a bilateral pheochromocytoma and only two had a unilateral tumour. If the guidelines for genetic screening were age of onset less than 50 or bilateral pheochromocytoma, no patients with a hereditary tumour would be missed and a 24% cost reduction would be achieved., Conclusions: According to these data, a genetic predisposition test for hereditary pheochromocytoma seems not recommended in patients with a unilateral adrenal tumour diagnosed after 50 in the absence of familial, clinical, biological or imaging features for a familial disease.

Context: Inactivating mutations of SDHD, which is mapped to 11q23 and encodes the cybS subunit of succinate dehydrogenase, predispose to hereditary paraganglioma (PGL) and/or pheochromocytoma. So far no disease was shown to occur in case of maternal transmission of a SDHD mutation, suggesting the existence of genomic imprinting. A hypothetic model, involving the loss of the maternal copy of a tumor suppressor gene mapped to 11p15 in the tumoral tissue, has been proposed to explain this mode of inheritance., Objective: Our objective was to investigate the possibility of maternal transmission of SDHD-linked PGL., Design: A three-generation family carrying the SDHD W43X mutation was studied at the clinical, pathological, and genetical levels., Results: The germline's mutation was probably inherited from the grandfather. In the second generation, three carriers (two females and one male), who had the same at risk 11q13-q23 haplotype, developed multiple cervical PGLs. In the third generation, one boy received the mutation from his mother and developed a glomus tympanicum PGL at 11 yr. He shared only the 11q23 haplotype with the other affected members of the family. Methylation analysis of the differentially methylated region upstream of the maternally expressed H19 gene, mapped to 11p15, showed that the seventh CTCF binding site is hypermethylated in the germline of the affected boy suggesting a gain of imprinting., Conclusion: Our data show that maternal transmission of a SDHD-linked PGL, even if a rare event, can occur. Therefore, we propose that children who inherited a pathogenic mutation from their mother should be considered as at risk of PGL.

Introduction: The molecular mechanism of human embryo implantation is poorly understood. The role of MUC4 mucin, present in endometrial epithelium, has never been explored, and results obtained in animal studies strongly suggest a role in implantation. We investigated the role of MUC4 in human embryo implantation., Methods and Results: We analysed the MUC4 variable number of tandem repeat (VNTR) polymorphism in three populations by Southern blot analysis: spontaneously fertile patients (C), infertile patients with repeated unexplained implantation failures after IVF (IF) and patients with a child after IVF (IVF-C). We found no differences in the size or allelic distribution of MUC4 VNTR between these three populations. We also examined, in IVF-C and IF groups, the endometrial expression of MUC4 mRNA as well as the expression of the MUC4 glycoprotein together with estrogen receptor (ER) and progesterone receptor (PR). No expression differences could be detected. However, we noticed a pattern of expression for MUC4 protein, which is limited to patches of cells in the luminal and glandular epithelium., Conclusions: We conclude that the different-sized MUC4 alleles do not interfere with implantation. The absence of coexpression of MUC4 and the steroid receptors suggests that MUC4 expression is not directly regulated by steroids.

Human mucin genes encode large O-glycoproteins, which are expressed in various epithelial tissues. The proteins are the main components of mucus, but also might be involved in morphogenesis of or carcinogenesis in many organs. We studied the expression of human mucin genes during fetal kidney development and in malformed cystic renal diseases in 10 normal fetal kidneys and 12 malformed kidneys by in situ hybridization and immunohistochemical analysis. MUC1, MUC3, and MUC6 were expressed in normal fetal kidney. MUC1 was expressed from 7.5 weeks of gestation in the metanephric blastema and throughout fetal life in the ureteric buds, distal convoluted tubules, and collecting ducts. MUC3 was expressed weakly in immature tubules from 8 weeks of gestation, after which it was expressed weakly and focally in the proximal convoluted tubules. MUC6 was expressed at 9.5 weeks of gestation in the tips of the ureteric buds and later in the collecting ducts. In malformative cystic diseases, only MUC1 expression was retained; no expression of MUC6 and MUC3 was observed. These results implicate human mucin genes (MUC1, MUC3, and MUC6) in renal morphogenesis processes.

We studied, by immunohistochemical analysis, the expression of MUC1 and epithelial membrane antigen in 44 stage pT1 renal cell carcinomas (RCCs). Six patients had a metastatic evolution. The percentage of stained cells was determined for each tumor. All tumors and normal adjacent renal parenchyma were stained. In normal kidney, distal convoluted tubules and collecting ducts stained strongly with an apical distribution. In tumors, there was a significant statistical correlation of the MUC1 expression level with the nuclear grade and with tumor progression. High-grade tumors had more stained cells than did low-grade tumors. Metastatic tumors also were more stained than nonmetastatic lesions. By using the Kaplan-Meier method and the log-rank test, we observed that patients with fewer than 10% of stained cells had no metastatic evolution. In contrast, patients with 70% or more stained cells had significantly lower metastasis-free survival rates. We conclude that MUC1 is expressed in RCC and is associated with tumor progression in pT1 RCC.

Alpha1-antitrypsin (alpha1AT) deficiency is an autosomal recessive disorder that can cause pulmonary emphysema and liver disease. We report here the case of a 59-year-old woman who was admitted to hospital for evaluation of jaundice. She had no history of hepatitis or childhood liver disease. She had never received a blood transfusion, nor had she abused drugs or alcohol. Transjugular liver biopsy was then performed and revealed a micronodular cirrhosis. Ten months later, because of persistent liver cell failure and ascites, she underwent an orthotopic liver transplantation. Investigation of alpha1AT system in the proband revealed a substantial decrease in serum alpha1AT associated with a low elastase inhibitory capacity. The Pi phenotype revealed a PiM-like profile. Sequencing of exons 1-5 demonstrated the presence of the M3 allele. Moreover, a triple nucleotide deletion was detected in exon 2 of one allele. This caused an "in-phase" frameshift, coding for a protein deficient in a single Phe residue, which corresponded to the Mmalton variant. After liver biopsy, periodic acid-Schiff-positive acidophilic bodies resistant to diastase digestion were observed in the cytoplasm of hepatocytes. These results demonstrated that our patient had a heterozygous M3Mmalton alpha1AT genotype related to a deficiency phenotype. This observation is the first of a patient with heterozygous Mmalton genotype associated with an alpha1AT deficiency that induced severe liver disease requiring orthotopic liver transplantation.

Mucins, the major component of mucus, contain tandemly repeated sequences that differ from one mucin to another. Considerable advances have been made in recent years in our knowledge of mucin genes. The availability of the complete genomic and cDNA sequences of MUC5B, one of the four human mucin genes clustered on chromosome 11, provides an exemplary model for studying the molecular evolution of large mucins. The emerging picture is one of expansion of mucin genes by gene duplications, followed by internal repeat expansion that strictly preserves frameshift. Computational and phylogenetic analyses have permitted the proposal of an evolutionary history of the four human mucin genes located on chromosome 11 from an ancestor gene common to the human von Willebrand factor gene and the suggestion of a model for the evolution of the repeat coding portion of the MUC5B gene from a hypothetical ancestral minigene. The characterization of MUC5B, a member of the large secreted gel-forming mucin family, offers a new model for the comparative study of the structure-function relationship within this important family.

Our goal was to determine the effect of transdermal nicotine on cytokine and mucin gene transcription in ulcerative colitis (UC). Sixty-four nonsmoking patients with active UC were randomly assigned to transdermal nicotine (maximum dose 22 mg/day) or placebo for 4 weeks. Clinical assessment and colonic mucosal biopsies were obtained at entry and after 4 weeks. Inflammatory and immunoregulatory cytokines were assessed by qualitative reverse transcriptase-polymerase chain reaction (RT-PCR). Based on this initial screen. IL-8 mRNA levels were measured by RT-competitive PCR. MUC1, MUC2, MUC3, MUC4, MUC5AC, MUC5B, and MUC6 mRNA concentrations were measured by quantitative dot blot analysis. Cytokine mRNA expression, except for IL-8, was similar in all patients. IL-8 mRNA levels were significantly decreased in the colonic mucosa of nicotine-treated patients who improved (p = 0.04). IL-8 mRNA values were similar before and after treatment in nonresponding nicotine-treated patients and in all placebo-treated patients. Mucin gene expression was similar in all patient groups. Beneficial effects of transdermal nicotine in active UC may result from decrease of IL-8 expression at the transcriptional level. Transdermal nicotine has no effect on mucin gene transcription.

Familial medullary thyroid carcinoma (FMTC) and multiple endocrine neoplasia type 2A syndromes are dominantly inherited diseases caused by activating germline mutations of the RET protooncogene. The majority of these patients carry a germline point mutation affecting one of five cysteine residues encoded by exon 10 (codon 609, 611, 618, or 620) or 11 (codon 634). In a few FMTC families, point mutations involving noncysteine codons in exon 13 (codons 768, 790, and 791), 14 (codon 804), or 15 (codon 891) have been reported. Hirschsprung's disease is a nonneoplastic disorder associated with RET mutations leading to a loss of function effect. Mutations are identified in 50% of the familial cases and are scattered along the gene. We now report the study of a FMTC family with four affected members and a history of fatal neonatal intestinal obstruction in the sister of the proband. Genetic analysis demonstrated the absence of an usual FMTC mutation and the presence of a germline 9-bp duplication in RET exon 8 in the heterozygous state in all patients with MTC. This new mutation creates an additional cysteine residue in the extracellular cysteine-rich domain of RET. Further studies are warranted to confirm whether this new mutation is causing MTC only or could be associated with Hirschsprung's disease.

Alterations in the structure and/or quantity of mucins could alter the barrier function of mucus and play a role in initiating and maintaining mucosal inflammation in Crohn's disease. To investigate the hypothesis of a mucin gene defect in Crohn's disease, we analyzed the expression of the different mucin genes in the ileal mucosa of patients with Crohn's disease and controls. mRNA expression levels were assessed by a quantitative dot blot analysis and compared (i) between healthy and involved ileal mucosa of patients with Crohn's disease and (ii) between healthy mucosa of patients with Crohn's disease and controls. Expression of the different mucin genes was heterogeneous among controls and patients with Crohn's disease, except for MUC6 in controls. Nevertheless, MUC1 mRNA expression was significantly decreased in the involved ileal mucosa of patients with Crohn's disease when compared to the healthy mucosa (p = 0.02). Moreover, the expression levels of MUC3, MUC4, and MUC5B were significantly lower in both healthy and involved ileal mucosa of patients with Crohn's disease compared to controls (p < or = 0.05). The decrease of expression levels of some mucin genes (more particularly MUC3, MUC4, and MUC5B) in both healthy and involved ileal mucosa suggests a primary or very early mucosal defect of these genes in CD.

In the human uterine endocervix, five out of the six human mucin genes investigated (MUC 2, MUC 3, MUC 4, MUC 5AC, MUC 5B and MUC 6) are expressed, whereas in some other mucosae the hybridization pattern demonstrates the expression of only two or three of these genes. The most intense labelling by in-situ hybridization is obtained significantly with MUC 4, predominantly during the luteal phase. The expression of the MUC 4 gene appears to be influenced by the oestro-progesterone ratio. During the ovulatory cycle, there are only a few differences concerning the variations of expression of all other MUC genes.

We describe a new specific method for measuring lecithin, sphingomyelin, and phosphatidylglycerol in amniotic fluid by thin-layer chromatography, with use of a hydrogen flame ionization detector. After extraction and acetone precipitation to isolate surface-active lecithin, the phospholipids are separated on a thin rod of refractory and chemically stable material, having an outer coating of a bonded, sintered partition medium. Two solvent systems are used to develop the chromatograms, chloroform/methanol/water to separate lecithin and sphingomyelin, tetrahydrofuran/methylal/methanol for phosphatidylglycerol. Then the rod is passed through an hydrogen flame; the resulting ions produced generate a current, which is amplified and fed to a potentiometric recorder. The height of integral curves was proportional to the area under each peak. For quantitation we used an internal standard (lysolecithin in the first system. phosphatidyldimethylethanolamine in the second). The method requires less than 5 mL of amniotic fluid; results are available within 6 h.

During organic acid screening by gas chromatography/mass spectrometry, we detected a large peak corresponding to glyceric acid in a patient's urine sample. The D(+) configuration was demonstrated by a polarimetric method and by enzymatic stereospecificity of D-glycerate dehydrogenase (EC 1.1.1.29). We biochemically investigated this fifth reported case of D-glyceric acidemia. In our patient, loading tests with L-serine and fructose led to an increase of D-glyceric acid in both plasma and urine. Determination of other metabolites involved in D-glycerate metabolism revealed no abnormality in any sample examined. After comparing all our results with those of the preceding observations described in the literature, we suggest a possible enzymatic defect located on one of the metabolic pathways shared by fructose and L-serine, possibly at the level of hepatic D-glycerate kinase (EC 2.7.1.31). Nevertheless, a primary defect of L-serine catabolism cannot be entirely excluded.