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Background Diffuse H3 K27M-mutant gliomas occur primarily in children but can also be encountered in adults. The aim of this study was to describe the characteristics of H3 K27M-mutant gliomas in adults. Methods We analyzed the characteristics of 21 adult H3 K27M-mutant gliomas and compared them with those of 135 adult diffuse gliomas without histone H3 and without isocitrate dehydrogenase (IDH) mutation (IDH/H3 wild type). Results The median age at diagnosis in H3 K27M-mutant gliomas was 32 years (range: 18-82 y). All tumors had a midline location (spinal cord n = 6, thalamus n = 5, brainstem n = 5, cerebellum n = 3, hypothalamus n = 1, and pineal region n = 1) and were IDH and BRAF-V600E wild type. The identification of an H3 K27M mutation significantly impacted the diagnosis in 3 patients (14%) for whom the histological aspect initially suggested a diffuse low-grade glioma and in 7 patients (33%) for whom pathological analysis hesitated between a diffuse glioma, ganglioglioma, or pilocytic astrocytoma. Compared with IDH/H3 wild-type gliomas, H3 K27M-mutant gliomas were diagnosed at an earlier age (32 vs 64 y, P < .001), always had a midline location (21/21 vs 21/130, P < .001), less frequently had a methylated MGMT promoter (1/21 vs 52/129, P = .002), and lacked EGFR amplification (0/21 vs 26/128, P = .02). The median survival was 19.6 months in H3 K27M-mutant gliomas and 17 months in IDH/H3 wild-type gliomas (P = .3). Conclusion In adults, as in children, H3 K27M mutations define a distinct subgroup of IDH wild-type gliomas characterized by a constant midline location, low rate of MGMT promoter methylation, and poor prognosis.

The aim of this article is to clarify the epidemiologic, clinical, endoscopic, biological and genetic characteristics of type 1 serrated polyposis patients.Consecutive patients responding to the WHO definition of type 1 serrated polyposis in one reference center for polyposis patients accepted genetic counseling. Detailed data on previous endoscopies, histology, and life habits were recorded, after informed consent, germline analysis of MUTYH, APC, and PTEN germline mutations. Molecular biology was tested on available fixed tissue from different lesion types.We included 29 patients (mean age 53.5 years, 21 women (72.4%)), four with a personal history of colorectal cancer (CRC), with a mean of 11.6 SSAs, with associated hyperplastic polyps in 93.1% and adenomas in 82.8%. SSAs showed no dysplasia in 46.9% of lesions (three of 29 patients), LGD in 51.9% (22/29 patients), and HGD in 1.2% (four of 29 patients). Dysplasia was more frequent in proximal SSAs and in women. Colectomy 15 patients (51.7%), upper digestive neoplasms: eight patients (27.5%); smokers: 24 patients (82.8%); family history of CRC: 16 patients (55.2%). Biology: MSI-H phenotype in one SSA, V600E BRAF mutation in 95% of SSAs; MGMT hypermethylation in three of 17 SSAs. No germline mutation was detected in MYH, APC or PTEN genes.Type 1 serrated polyposis corresponds to a majority of women, with a high prevalence of smokers, a high prevalence of dysplastic serrated adenomas, particularly in females, without identified germline mutation in targeted predisposing genes.

// Julien Bollard 1, * , Patrick Massoma 1, * , Cecile Vercherat 1 , Martine Blanc 1 , Florian Lepinasse 2 , Nicolas Gadot 3 , Christophe Couderc 1 , Gilles Poncet 4 , Thomas Walter 4 , Marie-Odile Joly 1, 2, 5 , Valerie Hervieu 1, 2, 5 , Jean-Yves Scoazec 1, 2, 3, 5 , Colette Roche 1 1 Centre de Recherche en Cancerologie de Lyon, INSERM U1052, CNRS UMR5286, Equipe «Differenciation endocrine et tumorigenese», Faculte Laennec, F-69372 Lyon, France 2 Hospices Civils de Lyon, Hopital Edouard Herriot, Service Central d’Anatomie et de Cytologie Pathologiques, F-69437 Lyon, France 3 Universite Lyon 1, Federation de Recherche Sante Lyon-Est, ANIPATH, Faculte Laennec, F-69372 Lyon, France 4 Hospices Civils de Lyon, Hopital Edouard Herriot, Federation des Specialites Digestives, F-69437 Lyon, France 5 Universite de Lyon, Universite Lyon 1, F-69622 Villeurbanne, France * These authors have contributed equally to this work Correspondence to: Colette Roche, e-mail: colette.roche@inserm.fr Keywords: small intestine neuroendocrine tumor, semaphorin, proliferation, tumor progression Received: May 20, 2015 Accepted: September 21, 2015 Published: October 02, 2015 ABSTRACT Gastro-intestinal neuroendocrine tumors (GI-NETs) are rare neoplasms, frequently metastatic, raising difficult clinical and therapeutic challenges due to a poor knowledge of their biology. As neuroendocrine cells express both epithelial and neural cell markers, we studied the possible involvement in GI-NETs of axon guidance molecules, which have been shown to decrease tumor cell proliferation and metastatic dissemination in several tumor types. We focused on the role of Semaphorin 3F (SEMA3F) in ileal NETs, one of the most frequent subtypes of GI-NETs. SEMA3F expression was detected in normal neuroendocrine cells but was lost in most of human primary tumors and all their metastases. SEMA3F loss of expression was associated with promoter gene methylation. After increasing endogenous SEMA3F levels through stable transfection, enteroendocrine cell lines STC-1 and GluTag showed a reduced proliferation rate in vitro . In two different xenograft mouse models, SEMA3F-overexpressing cells exhibited a reduced ability to form tumors and a hampered liver dissemination potential in vivo . This resulted, at least in part, from the inhibition of mTOR and MAPK signaling pathways. This study demonstrates an anti-tumoral role of SEMA3F in ileal NETs. We thus suggest that SEMA3F and/or its cellular signaling pathway could represent a target for ileal NET therapy.

BACKGROUND The alkylating agents (ALKYs) streptozotocin, dacarbazine, and temozolomide currently are the main drugs used in systemic chemotherapy for neuroendocrine tumors (NETs). The promising activity shown by gemcitabine and oxaliplatin (GEMOX) in previous studies prompted this study 1) to confirm the use of GEMOX in a larger population of NET patients, 2) to compare its efficacy with that of ALKYs, and 3) to explore whether the O6-methylguanine-DNA methyltransferase (MGMT) status could help in selecting the chemotherapy regimen. METHODS One hundred four patients with metastatic NETs (37 pancreatic NETs, 33 gastrointestinal NETs, 23 bronchial NETs, and 11 NETs of other/unknown origin) were treated with GEMOX between 2004 and 2014. Among these patients, 63 also received ALKYs. MGMT promoter gene methylation was assessed via pyrosequencing in 42 patients. RESULTS Patients received a median of 6 courses of GEMOX. Twenty-four (23%) had an objective response (OR). The median progression-free survival (PFS) and overall survival were 7.8 and 31.6 months, respectively. In the 63 patients treated with both ALKYs and GEMOX, the ORs (22% and 22%) and the PFSs (7.5 and 7.3 months) were similar. The response was concordant in 53% of the patients. Promoter gene methylation of MGMT was associated with better outcomes with ALKYs (P = .03 for OR and P = .04 for PFS) but not GEMOX. CONCLUSIONS GEMOX is effective against NETs; its activity is comparable to that of ALKYs, and it is not influenced by the MGMT status. Our data suggest that GEMOX might be preferred for patients with unmethylated MGMT tumors. Cancer 2015;121:3435–43. © 2015 American Cancer Society.

IF 1.590; International audience; Background: The tumor spectrum in the Lynch syndrome is well defined, comprising an increased risk of developing colonic and extracolonic malignancies. Muir-Torre syndrome is a variant with a higher risk of skin disease. Patients have been described carrying mutations in the mismatch repair genes and presenting tumors with unusual histology or affected organ not part of the Lynch syndrome spectrum. Hence, the real link between Lynch syndrome, or Muir-Torre syndrome, and these tumors remains difficult to assess.Case presentation: We present the case of a 45-year-old-woman, diagnosed with breast cancer at 39 years of age and skin squamous cell carcinoma (SCC) at 41 years of age, without personal history of colorectal cancer. The microsatellite instability analysis performed on the skin SCC showed a low-level of microsatellite instability (MSI-Low). The immunohistochemical expression analysis of the four DNA mismatch repair proteins MLH1, MSH2, MSH6 and PMS2 showed a partial loss of the expression of MSH2 and MSH6 proteins. Germline deletion was found in MSH2 gene (c.1277-? _ 1661 + ?del), exon 8 to 10. Then, at 45 years of age, she presented hyperplastic polyps of the colon and a sebaceous adenoma.Conclusion: Squamous cell carcinomas have been described in Lynch syndrome and Muir- Torre syndrome in two studies and two case reports. This new case further supports a possible relationship between Lynch syndrome and squamous cell carcinoma.

Cerebellar gangliocytoma can correspond to Lhermitte-Duclos disease, a benign hamartomatous malformation encountered in young adults. It can also be a part of gangliogliomas/gangliocytomas family, which usually encompasses temporal pediatric neoplasms associated with longstanding seizures. We report a case of a young 11-year-old patient who presented with a gangliocytoma of the cerebellum revealed by neurologic manifestations (headache, dyspraxia, equilibrium and gait disturbances). Diagnosis was made on surgical material. Tumour was characterized by dysplastic mature ganglion cells, perivascular lymphocytic infiltrates and no glial neoplastic component. By immunohistochemistry, ganglion cells expressed neurofilaments, MAP2 protein, synaptophysin, chromogranin A and S100 protein. BRAF V600E mutation was absent. Clinical characteristics, radiology, histopathology of the two main diagnoses are discussed.

International audience; Background: The goal of this prospective multicentric trial was to validate a technique that allowed for MGMT promoter methylation analysis in routine clinical practice.Methods: The MGMT status of 139 glioblastoma patients, whom had received standard first line treatment, was determined using pyrosequencing (PSQ) and a semi-quantitative Methylation-specific PCR (sqMS-PCR) method, using both frozen and formalin-fixed paraffin-embedded FFPE samples. Eight participating centers locally performed the analysis, including external quality controls.Results: There was a strong correlation between results from FFPE and frozen samples. With cut-offs of 12% and 13%, 98% and 91% of samples were identically classified with PSQ and sqMS-PCR respectively. In 12% of cases frozen samples were excluded because they had a low percentage of tumor cells. In 5-6% of cases the analysis was not feasible on FFPE samples. The optimized risk cut-offs were higher in both techniques when using FFPE samples, in comparison to frozen samples. For sqMS-PCR, we validated a cut-off between 13-15% to dichotomize patients. For PSQ, patients with a low level of methylation (

The pharmacomodulation of the N atom of alpha,beta-acetylenic aminothiolesters or the replacement of the thiolester moiety by more electrophilic groups did not permit any clear rationale to be established for improving the selective growth-inhibitory activity of this family of compounds over that of the previously synthesized alpha,beta-acetylenic aminothiolesters DIMATE and MATE [G. Quash, G. Fournet, J. Chantepie, J. Goré, C. Ardiet, D. Ardail, Y. Michal, U. Reichert, Biochem Pharmacol 64 (2002) 1279-92]. Hence DIMATE and MATE were investigated more thoroughly for selectivity and growth-inhibitory activity using human prostate epithelial normal cells (HPENC) on the one hand and human prostate epithelial cancer cells (DU145) on the other. Unequivocal evidence was obtained showing that both compounds were reversible growth inhibitors of HPENC but irreversible growth inhibitors of DU145. Growth-inhibition of DU145 was due to the induction of early apoptosis as revealed by the flow cytometric analytical profile of inhibitor-treated cells, of the decrease in the redox potential and increase in superoxide anion content of their mitochondria. Of the two intracellular enzymes: aldehyde dehydrogenases 1 and 3 (ALDH1 and ALDH3) targeted by DIMATE and MATE, ALDH3 was inhibited to the same extent by both compounds whereas ALDH1 was less susceptible to inhibition by MATE. As the induction of ALDH3 by xenobiotics is hormone-dependent, MATE, the more selective of the two inhibitors, is a useful tool not only for examining the role of the ALDH3 isoform in hormone-sensitive and resistant prostate cancer cells in culture but also for investigating if it can inhibit the growth of xenografts of prostate cancer in immunodeficient mice.

The alkylating agents (ALKYs) streptozotocin, dacarbazine, and temozolomide currently are the main drugs used in systemic chemotherapy for neuroendocrine tumors (NETs). The promising activity shown by gemcitabine and oxaliplatin (GEMOX) in previous studies prompted this study 1) to confirm the use of GEMOX in a larger population of NET patients, 2) to compare its efficacy with that of ALKYs, and 3) to explore whether the O(6) -methylguanine-DNA methyltransferase (MGMT) status could help in selecting the chemotherapy regimen.One hundred four patients with metastatic NETs (37 pancreatic NETs, 33 gastrointestinal NETs, 23 bronchial NETs, and 11 NETs of other/unknown origin) were treated with GEMOX between 2004 and 2014. Among these patients, 63 also received ALKYs. MGMT promoter gene methylation was assessed via pyrosequencing in 42 patients.Patients received a median of 6 courses of GEMOX. Twenty-four (23%) had an objective response (OR). The median progression-free survival (PFS) and overall survival were 7.8 and 31.6 months, respectively. In the 63 patients treated with both ALKYs and GEMOX, the ORs (22% and 22%) and the PFSs (7.5 and 7.3 months) were similar. The response was concordant in 53% of the patients. Promoter gene methylation of MGMT was associated with better outcomes with ALKYs (P = .03 for OR and P = .04 for PFS) but not GEMOX.GEMOX is effective against NETs; its activity is comparable to that of ALKYs, and it is not influenced by the MGMT status. Our data suggest that GEMOX might be preferred for patients with unmethylated MGMT tumors. Cancer 2015;121:3435-43. © 2015 American Cancer Society.

The involvement of mutated androgen receptors (mut-AR) in the actions of estrogens in prostate cancer cells is controversial. This work was designed to determine the role of such receptors in the growth inhibition by estradiol (E2) and androgens of the MOP cell line, a derivative of the LNCaP cell line. Diethylstilbestrol (DES) was used as a “tool”. E2 like DHT and R1881 inhibits MOP cell proliferation while DES does not. E2 and R1881 down regulate mut-AR mRNA, DES does not. E2 enhances mut-AR transcriptional activity less efficiently than R1881 while DES does not. E2 and R1881 up regulate PSA secretion in a dose-dependent manner, DES does it marginally at 10 −6 M. MOP cells express low amounts of ERα and ERβ mRNA but neither DES nor E2 and R1881 do enhance ER transcriptional activity. DES and E2 bind to mut-AR with relative binding affinities which are respectively 1/175 and 1/10 that of DHT. The E2 and androgen-repressed proliferation is prevented by DES and by the anti-androgen bicalutamide. In LNCaP cells, DES prevents the androgen-enhanced proliferation. These results strongly suggest that: (a) the putative endogenous ERs are biologically inactive in MOP cells, (b) the E2-repressed proliferation results from hormone binding to mut-AR and, (c) DES is an anti-androgen in mut-AR expressing cell line.

The three mammalian receptors UNC5H1, UNC5H2, and UNC5H3 (also named UNC5A, UNC5B, and UNC5C in human) that belong to the family of the netrin-1 receptors, UNC5H, were initially proposed as mediators of the chemorepulsive effect of netrin-1 on specific axons. However, they were also recently shown to act as dependence receptors. Such receptors induce apoptosis when unbound to their ligand. We show here that the expression of the human UNC5A, UNC5B, or UNC5C is down-regulated in multiple cancers including colorectal, breast, ovary, uterus, stomach, lung, or kidney cancers. In colorectal tumors, this down-regulation is associated with loss of heterozygosity occurring within UNC5A , UNC5B , and UNC5C genes but may also be partially related to epigenetic processes because histone deacetylase inhibitor increased UNC5C expression in various cancer cell lines. Moreover, sequencing of UNC5C gene in patients with colorectal tumors revealed the presence of missense mutations. The loss/reduction of expression may be a crucial mechanism for tumorigenicity because the expression of UNC5H1, UNC5H2, or UNC5H3 inhibits tumor cell anchorage-independent growth and invasion. Moreover, these hallmarks of malignant transformation can be restored by netrin-1 addition or apoptosis inhibition. Hence, UNC5H1, UNC5H2, and UNC5H3 receptors may represent tumor suppressors that inhibit tumor extension outside the region of netrin-1 availability by inducing apoptosis.

Sebaceous neoplasms are a major clinical feature of Muir-Torre syndrome (MTS) associated with visceral malignancies, especially colorectal and endometrial tumors. The diagnosis of MTS relies largely on the microsatellite instability (MSI) phenotype in tumors, suggesting germline mutations in DNA mismatch repair (MMR) genes responsible for the inherited disease. We hypothesized that in some MSI-H sebaceous tumors, acquired rather than inherited mutations in MMR genes could be involved. Using next-generation sequencing, we screened MMR gene mutations in 18 MSI-H sebaceous tumors. We found mutations in 17 samples (94%). Indeed, 12/17 (71%) were shown to carry acquired somatic mutations and among 12 samples, seven were shown to be associated with additional somatic alterations like loss of heterozygosity or multiple mutations, suggesting somatic second hits. Our findings strongly suggest that somatic MMR deficiency is responsible for a proportion of MSI-H sebaceous tumors.

The responses, in terms of cell proliferation and c- myc messenger RNA content, of human prostate cancer cells to androgen-receptor ligands were investigated. Experiments were performed with three types of cells (LNCaP, R2 and MOP) and three compounds (the androgen R 1881 and two antiandrogens: cyproterone acetate, CYPA, and RU 56187). MOP cells were established in the laboratory and the effects of RU 56187 had not been studied in culture. In terms of proliferation, LNCaP was stimulated by the three compounds, R2 was inhibited by R 1881 and RU 56187 but was stimulated by CYPA while MOP was inhibited by the three compounds. In the three types of cells, c- myc messenger RNAs were down regulated by R 1881 and RU 56187 but not by CYPA. The conclusions are: (1) the sets of responses of cell proliferation to three androgen-receptor ligands are cell specific; (2) the control of c- myc messenger RNA by R 1881 and RU 56187 may be related to the inhibition of cell proliferation by these compounds but not to their stimulatory effect on cell proliferation; (3) if prostate tumor cells would respond in vivo to androgens and antiandrogens like in culture, patients with prostate cancer could take benefits of reversible medical castration and sequential prescription of various antiandrogens.

We compared the metabolic effects of recombinant human (rh) insulin-like growth factor (IGF)-1 or a combination of rhIGF-1 + rh growth hormone (GH) on resting energy expenditure (REE) in 8 maintenance hemodialysis (MHD) patients. Seven males and 1 female (aged 41.6 ± (SD) 12.4) with no evidence of malnutrition (BMI 21.6 ± 2.2 kg/m2, serum albumin 45 ± 2 g/l, serum IGF-1 359 ± 165 µg/l) received either rhIGF-1 (80 µg/kg/day) or rhIGF-1 (80 µg/kg/day) + rhGH (50 µg/kg/day) for 3 days in a random crossover design. REE and the respiratory quotient (RQ) were measured at rest before and after the 3-day treatment. The results confirmed that MHD patients have a REE not different from normal individuals. REE was strongly correlated with lean body mass but not with fat mass. rhIGF-1 treatment did not modify REE despite doubling serum IGF-1 values, whereas a combined rhIGF1 + rhGH treatment significantly increased REE by 11% (p < 0.001). There was no change in RQ under both treatments, in response to a proportionate increase in VCO2 and VO2. These results show that energy expenditure is mainly dependent upon lean body mass in well-nourished MHD patients. The metabolic effects of rhIGF-1 and rhGH on energy expenditure may differ in response to their opposite effects on lipid oxidation and insulin regulation.

International audience; ContextMultiple Endocrine Neoplasia Type 1 (MEN1) is an autosomal dominant inherited syndrome, related to mutations in the MEN1 gene. Controversial data suggest that the nonsynonymous p.Ala541Thr variant, usually considered as a non-pathogenic polymorphism, may be associated with an increased risk of MEN1-related lesions in carriers.ObjectiveThe aim of this study was to evaluate the pathogenic influence of the p.Ala541Thr variant on clinical and functional outcomes.Patients and methodsWe analysed a series of 55 index patients carrying the p.Ala541Thr variant. Their clinical profile was compared to that of 117 MEN1 patients. The biological impact of the p.Ala541Thr variant on cell growth was additionally investigated on menin-deficient Leydig cell tumour (LCT)10 cells generated from Men1+/Men1− heterozygous knock-out mice, and compared with wild type (WT).ResultsThe mean age at first appearance of endocrine lesions was similar in both p.Ala541Thr carriers and MEN1 patients, but no p.Ala541Thr patient had more than one cardinal MEN1 lesion at initial diagnosis. A second MEN1 lesion was diagnosed in 13% of MEN1 patients and in 7% of p.Ala541Thr carriers in the year following preliminary diagnosis. Functional studies on LCT10 cells showed that overexpression of the p.Ala541Thr variant did not inhibit cell growth, which is in direct contrast to results obtained from investigation of WT menin protein.ConclusionTaken together, these data raise the question of a potential pathogenicity of the p.Ala541Thr missense variant of menin that commonly occurs within the general population. Additional studies are required to investigate whether it may be involved in a low-penetrance MEN1 phenotype.; ContexteLa néoplasie endocrinienne multiple de type 1, NEM1, est une affection à transmission autosomique dominante qui associe chez un même patient ou ses apparentés des tumeurs des parathyroïdes, du pancréas endocrine et de l’hypophyse. Des données controversées suggèrent que le variant Ala541Thre pourrait avoir un rôle pathogénique, et pourrait être associé à un risque accru de développer des lésions de MEN1.ObjectifsLe but de cette étude était d’évaluer les atteintes cliniques et fonctionnelles du variant p.Ala541Thr.Patients et méthodesNous avons analysé une série de 55patients porteurs du variant p.Ala541Thr. Leur présentation clinique a été comparée à celle de 117patients MEN1. L’effet biologique de ce variant sur la croissance cellulaire a été également étudié dans un modèle cellulaire issus de tumeurs de cellules de Leydig déficientes en MEN1 (LCT10).RésultatsL’âge moyen à la première lésion est similaire dans les 2groupes p.Ala541Thr et MEN1, mais aucun des patients p.Ala541Thr n’avait plus d’une lésion au diagnostic. Une deuxième lésion a été diagnostiquée chez 13% des MEN1et 7% des p.Ala541Thr l’année qui a suivi le diagnostic initial. Les études fonctionnelles montrent que la réexpression du variant p.Ala541Thr ne permet pas d’inhiber la croissance cellulaire, contrairement à ce qui a été observé avec la protéine sauvage.ConclusionsCe travail vient perturber le concept de polymorphisme et de leur potentielle non-pathogénicité. Des études complémentaires sont cependant nécessaires afin de déterminer si ce variant peut-être impliqué dans la survenue d’un phénotype MEN1de faible pénétrance.

The effects of a low-protein diet on the serum insulin-like growth factor (IGF)-1 and IGF binding proteins (IGFBP) were investigated during a 3-month controlled study in 12 adult chronic renal failure patients. Six patients were randomly supplemented with keto acids (Cetolog, Clintec, Velizy, France). Protein intake was prescribed so that both groups were isonitrogenous. Dietary survey included a monthly 3-day food record and a 24-h urinary urea measurement. After a 4- to 6-wk equilibrium period (1.11 g of protein, 32 kcal/kg body wt per day), patients reduced their protein intake to 0.71 g protein/kg body wt per day. Energy intake was kept constant (31 kcal/kg body wt per day) during the 3-month period. Serum IGF-1 levels were in normal range and, for 11 of the 12 patients, were correlated with the GFR (P = 0.01). These serum IGF-1 values did not decrease after reducing the protein intake. By Western ligand blotting, serum IGFBP1, IGFBP2, and IGFBP4 levels were significantly higher than normal adults, whereas the IGFBP3 level was not increased. IGFBP were not modified when protein intake was reduced. The IGFBP1 level was elevated despite a normal insulin level. IGFBP4 changes were inversely correlated with IGF-1 variations. There was no difference between groups receiving or not receiving the keto acids. Thus, in adult chronic renal failure, reducing protein intake by 40% did not modify the growth hormone/IGF-1/IGFBP axis.

Ten percent of paragangliomas are malignant and one-third occurs in a genetic background. We report a case of succinate dehydrogenase subunit B (SDHB)-related malignant paraganglioma with dramatic response to temozolomide and capecitabine regimen (decrease in tumor size of 70% with RECIST criteria). Tumor cells harbored a new mutation in SDHB gene and showed aberrant hypermethylation of O6-methylguanine-DNA-methyltransferase promoter. Our report suggests the importance of molecular predictive factors of response for the selection of chemotherapeutic as well as targeted agents. This observation points to a possible genotype response to treatment relationships, which could help to design tailor-made treatments in the future.

International audience; Constitutional epimutation is one of the causes for MLH1 gene inactivation associated with hereditary non-polyposis colon cancer (HNPCC) syndrome. Here we investigate MLH1 promoter hypermethylation in 110 sporadic early-onset colorectal cancer patients. Variable levels of hypermethylation were detected in 55 patients (50%). Importantly a reduced MLH1 gene expression was found in patients with high-level methylation, with the association of microsatellite instability (MSI) in their tumor cells. Such high-level methylation accounts for 7.4% of all patients included in this study. Furthermore, we found that in one case constitutional methylation affected both alleles, indicating a post-zygotic methylation dysregulation. Our findings suggest that constitutional epimutation is a mechanism underlying early-onset colorectal cancer, although it is involved in only a small proportion of patients, who require appropriate surveillance. Our findings provide further insight into the role of aberrant constitutional methylation in colon carcinogenesis and raise the question of whether prevalent low-level methylation constitutes a potential risk factor for cancer development.

From an MtTF 4 pituitary tumor we established new cell lines and tumors whose growth is sensitive (stimulation or inhibition) or insensitive to estradiol (Cancer Res., 1991, 50, 3786–3794). The main objective of the present work was to determine whether such a diversity of responses is correlated with the estradiol control of kallikrein gene expression. From kallikrein mRNA analyses and from kallikrein activity assays in conditioned medium it appears highly probable that the diversity of responses to estradiol of pituitary tumors and cell growth is not due to a differential regulation of kallikrein gene expression. In addition, prolactin gene expression and estrogen receptor mRNA have been studied to further characterize this experimental model.

The actin-binding protein gelsolin is involved in cell motility via the regulation of actin cytoskeleton, and its expression is modified in several human cancers. However, the potential implication of this protein in colorectal carcinogenesis is debated. By using immunohistochemistry, we studied gelsolin expression in 69 cases of colon adenocarcinomas and in 72 lesions representative of the different stages of colonic tumorigenesis. In addition, we performed Northern blot analysis of gelsolin messenger RNA in 12 paired samples of human colon cancer and normal corresponding mucosa. Gelsolin protein and messenger RNA expressions were severely down-regulated in all adenocarcinomas tested. Moreover, gelsolin protein was down-regulated in a large proportion of high-grade adenomas (14/16) before the acquisition of invasive properties but in only a small proportion of low grade adenomas and serrated adenomas (2/30) and in none of the 9 cases of nonneoplastic hyperplastic polyps tested. Our results therefore demonstrate that gelsolin down-regulation is an early and almost constant event in colon carcinogenesis and is associated with the transition from adenoma to carcinoma.

Since the first report by our group in 1999, more than 20 unrelated biallelic mutations in DNA mismatch repair genes (MMR) have been identified. In the present report, we describe two novel cases: one carrying compound heterozygous mutations in the MSH6 gene; and the other, compound heterozygous mutations in the PMS2 gene. Interestingly, the inactivation of one PMS2 allele was likely caused by gene conversion. Although gene conversion has been suggested to be a mutation mechanism underlying PMS2 inactivation, this is the first report of its involvement in a pathogenic mutation. The clinical features of biallelic mutation carriers were similar to other previously described patients, with the presence of cafe-au-lait spots (CALS), early onset of brain tumors, and colorectal neoplasia. Our data provide further evidence of the existence, although rare, of a distinct recessively inherited syndrome on the basis of MMR constitutional inactivation. The identification of this syndrome should be useful for genetic counseling, especially in families with atypical hereditary nonpolyposis colon cancer (HNPCC) associated with childhood cancers, and for the clinical surveillance of these mutation carriers.

Most prostate cancers escape endocrine therapy by diverse mechanisms. One of them might be growth repression by androgen. We reported that androgen represses the growth in culture of MOP cells (a sub-line of LNCaP cells) and that of MOP cell xenografts, although tumor growth becomes androgen-independent (AI). Here we explore whether AI tumors contain androgen-responsive cells. ME carcinoma cells were established from AI tumors. The responses to androgen were examined by cell counting, DAPI labeling, flow cytometry, PSA immunoassay and tumor size follow-up. Androgen receptors (AR) were analyzed by western blotting and DNA sequencing. The pattern of responses of these cells to androgen was compared to that of MOP cells and that of JAC cells established from LNCaP-like MOP cells. R1881, a synthetic androgen: (1) repressed the growth of all the six ME cell lines obtained, MOP and JAC cells, (2) augmented the secretion of PSA, (3) induced spectacular cell bubbling/fragmentation and (4) blocked the cell cycle and induced a modest increase of apoptosis. All the androgen-repressed cells expressed the same level of mutated AR as LNCaP cells. In nude mice, the growth of ME-2 cell xenografts displayed transient androgen repression similar to that of MOP cells. In culture neither fibroblasts nor extra-cellular matrix altered the effects of R1881 on cell proliferation. These results demonstrate that androgen-independent tumors contain androgen-responsive cells. The apparent discrepancy between the responses to androgen of tumors and those of carcinoma cells in culture suggests that microenvironmental factors contribute to the androgen responsiveness of tumor cells in vivo. These modifications, albeit unspecified, could be suitable targets for restoring the androgen responsiveness of AI tumors.

Introduction Des modeles animaux transgeniques suggerent que la prevalence des tumeurs thyroidiennes pourrait etre augmentee au cours de la Neoplasie Endocrinienne Multiple de type1 (NEM1). Les donnees de la litterature chez l’homme sont discordantes. Neanmoins, des mutations somatiques de menine ont ete retrouvees, recemment dans un sous-groupe de cancers thyroidiens oncocytaires. Objectifs Analyser l’expression de la menine dans differents types de tumeurs thyroidiennes. Materiels et methodes 47 echantillons de tissus thyroidiens (12 carcinomes papillaires (CP), 5 carcinomes anaplasiques (CA), 12 carcinomes peu differencies (CPD), 5 carcinomes medullaires (CM), 5 carcinomes oncocytaires (CO), 3 adenomes oncocytaires (AO) et 5 goitres (B), ont ete testes par immunohistochimie avec un anticorps anti-menine. L’expression semi-quantitative de la menine a ete evaluee dans les noyaux des cellules thyroidiennes comme positive (+, ++, ++ + ), faible (±) ou negative. Resultats L’expression de la menine est positive, comparable a celle du tissu sain dans 38 cas (81 %). Elle est, par contre faible ( n = 8) ou absente ( n = 1) dans 9 cas (2 CP, 5 CPD, 2 CO) (19 %) correspondant a 42 % (5/12) des CPD et 40 % des CO (2/5). Conclusion Nos donnees suggerent que l’expression de la menine est le plus souvent conservee dans les tumeurs thyroidiennes mais peut etre absente dans des formes peu differencies ou oncocytaires. Des etudes complementaires sont necessaires pour apprecier la fonction potentielle de la menine dans la carcinogenese thyroidienne.

Background. Insulin-like growth factor-I (IGF-I) bioactivity has been reported to be decreased in maintenance haemodialysis patients and this may affect their nutritional status. Clearances of IGF-I and its binding proteins (IGFBPs) during haemodialysis sessions using a high permeability biocompatible membrane are unknown. Methods. Five well nourished, non-diabetic adult patients were studied during one 4-h morning haemodialysis treatment using the high permeability biocompatible AN-69 dialyser. Blood was collected at the arterial and venous ports of the dialyser at 0, 1, 2 and 4 h of dialysis for haematocrit, plasma IGF-I, IGFBP-3 and insulin measurements. IGF-I, IGFBP-3 and insulin concentrations were adjusted for haemoconcentration before comparisons were made. Results. At the beginning of the dialysis session, plasma IGF-I, IGFBP-3 and insulin levels were within the normal range (297±47 ng/ml (mean±SEM), 4.3±0.6 μg/ml and 11.8±3.4 μIU/ml, respectively). During the session, insulin tended to be cleared through the dialyser, whereas plasma IGF-I and IGFBP-3 values did not vary significantly. Conclusion. Dialysis with the high permeability AN69 membrane did not alter the main blood compounds of the IGF system in well nourished chronic haemodialysis patients, and it is unlikely that the malnutrition frequently observed in such patients would result from alterations of the IGF system during haemodialysis.

Here are described the effects of androgens, and other molecules known to bind to androgen receptors (AR), on MOP cells established from the human prostate cancer cell line LNCaP. MOP cells contained AR: 100000 binding sites/cell, K(D) for 5alpha dihydrotestosterone (DHT) 0.5 nM, size 110 kDa. The AR gene has the same repetition polymorphism in exon 1 and the T876A mutation in exon 8 as LNCaP. The proliferation of MOP cells in culture was repressed by the synthetic androgen 17beta-hydroxy-17-methyl-estra-4,9,11-trien-3-one (R 1881), the antiandrogen cyproterone acetate (CYPA), estradiol (E2), progesterone and the synthetic progestin promegestone: 17,21 dimethyl-19 nor-4,9 pregnandiene-3,20 dione (R 5020). The number of cells recovered after 7 days decreased to approximately 40% of controls. ED(70)s ranged between 50 pM for R 1881 to 50 nM for E2 and CYPA. Treatment with R 1881 decreased [3H]thymidine incorporation into DNA and increased dramatically the doubling time. R 1881, CYPA and E2 blocked the cell cycle between G1 and S phases and they induced apototosis as demonstrated by the increase of blebs on the plasma membrane, nuclear fragmentation, TdT-mediated dUTP nick end-labeling (TUNEL)-positive cells and internucleosomal DNA breaks. In athymic nude mice, testosterone enanthate prevented the growth of MOP tumors and, when tumors did develop, brought about regression. However, the tumors did not regress completely and finally escaped treatment. In conclusion, a variant of the LNCaP cell line has been established. With these cells it was possible to confirm that androgens paradoxically repress the growth of some prostate cancer cells both in culture and in vivo. In addition it is demonstrated in culture but not in vivo, for the first time to the authors' knowledge, that a synthetic androgen is able to induce apoptosis of cells established from human prostate carcinoma.

Acute leptin regulation in end-stage renal failure: The role of growth hormone and IGF-1. Background Leptin, a recently discovered peptide involved in nutrient intake and energy expenditure, has been shown to be abnormally regulated in certain conditions such as obesity. In chronic renal failure, leptin appears to be increased. However, little is known about leptin regulation during chronic renal failure (CRF). Methods We measured serum leptin in eight well nourished, chronic hemodialysis patients (seven males, one female) receiving anabolic factors for three days as either recombinant insulin-like growth factor-1 (rhIGF-1) or a combination of recombinant growth hormone (rhGH) plus recombinant IGF-1, in a random cross-over trial. Results Serum leptin values were in the range of normal volunteers matched for body mass index. As reported in other conditions, serum leptin was strongly correlated with patients dry body wt ( P = 0.01) and body fat ( P = 0.0001). Both treatments affected serum leptin in a rapid and opposite manner. RhIGF-1 decreased serum leptin from 11.2 ± 20.8 (sd) to 4.3 ± 3.8 μg/liter ( P = 0.011), whereas the combination of rhGH + rhIGF-1 increased serum leptin from 7.4 ± 9.4 to 21.0 ± 32.9 μg/liter ( P = 0.011). Regression analyses indicated a linear regression between serum leptin and insulin variations after treatment. Conclusions This study shows for the first time that both rhIGF-1 and rhGH acutely regulate serum leptin in dialysis patients. Whether leptin changes are explained by the concomitant insulin variation should be further studied under renal failure conditions.

Serum interleukin-6 (IL-6) levels were measured in 58 adult patients with newly diagnosed acute myelogenous leukemia (AML) using an ELISA method in order to find potential clinical correlations. Detectable average levels were 57 +/- 68 pg/ml and 52 patients (90%) had higher cytokine levels than normal donors. IL-6 levels (115 +/- 102 pg/ml versus 36 +/- 40 pg/ml, p = 0.0001) were higher in patients with fever of apparently non infectious origin, and higher levels were associated with higher percentage of blasts in the peripheral blood (R = 0.29, p = 0.04) and in the bone marrow (R = 0.39, p = 0.003), elevated serum LDH level (R = 0.36, p = 0.01), hyperbilirubinemia (R = 0.36, p = 0.008), elevated serum GGT level (R = 0.46, p = 0.003), and elevated serum GOT (R = 0.36, p = 0.008) and GPT levels (R = 0.44, p = 0.004). Highest IL-6 levels were observed in FAB M1 (86 +/- 112 pg/ml), M3 (73 +/- 69 pg/ml), and M6 (92 +/- 60 pg/ml) AML subtypes. Serum IL-6 levels in AML might be related to both non specific inflammatory reactions and the specific biology of the disease.

Plasma hPRL consists of a complex mixture of molecular forms. The monomeric form, derived from the pituitary, is the main form. Others (dimeric or oligomeric) can form de novo in plasma. Recently, BBPRL (big big PRL) has been identified in some cases as an antiPRL autoantibody, but these data require further investigation. The PRL forms are differently recognized by immunoassays (IRMA and RIA) and are a source of inter-assay discrepancy.

according to the Goligher's classification. Results: The operation duration was significantly longer (p

We showed that the proliferation of F4Z2 cells, established from a rat pituitary tumor, was stimulated by L-triiodothyronine (LT3) in the presence of 3 or 0.1% charcoal treated-fetal calf serum (CT-FCS), and by estradiol (E2) in the presence of 3% CT-FCS only (Cancer Res., 50, 1990, 3786). Here we report on the consequences of the simultaneous addition of these hormones. In the presence of 0.1% CT-FCS, E2, and with a lower potency, estrone and estriol inhibited dose-dependently stimulation by LT3. The results were more complex with 3% CT-FCS: the LT3 effect was blunted by E2 > 0.1 nM (and vice versa) and the hormone effects were additive at lower concentrations. E2, at concentrations antagonistic to the effects of LT3, decreased LT3 binding and LT3 receptor mRNA without modifying the effect of LT3 on these mRNAs. In addition, E2 blocked both the LT3-induced increases of insulin-like growth factor-I (IGF-I) secretion and IGF-I mRNA concentration, and the LT3-induced decrease of IGF-binding proteins in conditioned culture medium. We propose that E2 prevents LT3 stimulation of F4Z2 cell proliferation by blunting the LT3-induced accumulation of unbound IGF-I in the culture medium.

This paper studies the modulatory effects of two antiestrogens, the steroid ICI 164 384 and the nonsteroidal compound 4-hydroxytamoxifen (4-OH-tam), on the proliferation of L-T3-stimulated cell lines. Three cell lines known to be stimulated by thyroid hormones and to contain estrogen receptors but to have a different estradiol sensitivity to estradiol were used; F4Z2 and MCF-7 cells were stimulated, whereas GH3 cells were insensitive. Cells were counted 6-7 days after hormones and antihormones were added to the culture medium, separately or in association (a fixed hormone concentration and increasing antihormone concentrations and vice versa). In F4Z2 and MCF-7 cells, antiestrogens prevented noncompetitively the stimulatory effect of L-T3 and, as expected, competitively the stimulatory effect of estradiol. In GH3 cells, antiestrogens had proper inhibitory effects, but they did not prevent significantly the proliferative effect of L-T3. To investigate the mechanisms of the modulatory effects in F4Z2 cells we examined the consequences of antiestrogens on thyroid hormone receptors (nuclear binding of L-T3 and mRNAs of thyroid hormone receptors, i.e. c-erbA alpha and -beta) and insulin-like growth factor-I (IGF-I; secretion and mRNAs). Antiestrogens neither competed with L-[125I]T3 nor reproducibly decreased the number and affinity of thyroid hormone-binding sites. While 4-OH-tam frequently decreased the amount of c-erbA beta transcripts, ICI 164 384 did not alter the distribution of alpha and beta cDNA transcripts. Further, neither antiestrogen prevented the increases in IGF-I accumulation in conditioned medium and IGF-I mRNA concentrations induced by L-T3 (0.1 nM). In conclusion, 1) antiestrogens are potent noncompetitive inhibitors of the action of L-T3 on the proliferation of cells whose growth is responsive to estradiol (F4Z2 and MCF-7), but not of the action on a cell line whose growth is insensitive to estradiol (GH3). 2) The loss of L-T3 sensitivity is not due to a loss of thyroid receptors or a decrease in IGF-I production. 3) In addition to estrogen receptors, factors involved in the estradiol control of cell proliferation appear to be required for the antiestrogen inhibition of L-T3 action.

We have shown that growth of F4Z2 cells and F4Z2 tumors was stimulated by estradiol, that of MtTF4 and F4P tumors was inhibited and that of F4P cells remained insensitive. In the present work we explore the possible role of transforming growth factor-beta (TGF-beta) as a mediator of estradiol action in these pituitary tumors and cell lines. In vivo, estradiol treatment increased the concentration of TGF-beta 1 mRNAs in tumors whose growth was inhibited by estradiol (MtTF4 and F4P) but not in tumors whose growth was stimulated (F4Z2). F4Z2 and F4P cell lines also contained TGF-beta 1 transcripts. These cells and tumors differed by two points: the level of TGF-beta 1 transcript was higher in F4Z2 than in F4P cells while the opposite situation was observed in vivo and the concentration of TGF-beta 1 mRNA in cultured cells was insensitive to estradiol (1 or 100 x 10(-9) M). Moreover, the secretion of TGF-beta like activity assayed by two different methods was estradiol insensitive and the growth of both cell lines was dose-dependently inhibited by TGF-beta 1 (ED50:2 x 10(-11) M). Since estradiol increases TGF-beta 1 mRNA in the tumors MtTF4 and F4P whose growth is inhibited by estradiol and that TGF-beta 1 inhibits the proliferation of F4P cells it is proposed as a working hypothesis that TGF-beta 1 is one of the mediators of the inhibitory effect of estradiol in pituitary tumors. No data favor the hypothesis that estradiol stimulates pituitary tumor proliferation by decreasing TGF-beta production.

From the MtTF4 tumor of rat pituitary origin we established the F4Z2 cell line whose growth is stimulated by 17 beta-estradiol (E2). Taking E2 actions as references we investigated actions of other effectors on the proliferation, protein, and insulin growth factor-I (IGF-I) secretions of F4F2 cells. Dexamethasone (Dex) and L-T3 were chosen because they have also intracellular receptors and they act in pituitary cells. Cells were cultured in 96-well plates in RPMI 1640 medium supplemented either with charcoal-treated fetal calf serum (CT-FCS) or with BSA and transferrin. Hormones were added at the time of seeding and cells were counted 2-10 days later without renewing the culture medium. The accumulation of immunoreactive IGF-I in conditioned medium was used as an index of IGF-I secretion. For studies on protein secretion, cells were incubated for 24 h with [35S]methionine and labeled proteins were separated by polyacrylamide gel electrophoresis. We found that: 1) L-T3, like E2, stimulated in a dose-dependent and specific manner the proliferation of F4Z2 cells cultured in the presence of 5% CT-FCS; EC50 was: 1 X 10(-11) M and 0.2 X 10(-11) M for L-T3 and E2, respectively. In contrast, L-T3 but not E2 remained active in serum-free medium; 2) Dex was a strong inhibitor of cell proliferation in serum-free medium and in medium supplemented with 5% CT-FCS (EC50: 5 X 10(-9) M). The antiglucocorticoid RU 38 486 prevented this inhibitory effect; 3) when a stimulator (E2 or L-T3) was simultaneously incubated with the inhibitor (Dex) the number of cells depended on the ratio of hormone concentrations. When there was no large excess of one effector this number was intermediary between those counted in the presence of each hormone separately and L-T3 was more potent than E2 in preventing Dex inhibition; 4) Dex, E2, and L-T3 modified the electrophoretic patterns of secreted proteins but there was no evidence for a correlation between these modifications and the inhibition or the stimulation of cell proliferation, and 5) the accumulation of immunoreactive IGF-I was insensitive to E2, increased by L-T3, and markedly decreased by Dex. L-T3 but not E2 prevented the effect of Dex.(ABSTRACT TRUNCATED AT 400 WORDS)

It is known that estradiol, but not progesterone or dihydrotestosterone, slows down the growth of the MtTF 4 tumor. In the present paper, it is shown that: (1) this tumor contains glucocorticoid receptors, (2) its growth is also inhibited by treatment with dexamethasone (Dex), and (3) the growth rate of a cell line and several clones established from the tumor is negatively controlled by Dex 10 −7 M in culture medium containing 10% gelding serum. Unlike estradiol, Dex does not induce cell hypertrophy. This work suggests that the inhibition of the MtTF 4 tumor growth by Dex may be due in part to a direct action on tumor cells and, taking into consideration previous reports, it allows us to forward the hypothesis that both Dex and estradiol inhibit MtTF 4 tumor growth in two different ways.