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1.
Eur J Cancer ; 94: 168-178, 2018 05.
Article in English | MEDLINE | ID: mdl-29571083

ABSTRACT

INTRODUCTION: The European Organisation for Research and Treatment of Cancer (EORTC) 22033-26033 clinical trial (NCT00182819) investigated whether initial temozolomide (TMZ) chemotherapy confers survival advantage compared with radiotherapy (RT) in low-grade glioma (LGG) patients. In this study, we performed gene expression profiling on tissues from this trial to identify markers associated with progression-free survival (PFS) and treatment response. METHODS: Gene expression profiling, performed on 195 samples, was used to assign tumours to one of six intrinsic glioma subtypes (IGSs; molecularly similar tumours as previously defined using unsupervised expression analysis) and to determine the composition of immune infiltrate. DNA copy number changes were determined using OncoScan arrays. RESULTS: We confirm that IGSs are prognostic in the EORTC22033-26033 clinical trial. Specific genetic changes segregate in distinct IGSs: most samples assigned to IGS-9 have IDH-mutations and 1p19q codeletion, samples assigned to IGS-17 have IDH-mutations without 1p19q codeletion and samples assigned to other intrinsic subtypes often are IDH-wildtype. A trend towards benefit from RT was observed for samples assigned to IGS-9 (hazard ratio [HR] for TMZ is 1.90, P = 0.065) but not for samples assigned to IGS-17 (HR 0.87, P = 0.62). We did not identify genes significantly associated with PFS within intrinsic subtypes, although follow-up time is limited. We also show that LGGs and glioblastomas differ in their immune infiltrate, which suggests that LGGs are less amenable to checkpoint inhibitor-type immune therapies. Gene expression analysis also allows identification of relatively rare subtypes. Indeed, one patient with a pilocytic astrocytoma was identified. CONCLUSION: IGSs are prognostic for PFS in EORTC22033-26033 clinical trial samples.


Subject(s)
Biomarkers, Tumor/genetics , Brain Neoplasms/pathology , Glioma/pathology , Transcriptome , Adult , Aged , Antineoplastic Agents, Alkylating/therapeutic use , Brain Neoplasms/genetics , Brain Neoplasms/therapy , Female , Glioma/genetics , Glioma/therapy , Humans , Male , Middle Aged , Prognosis , Progression-Free Survival , Temozolomide/therapeutic use , Treatment Outcome
2.
Neuro Oncol ; 12(12): 1318-25, 2010 Dec.
Article in English | MEDLINE | ID: mdl-20716594

ABSTRACT

Over the last two decades, chemotherapy has been introduced in protocols for patients with intracranial germinoma with the objective of reducing the volume and the dose of irradiation without compromising survival rates. The aim of this work is to critically analyze the pattern of relapse in a cohort of patients with nonmetastatic germinoma prospectively treated with chemotherapy followed by focal field radiation. Data of all germinoma patients registered in the French protocol for intracranial germ cell tumors between 1990 and 1999 were reviewed. The pattern of relapse, management, and outcome were analyzed in 10 of 60 patients who developed a recurrence after initial treatment. In 9 patients, the site of recurrence was local or loco-regional, notably in the periventricular area for 8. One patient only had isolated distant leptomeningeal relapse. The review of the sites of relapse suggests that most recurrences could have been avoided with a larger ventricular field of radiation. Treatment at first relapse included chemotherapy (10 patients), high-dose chemotherapy and stem cell transplant (8 patients), and/or radiation therapy (4 patients). Five patients experienced a second relapse. At a median follow-up of 72 months since the first relapse, 8 patients are alive in second or third remission. This review identified an excess of periventricular relapses when the focal field of radiation is used in the combined management of germinoma. These relapses are predominantly marginal or outside radiation fields. Ventricular field radiation appears a logical alternative to decrease the incidence of such relapses. Future trials should aim at better identifying patients who may benefit from local and ventricular radiation, respectively.


Subject(s)
Brain Neoplasms/therapy , Germinoma/therapy , Neoplasm Recurrence, Local/therapy , Neoplasms, Germ Cell and Embryonal/therapy , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Brain Neoplasms/pathology , Carboplatin/administration & dosage , Case-Control Studies , Child , Child, Preschool , Cohort Studies , Combined Modality Therapy , Etoposide/administration & dosage , Female , Follow-Up Studies , Germinoma/pathology , Humans , Ifosfamide/administration & dosage , Male , Neoplasm Recurrence, Local/pathology , Neoplasms, Germ Cell and Embryonal/pathology , Prospective Studies , Radiotherapy Dosage , Survival Rate , Treatment Outcome
3.
Cancer Radiother ; 12(5): 352-9, 2008 Sep.
Article in French | MEDLINE | ID: mdl-18511325

ABSTRACT

Merkel cell carcinoma (MCC) are rare neuroendocrine malignant tumor of the skin, occurring in elderly patients. It affects primarily the sun-exposed areas of the skin, with approximately 50% of all tumors occurring in the face and neck and 40% in the extremities. Immunohistochemical markers (CK20+, CK7- and TTF1-) are used to distinguish between MCC and other tumors. MCC have a tendency to rapid local progression, frequent spread to regional lymph nodes and distant metastases. Due to the rarity of the disease, the optimal treatment has not been fully defined. Localized stages (stages I and II) are treated by surgical excision of the primary tumor (with 2 to 3 cm margin) and lymphadenectomy in case of node-positive disease, followed by external beam radiotherapy (EBRT) to a total dose of 50 to 60Gy in the tumor bed. Adjuvant EBRT has been shown to decrease markedly locoregional recurrences and to increase survival in recent studies. Treatment of lymph nodes area is more controversial. Chemotherapy is recommended only for metastatic disease.


Subject(s)
Carcinoma, Merkel Cell/radiotherapy , Skin Neoplasms/radiotherapy , Carcinoma, Merkel Cell/pathology , Carcinoma, Merkel Cell/therapy , Female , Humans , Male , Middle Aged , Prognosis , Skin Neoplasms/pathology , Skin Neoplasms/therapy , Treatment Outcome
4.
J Chem Phys ; 124(11): 114703, 2006 Mar 21.
Article in English | MEDLINE | ID: mdl-16555906

ABSTRACT

Using nozzle beams of He, Ne, and Ar, we have measured diffractive selective adsorption resonances from a Cu(110) surface kept at 20 K. Bound state energies of the atom-surface potentials have been determined from plots of the measured resonance energies versus incident angle and their fits to calculated kinematical dispersion relations. For 3He and 4He we have found a unique level assignment that is compatible with a single gas-surface potential curve with a well depth of 6.05 meV of the He-Cu(110) potential. This value is about 10% larger than the prediction of 5.55 meV from the current physisorption theory. The Ne and Ar data reveal a large number of closely spaced levels with level separations and estimated van der Waals coefficients that are compatible with available theoretical data.

5.
Nucleic Acids Res ; 34(Database issue): D68-73, 2006 Jan 01.
Article in English | MEDLINE | ID: mdl-16381958

ABSTRACT

We describe cisRED, a database for conserved regulatory elements that are identified and ranked by a genome-scale computational system (www.cisred.org). The database and high-throughput predictive pipeline are designed to address diverse target genomes in the context of rapidly evolving data resources and tools. Motifs are predicted in promoter regions using multiple discovery methods applied to sequence sets that include corresponding sequence regions from vertebrates. We estimate motif significance by applying discovery and post-processing methods to randomized sequence sets that are adaptively derived from target sequence sets, retain motifs with p-values below a threshold and identify groups of similar motifs and co-occurring motif patterns. The database offers information on atomic motifs, motif groups and patterns. It is web-accessible, and can be queried directly, downloaded or installed locally.


Subject(s)
Computational Biology , Databases, Nucleic Acid , Genomics , Response Elements , Animals , Internet , Promoter Regions, Genetic , User-Computer Interface
6.
Lancet ; 366(9490): 985-90, 2005.
Article in English | MEDLINE | ID: mdl-16168780

ABSTRACT

BACKGROUND: Postoperative policies of "wait-and-see" and radiotherapy for low-grade glioma are poorly defined. A trial in the mid 1980s established the radiation dose. In 1986 the EORTC Radiotherapy and Brain Tumor Groups initiated a prospective trial to compare early radiotherapy with delayed radiotherapy. An interim analysis has been reported. We now present the long-term results. METHODS: After surgery, patients from 24 centres across Europe were randomly assigned to either early radiotherapy of 54 Gy in fractions of 1.8 Gy or deferred radiotherapy until the time of progression (control group). Patients with low-grade astrocytoma, oligodendroglioma, mixed oligoastrocytoma, and incompletely resected pilocytic astrocytoma, with a WHO performance status 0-2 were eligible. Analysis was by intention to treat, and primary endpoints were overall and progression-free survival. FINDINGS: 157 patients were assigned early radiotherapy, and 157 control. Median progression-free survival was 5.3 years in the early radiotherapy group and 3.4 years in the control group (hazard ratio 0.59, 95% CI 0.45-0.77; p<0.0001). However, overall survival was similar between groups: median survival in the radiotherapy group was 7.4 years compared with 7.2 years in the control group (hazard ratio 0.97, 95% CI 0.71-1.34; p=0.872). In the control group, 65% of patients received radiotherapy at progression. At 1 year, seizures were better controlled in the early radiotherapy group. INTERPRETATION: Early radiotherapy after surgery lengthens the period without progression but does not affect overall survival. Because quality of life was not studied, it is not known whether time to progression reflects clinical deterioration. Radiotherapy could be deferred for patients with low-grade glioma who are in a good condition, provided they are carefully monitored.


Subject(s)
Astrocytoma/radiotherapy , Central Nervous System Neoplasms/radiotherapy , Oligodendroglioma/radiotherapy , Adolescent , Adult , Aged , Astrocytoma/mortality , Central Nervous System Neoplasms/mortality , Disease Progression , Disease-Free Survival , Female , Humans , Male , Middle Aged , Oligodendroglioma/mortality , Radiotherapy Dosage , Survival Rate
8.
Int J Radiat Oncol Biol Phys ; 46(4): 959-68, 2000 Mar 01.
Article in English | MEDLINE | ID: mdl-10705018

ABSTRACT

PURPOSE: The aim of this study was to identify factors that could lead to optimization of the management of pineal parenchymal tumors (PPT) which remains equivocal and controversial. METHODS AND MATERIALS: In order to determine factors that influence PPT prognosis, a series of 76 consecutive patients from 12 European centers with histologically proven tumors was retrospectively reviewed. The clinical records and material for histologic review were available in all cases. Follow-up was achieved in 90% of cases. RESULTS: According to WHO classification, there were 19 pineocytomas, 28 intermediate and mixed PPT, and 29 pineoblastomas. According to a four-grade institutional classification, there were 11 Grade 1, 27 Grade 2, 20 Grade 3, and 18 Grade 4. Surgical resection was attempted in 44 patients, whereas 30 had biopsy only. In one case, diagnosis was made at autopsy and in another on spinal deposits. Forty-four patients were irradiated following surgery, 15 patients received chemotherapy. Forty-one patients were alive (median follow-up: 85 months); 9 patients died perioperatively; 26 patients relapsed. Univariate analysis showed a good outcome correlated with age above 20 years, tumor diameter less than 25 mm, and low-grade histology. Multivariate analysis confirmed histology and tumor volume to be significant independent prognostic factors. The extent of surgery and radiotherapy had no clear influence on survival. CONCLUSIONS: This review highlights the prognostic features of PPT and may help to determine treatment strategies based on radiologic and pathologic characteristics.


Subject(s)
Pinealoma/pathology , Pinealoma/therapy , Adolescent , Adult , Aged , Analysis of Variance , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Biopsy , Child , Child, Preschool , Combined Modality Therapy , Female , Follow-Up Studies , Humans , Infant , Male , Middle Aged , Pinealoma/mortality , Prognosis , Radiotherapy/adverse effects , Radiotherapy Dosage , Retrospective Studies
9.
Gastrointest Endosc ; 51(3): 262-5, 2000 Mar.
Article in English | MEDLINE | ID: mdl-10699768

ABSTRACT

BACKGROUND: There is growing advocacy for the use of disposable medical accessories to reduce the risks of infection transmission. Their purchase costs can, however, be considered as prohibitive in an endoscopy unit operating under a cost-containment program. We therefore compared the costs of reusable and disposable biopsy forceps. METHODS: From October 1995 to September 1997, biopsies were obtained in 7740 sessions. The evaluation of costs included purchase prices, repairs, cleaning (chemicals, equipment, technician time) and autoclaving costs in a centralized sterilization unit. For comparison, the lowest purchase price for disposable biopsy forceps was $26.90 in 1997. RESULTS: A mean of 12 new reusable forceps were purchased every year for a total purchase price of $5460. A total of 315 biopsy sessions were performed per forceps (mean time life of 3 years per forceps, including 3 repairs). Yearly repair cost was $3308, equipment $1002, chemicals $3250, central sterilization $8333, and technician salary $4373. Total cost was $25,726 and cost per biopsy session was $6.65. CONCLUSIONS: Total purchase and reprocessing costs for reusable biopsy forceps were 25% of those of disposable devices. The use of disposable biopsy forceps would have led to a yearly extra cost of $78,377 in the operation of our endoscopy unit.


Subject(s)
Biopsy/instrumentation , Disposable Equipment/economics , Surgical Instruments/economics , Belgium , Cost-Benefit Analysis , Costs and Cost Analysis , Endoscopy, Gastrointestinal/economics , Equipment Reuse/economics , Humans , Prospective Studies
10.
Electrophoresis ; 21(18): 3994-4016, 2000 Dec.
Article in English | MEDLINE | ID: mdl-11192120

ABSTRACT

Nonaqueous capillary electrophoresis (NACE) is the application of a conductive electrolyte dissolved in either one organic solvent or a mixture of several organic solvents to carry out zone electrophoresis or related techniques in fused-silica capillaries. A complete review on the fundamentals, the optimization of analytical methods, practical considerations, and applications is given. To explain the differences to CE in aqueous media, a brief summary on solvent properties and molecular interactions in solutions introduces the reader into these fields. The use of additives to tune separation selectivity by means beyond a pure zone-electrophoretic mechanism is discussed in detail for organic media. Special detection techniques providing high potential for NACE are presented. Data on the precision of NACE methods and a list of relevant applications are included. More specialized applications like the determination of physicochemical constants in NACE or the setup of a semipreparative mode are described.


Subject(s)
Electrophoresis, Capillary/methods , Solvents
11.
Bull Cancer ; 86(3): 279-82, 1999 Mar.
Article in French | MEDLINE | ID: mdl-10210761

ABSTRACT

The authors report a case-history of lymphangiosarcoma or Stewart-Treves syndrome which occurred in a patient with posttraumatic lymphedema of the arm. He presented two recurrences after surgery which led to the decision of amputation. He is now disease free nine years after this treatment. Initially defined as "lymphangiosarcoma arising in chronic lymphedematous extremities after mastectomy for breast cancer", Stewart-Treves syndrome complicates rarely traumatic, postsurgical, postradiation, idiopathic, congenital or filarial lymphedema. Clinical diagnosis is based on nodular, purple and frequently multiple skin lesions on chronic lymphedema of the limb. A proliferating malignant endothelium with affinity for anti-factor-VIII is found on histological slides. The tumor aggressivity explains the short survival if no treatment is given. Stewart-Treves syndrome prognosis is poor, with the occurrence of multiple local recurrences and pulmonary metastasis. On account of its rarity, there is no therapeutic consensus. In localized stage, radical surgery is usually performed. Conservative treatment with complete tumour removal and postoperative radiotherapy has not been yet evaluated. In metastatic or locally advanced tumours, it is necessary to study the benefit of cytotoxic drugs like anthacyclins and ifosfamide known to be effective on soft tissue sarcomas.


Subject(s)
Arm Injuries/complications , Fractures, Bone/complications , Hand , Lymphangiosarcoma/etiology , Lymphedema/complications , Amputation, Surgical , Humans , Lymphangiosarcoma/pathology , Lymphangiosarcoma/surgery , Male , Middle Aged , Prognosis , Skin Transplantation , Syndrome
12.
Article in English | MEDLINE | ID: mdl-9669086

ABSTRACT

Regeneration experiments in Hydra have shown that lithium long-term treatment apparently causes a transformation of prospective head into foot tissue. Although lithium ions are known to interfere with the PI-PKC signal-transduction system and evidence has been provided that this system plays a role in pattern formation in Hydra, its role in mediating the lithium effect on patterning is still obscure. The present study provides evidence that H2O2 and presumably also lipid hydroperoxides mediate the lithium effects. First, the perturbation of pattern formation is strikingly stronger in the strain Hydra vulgaris than in Hydra magnipapillata, and similar strain-specific differences are found in the long lasting accumulation of hydroperoxides following lithium treatment. Second, the antioxidant vitamins E and C, which suppress peroxide accumulation, and the H2O2-degrading enzyme catalase significantly protect H. vulgaris from lithium effects. Lithium treatment also negatively affects overall DNA synthesis in a similar strain-specific manner, which, however, cannot be rescued by antioxidant vitamins. The lithium-activated source of peroxide production differs from another source, which generates peroxide in untreated polyps of both strains. The results suggest that lithium treatment-induced peroxide accumulation in H. vulgaris provokes a cytotoxic response showing foot-like characteristics. Nevertheless, a role of peroxides as messengers in pattern forming processes can not be excluded.


Subject(s)
Hydra/physiology , Hydrogen Peroxide/metabolism , Lithium/pharmacology , Regeneration/drug effects , Animals , Antioxidants/pharmacology , Catalase/pharmacology , Cell Differentiation , DNA/biosynthesis , Lipid Peroxides/metabolism , Peroxidase/metabolism , Vitamins/pharmacology
13.
Dev Genes Evol ; 207(8): 489-501, 1998 Feb.
Article in English | MEDLINE | ID: mdl-9510544

ABSTRACT

Two different cDNA clones from Hydra (HvPKC1a and HvPKC1b) were characterized, which encode members of the cPKC family of protein kinase Cs (PKCs). The two predicted proteins differ only in their amino-terminal sequences and thus probably represent the products of alternatively spliced mRNAs from a single gene. In situ hybridization with a probe recognizing sequences in common between the two mRNAs detects HvPKC1 RNA in all parts of the adult polyp except the foot. The mRNA is contained in ecto- and endodermal epithelial cells as well as a certain subset of gland cells and pairs of interstitial cells. During head and foot formation, induced by either regeneration, budding, lithium treatment or repeated application of a diacylglycerol, HvPKC1 expression is upregulated immediately prior to the evagination of tentacles and downregulated by foot formation. Although PKC activity is clearly inducible in vitro by diacylglycerol and a tumour promoting phorbol ester, structural features detected in the regulatory domains of HvPKC1a and 1b indicate that endogenous activators for Hydra PKC might differ from those of other organisms. The results corroborate the hypothesis that signal transduction systems using protein kinase C are key elements controlling the formation of head structures in Hydra.


Subject(s)
Gene Expression Regulation, Developmental , Gene Expression Regulation, Enzymologic , Hydra/embryology , Hydra/genetics , Protein Kinase C/genetics , Amino Acid Sequence , Animals , Enzyme Activation , Hydra/anatomy & histology , Hydra/drug effects , Hydra/enzymology , Molecular Sequence Data , Protein Kinase C/chemistry , Sequence Homology, Amino Acid , Signal Transduction , Subcellular Fractions , Tetradecanoylphorbol Acetate/pharmacology , Up-Regulation
14.
Dev Genes Evol ; 207(8): 502-14, 1998 Feb.
Article in English | MEDLINE | ID: mdl-9510545

ABSTRACT

Several studies have provided strong, but indirect evidence that signalling through pathways involving protein kinase C (PKC) plays an important role in morphogenesis and patterning in Hydra. We have cloned a gene (HvPKC2) from Hydra vulgaris which encodes a member of the nPKC subfamily. In adult polyps, HvPKC2 is expressed at high levels in two locations, the endoderm of the foot and the endoderm of the hypostomal tip. Increased expression of HvPKC2 is an early event during head and foot regeneration, with the rise in expression being restricted to the endodermal cells underlying the regenerating ends. No upregulation is observed if regenerates are cut too close to the head to form a foot. Elevated expression of HvPKC2 is also observed in the endoderm underlying lithium-induced ectopic feet. A dynamic and complex pattern of expression is seen in developing buds. Regeneration of either head or foot is accompanied by an increase in the amount of PKC in both soluble and particulate fractions. An increase in the fraction of PKC activity which is membrane-bound is specifically associated with head regeneration. Taken together these data suggest that patterning of the head and foot in Hydra is controlled in part by the level of HvPKC2 expression, whilst head formation is accompanied by an in vivo activation of both calcium-dependent and independent PKC isoforms.


Subject(s)
Body Patterning/physiology , Hydra/enzymology , Protein Kinase C/genetics , Animals , Body Patterning/genetics , Gene Expression Regulation, Developmental , Gene Expression Regulation, Enzymologic , Humans , Hydra/anatomy & histology , Hydra/embryology , Hydra/genetics , Phylogeny , Protein Kinase C/classification , RNA/metabolism , Regeneration , Up-Regulation
15.
Hum Mol Genet ; 6(8): 1383-7, 1997 Aug.
Article in English | MEDLINE | ID: mdl-9259288

ABSTRACT

Cowden disease, also known as multiple hamartoma syndrome, is an autosomal dominant cancer syndrome with a high risk of breast and thyroid cancer. The gene involved has been localized to chromosome 10q22-23. Recently, the tumour suppressor gene PTEN/MMAC1, encoding a putative protein tyrosine or dual-specificity phosphatase, was cloned from that region and three mutations were detected in patients with Cowden disease. We confirmed that the PTEN/MMAC1 gene is indeed the gene for Cowden disease by a refined localization of the gene to the interval between D10S1761 and D10S541, which contains the PTEN/MMAC1 gene and, by mutation analysis in eight unrelated familial and 11 sporadic patients with Cowden disease. Eight different mutations were detected in various regions of the PTEN/MMAC1 gene. One mutation was detected twice. All detected changes in the gene can be predicted to have a very deleterious effect on the putative protein. Five of the nine patients have a mutation in exon 5 coding for the putative active site and flanking amino acids. Evaluation of the clinical data of the patients in which a mutation could be detected gives no clear indications for a correlation between the genotype and phenotype. In 10 patients no mutation could be detected so far. In support of the linkage data, no evidence has emerged from the phenotype of these patients suggestive for genetic heterogeneity.


Subject(s)
Chromosomes, Human, Pair 10 , Genes, Tumor Suppressor , Germ-Line Mutation , Hamartoma Syndrome, Multiple/genetics , Phosphoric Monoester Hydrolases , Protein Tyrosine Phosphatases/genetics , Tumor Suppressor Proteins , Adult , Chromosome Mapping , DNA Mutational Analysis , Female , Humans , Male , PTEN Phosphohydrolase , Pedigree
16.
Dev Genes Evol ; 206(7): 435-446, 1997 Mar.
Article in English | MEDLINE | ID: mdl-27747386

ABSTRACT

A gene encoding a member of the growing family of regulatory WD-repeat proteins has been identified in Hydra vulgaris. About 80% of its deduced amino acids are identical to RACK1, which has recently been identified in rat as a receptor for activated C kinase. The presence of a consensus sequence believed to be important for interaction with protein kinase C, prompted us to term the new sequence HvRACK1 (Hydra vulgaris RACK1). In situ hybridization revealed an abundant message restricted to 80% of the body column with the strongest signal in the upper body half. Terminally differentiated structures (foot, tentacles and apicalmost hypostomal cells) were completely free of expression. A corresponding prepattern was established in bisected animals at least 10 h before the regenerating structure began to form. In normal animals HvRACK1 transcripts were contained mainly in interstitial cells (i-cells), gland cells and digestive epithelial cells. Depletion of i-cells and their derivatives by hydroxyurea (HU) treatment induced expression of the gene in epithelio-muscular and -digestive cells with the overall expression level remaining stable as confirmed by northern blotting. Polyps consisting almost exclusively of epithelial cells expressed HvRACK1 differentially along the body axis with a maximum in the head (except tentacles and the apicalmost ectoderm of the hypostome) and fading out towards the foot. The enhanced expression level in epithelial cells of HU-treated animals indicates that these might take over regionspecific HvRACK1 functions usually inherent to interstitial cells and certain derivatives of this lineage.

18.
Dev Biol ; 177(2): 439-48, 1996 Aug 01.
Article in English | MEDLINE | ID: mdl-8806822

ABSTRACT

Lithium ions affect pattern formation in the freshwater polyp Hydra vulgaris in a complex manner. Although a long-term treatment with 1 mM LiCl completely suppresses both head formation and budding, a reduction of the lithium concentration during a long-term treatment from 4 to 1 mM LiCl strongly promotes the differentiation of ectopic head structures. Meanwhile, budding, often interpreted as a special case of head formation, remains suppressed. The appearance of ectopic tentacles under these conditions is surprising as they develop while the animals remain in the presence of 1 mM LiCl, a concentration which would normally suppress the formation of tentacles. On a molecular level, the induction of ectopic head structures by the shift in the LiCl concentration is preceded by an increase in the level of inositol phosphates, indicating an activation of the phosphatidylinositol (PI) cycle. Increased inositol phosphate levels persist for at least 24 hr. Our results provide evidence that (i) tentacle- and bud-forming systems need different and possibly mutually exclusive physiological preconditions and (ii) prolonged inhibition of the PI cycle after initial activation might be necessary to obtain ectopic tentacles.


Subject(s)
Head/embryology , Hydra/embryology , Lithium/pharmacology , Phosphatidylinositols/metabolism , Animals , Cell Differentiation/drug effects , Cell Differentiation/physiology , Dose-Response Relationship, Drug , Hydra/drug effects , Inositol Phosphates/analysis , Morphogenesis/drug effects
19.
Int J Dev Biol ; 40(1): 323-30, 1996 Feb.
Article in English | MEDLINE | ID: mdl-8735944

ABSTRACT

Pattern control in Hydra has traditionally been assigned to the determining influence of morphogens and neuropeptides. However, at present, arachidonic acid and its derivative 12-S-HETE are the only identified, potential signal molecules known to promote head and bud formation. More potent factors might exist but are not yet identified. Nonetheless, it is possible to evoke the development of an almost unlimited number of supernumerary head structures and to induce ectopic foot formation by interference with the PI-PKC signal transducing system. Such an interference can also rescue the regeneration-deficient mutant reg-16. Regarding signals in the development of Hydractinia, metamorphosis is induced by an external key stimulus, i.e. a lipid derived from environmental bacteria. The reception of this stimulus involves PKC-mediated responses. Upon its reception, a neuropeptide is released as an internal, synchronising signal. Members of the novel LWamide family of peptides appear to represent this internal signal. In postmetamorphic development, a glycoprotein SIF serves as an inducer of stolon formation.


Subject(s)
Cnidaria/growth & development , Cnidaria/metabolism , Hydra/growth & development , Hydra/metabolism , Protein Sorting Signals/metabolism , Animals , Cnidaria/genetics , Hydra/genetics , Metamorphosis, Biological , Models, Biological , Mutation , Neuropeptides/metabolism , Regeneration/genetics , Signal Transduction
20.
Am J Gastroenterol ; 90(7): 1162-4, 1995 Jul.
Article in English | MEDLINE | ID: mdl-7611219

ABSTRACT

We report herein three cases of hepatocellular carcinoma revealed by bone metastases. The metastases were located in the skull, the iliac bone, and the femur. The metastases were treated by radiotherapy, and/or surgery. With regard to the liver malignancy itself, two patients were treated by tamoxifen and one by chemoembolizations. Two patients are alive 27 and 31 months after the first sign, and one died 31 months after the diagnosis. In conclusion, in patients with hepatocellular carcinoma revealed by bone metastases, long survival was obtainable in a few cases, and aggressive treatment could be of interest.


Subject(s)
Bone Neoplasms/secondary , Carcinoma, Hepatocellular/diagnosis , Liver Neoplasms/diagnosis , Aged , Bone Neoplasms/therapy , Carcinoma, Hepatocellular/therapy , Embolization, Therapeutic , Female , Humans , Liver Neoplasms/therapy , Male , Middle Aged , Tamoxifen/therapeutic use
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