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1.
Endocr Relat Cancer ; 27(6): R145-R161, 2020 06.
Article in English | MEDLINE | ID: mdl-32229700

ABSTRACT

Metastatic duodenopancreatic neuro-endocrine tumors (dpNETs) are the most important disease-related cause of death in patients with multiple endocrine neoplasia type 1 (MEN1). Nonfunctioning pNETs (NF-pNETs) are highly prevalent in MEN1 and clinically heterogeneous. Therefore, management is controversial. Data on prognostic factors for risk stratification are limited. This systematic review aims to establish the current state of evidence regarding prognostic factors in MEN1-related NF-pNETs. We systematically searched four databases for studies assessing prognostic value of any factor on NF-pNET progression, development of distant metastases, and/or overall survival. In- and exclusion, critical appraisal and data-extraction were performed independently by two authors according to pre-defined criteria. Thirteen studies (370 unique patients) were included. Prognostic factors investigated were tumor size, timing of surgical resection, WHO grade, methylation, p27/p18 expression by immunohistochemistry (IHC), ARX/PDX1 IHC and alternative lengthening of telomeres. Results were complemented with evidence from studies in MEN1-related pNET for which data could not be separately extracted for NF-pNET and data from sporadic NF-pNET. We found that the most important prognostic factors used in clinical decision making in MEN1-related NF-pNETs are tumor size and grade. NF-pNETs <2 cm may be managed with watchful waiting, while surgical resection is advised for NF-pNETs ≥2 cm. Grade 2 NF-pNETs should be considered high risk. The most promising and MEN1-relevant avenues of prognostic research are multi-analyte circulating biomarkers, tissue-based molecular factors and imaging-based prognostication. Multi-institutional collaboration between clinical, translation and basic scientists with uniform data and biospecimen collection in prospective cohorts should advance the field.


Subject(s)
Multiple Endocrine Neoplasia Type 1/genetics , Female , Humans , Male , Prognosis , Treatment Outcome
2.
Endocr Relat Cancer ; 27(8): T9-T25, 2020 08.
Article in English | MEDLINE | ID: mdl-32069215

ABSTRACT

The PanNET Working Group of the 16th International Multiple Endocrine Neoplasia Workshop (MEN2019) convened in Houston, TX, USA, 27-29 March 2019 to discuss key unmet clinical needs related to PanNET in the context of MEN1, with a special focus on non-functioning (nf)-PanNETs. The participants represented a broad range of medical scientists as well as representatives from patient organizations, pharmaceutical industry and research societies. In a case-based approach, participants addressed early detection, surveillance, prognostic factors and management of localized and advanced disease. For each topic, after a review of current evidence, key unmet clinical needs and future research directives to make meaningful progress for MEN1 patients with nf-PanNETs were identified. International multi-institutional collaboration is needed for adequately sized studies and validation of findings in independent datasets. Collaboration between basic, translational and clinical scientists is paramount to establishing a translational science approach. In addition, bringing clinicians, scientists and patients together improves the prioritization of research goals, assures a patient-centered approach and maximizes patient involvement. It was concluded that collaboration, research infrastructure, methodologic and reporting rigor are essential to any translational science effort. The highest priority for nf-PanNETs in MEN1 syndrome are (1) the development of a data and biospecimen collection architecture that is uniform across all MEN1 centers, (2) unified strategies for diagnosis and follow-up of incident and prevalent nf-PanNETs, (3) non-invasive detection of individual nf-PanNETs that have an increased risk of metastasis, (4) chemoprevention clinical trials driven by basic research studies and (5) therapeutic targets for advanced disease based on biologically plausible mechanisms.


Subject(s)
Multiple Endocrine Neoplasia Type 1/complications , Pancreatic Neoplasms/etiology , Adult , Female , Humans , Pancreatic Neoplasms/pathology
3.
Br J Surg ; 105(4): 350-357, 2018 03.
Article in English | MEDLINE | ID: mdl-29405252

ABSTRACT

BACKGROUND: Hypoparathyroidism, the most common complication after thyroid surgery, leads to hypocalcaemia and significant medical problems. An RCT was undertaken to determine whether intraoperative parathyroid gland angiography with indocyanine green (ICG) could predict postoperative hypoparathyroidism, and obviate the need for systematic blood tests and oral calcium supplementation. METHODS: Between September 2014 and February 2016, patients who had at least one well perfused parathyroid gland on ICG angiography were randomized to receive standard follow-up (measurement of calcium and parathyroid hormone (PTH) on postoperative day (POD) 1 and systematic supplementation with calcium and vitamin D; control group) or no supplementation and no blood test on POD 1 (intervention group). In all patients, calcium and PTH levels were measured 10-15 days after thyroidectomy. The primary endpoint was hypocalcaemia on POD 10-15. RESULTS: A total of 196 patients underwent ICG angiography during thyroid surgery, of whom 146 had at least one well perfused parathyroid gland on ICG angiography and were randomized. None of these patients presented with hypoparathyroidism, including those who did not receive calcium supplementation. The intervention group was statistically non-inferior to the control group (exact 95 per cent c.i. of the difference in proportion of patients with hypocalcaemia -0·053 to 0·053; P = 0·012). Eleven of the 50 excluded patients, in whom no well perfused parathyroid gland could be identified by angiography, presented with hypoparathyroidism on POD 1, and six on POD 10-15, which was significantly different from the findings in randomized patients (P = 0·007). CONCLUSION: ICG angiography reliably predicts the vascularization of the parathyroid glands and obviates the need for postoperative measurement of calcium and PTH, and supplementation with calcium in patients with at least one well perfused parathyroid gland. Registration number: NCT02249780 (http://www.clinicaltrials.gov).


Subject(s)
Hypoparathyroidism/diagnosis , Indocyanine Green , Intraoperative Care/methods , Optical Imaging , Parathyroid Glands/diagnostic imaging , Postoperative Complications/diagnosis , Thyroidectomy , Adult , Aged , Female , Fluorescent Dyes , Follow-Up Studies , Humans , Hypoparathyroidism/etiology , Male , Middle Aged , Prospective Studies
4.
Endocr Relat Cancer ; 24(10): T243-T260, 2017 10.
Article in English | MEDLINE | ID: mdl-28811298

ABSTRACT

Multiple endocrine neoplasia type 1 (MEN1) is a hereditary autosomal dominant disorder associated with numerous neuroendocrine tumors (NETs). Recent advances in the management of MEN1 have led to a decrease in mortality due to excess hormones; however, they have also led to an increase in mortality from malignancy, particularly NETs. The main challenges are to localize these tumors, to select those that need therapy because of the risk of aggressive behavior and to select the appropriate therapy associated with minimal morbidity. This must be applied to a hereditary disease with a high risk of recurrence. The overall aim of management in MEN1 is to ensure that the patient remains disease- and symptom-free for as long as possible and maintains a good quality of life. Herein, we review the changes that occurred in the last 20 years in the surgical management of MEN1-associated functional and non-functional pancreatico-duodenal NETs and thymic and bronchial NETs.


Subject(s)
Multiple Endocrine Neoplasia Type 1/surgery , Neuroendocrine Tumors/surgery , Humans , Multiple Endocrine Neoplasia Type 1/pathology , Neuroendocrine Tumors/pathology
5.
Br J Surg ; 103(5): 537-43, 2016 Apr.
Article in English | MEDLINE | ID: mdl-26864909

ABSTRACT

BACKGROUND: Postoperative hypoparathyroidism remains the most common complication following thyroidectomy. The aim of this pilot study was to evaluate the use of intraoperative parathyroid gland angiography in predicting normal parathyroid gland function after thyroid surgery. METHODS: Angiography with the fluorescent dye indocyanine green (ICG) was performed in patients undergoing total thyroidectomy, to visualize vascularization of identified parathyroid glands. RESULTS: Some 36 patients underwent ICG angiography during thyroidectomy. All patients received standard calcium and vitamin D supplementation. At least one well vascularized parathyroid gland was demonstrated by ICG angiography in 30 patients. All 30 patients had parathyroid hormone (PTH) levels in the normal range on postoperative day (POD) 1 and 10, and only one patient exhibited asymptomatic hypocalcaemia on POD 1. Mean(s.d.) PTH and calcium levels in these patients were 3·3(1·4) pmol/l and 2·27(0·10) mmol/l respectively on POD 1, and 4·0(1.6) pmol/l and 2·32(0·08) mmol/l on POD 10. Two of the six patients in whom no well vascularized parathyroid gland could be demonstrated developed transient hypoparathyroidism. None of the 36 patients presented symptomatic hypocalcaemia, and none received treatment for hypoparathyroidism. CONCLUSION: PTH levels on POD 1 were normal in all patients who had at least one well vascularized parathyroid gland demonstrated during surgery by ICG angiography, and none required treatment for hypoparathyroidism.


Subject(s)
Fluorescent Dyes , Hypoparathyroidism/diagnosis , Indocyanine Green , Intraoperative Care/methods , Parathyroid Glands/blood supply , Postoperative Complications/diagnosis , Thyroidectomy , Adult , Aged , Female , Follow-Up Studies , Humans , Hypoparathyroidism/etiology , Male , Middle Aged , Pilot Projects
6.
J Clin Endocrinol Metab ; 101(2): 353-8, 2016 Feb.
Article in English | MEDLINE | ID: mdl-26678657

ABSTRACT

CONTEXT: Germline mutations in the phosphatase and tensin homolog (PTEN) tumor suppressor gene are found in the majority of patients with Cowden syndrome (CS), who have an increased risk of breast, thyroid, and endometrial cancer. According to our current understanding of genetic changes in the PTEN gene and the resultant phenotypic features of CS, pancreatic neuroendocrine tumors (NETs) are not considered part of the clinical spectrum of CS. CASE DESCRIPTION: We report a unique case of an advanced NET of the pancreas in a patient with CS. The germline DNA sequencing confirmed the clinical diagnosis of CS and revealed a PTEN mutation c.697C→T (p.R233*) causing a premature stop codon in exon 7. The tumor DNA sequencing showed no loss of heterozygosity or any copy number changes and no other deleterious genetic alterations, including those commonly mutated in sporadic pancreatic NETs: MEN1, ATRX, DAXX, TP53, and genes involved in the mammalian target of rapamycin pathway. In addition, the high-throughput transcriptome analyzed by RNA-seq did not reveal any missed genetic alterations, aberrant splicing variants, gene fusions, or gene expression alterations. The immunohistochemical staining of the tumor for PTEN revealed an abnormal, uniformly strong cytoplasmic staining of tumor cells with virtually absent nuclear staining. CONCLUSION: The results from genetic testing and histopathological techniques used to confirm CS diagnosis and characterize this unusual tumor tempted us to believe that in this case, the pancreatic NET was not a sporadic malignancy that occurred by coincidence, but rather represented a new entity in the spectrum of malignancies associated with CS.


Subject(s)
Hamartoma Syndrome, Multiple/diagnosis , Neuroendocrine Tumors/diagnosis , Pancreatic Neoplasms/diagnosis , DNA/genetics , Germ-Line Mutation/genetics , Hamartoma Syndrome, Multiple/genetics , Hamartoma Syndrome, Multiple/pathology , High-Throughput Nucleotide Sequencing , Humans , Male , Middle Aged , Neuroendocrine Tumors/genetics , Neuroendocrine Tumors/pathology , PTEN Phosphohydrolase/genetics , Pancreas/pathology , Pancreatic Neoplasms/genetics , Pancreatic Neoplasms/pathology , Pedigree , RNA, Neoplasm/genetics
7.
Rev Med Suisse ; 8(346): 1321-5, 2012 Jun 20.
Article in French | MEDLINE | ID: mdl-22792596

ABSTRACT

The prevalence of thyroid cancer is steadily rising and the fortuitous discovery of a thyroid nodule is a frequent situation for the clinician. The clinical importance is the need to exclude thyroid cancer. In this article we present the initial work up and treatment options for differentiated thyroid cancer. Initial diagnosis is done with a dosage of thyroid stimulating hormone and a fine needle aspiration guided by ultrasonography, which permits classification of the lesion and guides the choice of treatment.


Subject(s)
Carcinoma/therapy , Thyroid Neoplasms/therapy , Algorithms , Biopsy, Fine-Needle/methods , Carcinoma/classification , Carcinoma/diagnosis , Carcinoma/pathology , Cell Differentiation/physiology , Choice Behavior/physiology , Diagnosis, Differential , Humans , Models, Biological , Thyroid Neoplasms/classification , Thyroid Neoplasms/diagnosis , Thyroid Neoplasms/pathology , Thyroidectomy/methods , Thyroidectomy/statistics & numerical data , Ultrasonography, Interventional
8.
J Med Genet ; 43(8): 641-52, 2006 Aug.
Article in English | MEDLINE | ID: mdl-16473856

ABSTRACT

INTRODUCTION: Epidermolysis bullosa (EB), a group of autosomal heritable blistering diseases, is characterised by extensive phenotypic variability with considerable morbidity and mortality. EB is classified into distinct subtypes depending on the location of blistering within the cutaneous dermoepidermal basement membrane zone. Ten genes are known to harbour mutations in the major types of EB, and the level of expression of these genes within the cutaneous basement membrane zone and in extracutaneous tissues, as well as the types and combinations of the mutations, explain in general terms the phenotypic variability. METHODS: The DebRA Molecular Diagnostics Laboratory, established in 1996 and supported in part by the patient advocacy organisation DebRA of America, has analysed over 1000 families with different forms of EB. RESULTS: In total, 265 cases were submitted with the preliminary diagnosis of junctional or hemidesmosomal forms of EB. We found 393 mutant alleles in seven different genes, with 173 of the mutations being distinct and 71 previously unpublished. DISCUSSION: These findings attest to the clinical and molecular heterogeneity of the junctional and hemidesmosomal subtypes of EB. The results also reveal exceptions to the general rules on genotype-phenotype correlations, unusual phenotypes, and surprising genetics. Collectively, mutation analysis in different forms of EB provides the basis for improved classification with prognostic implications and for prenatal and preimplantation diagnosis in families at risk for recurrence of EB.


Subject(s)
Epidermolysis Bullosa, Junctional/genetics , Hemidesmosomes/genetics , Mutation/genetics , Basement Membrane/cytology , Cell Adhesion Molecules/genetics , DNA Mutational Analysis , Humans , Kalinin
9.
J Med Chem ; 44(24): 4296-9, 2001 Nov 22.
Article in English | MEDLINE | ID: mdl-11708932

ABSTRACT

1-(5-[[(2R,3S)-2-([(1R)-1-[3,5-Bis(trifluoromethyl)phenyl]ethyl]oxy)-3-(4-fluorophenyl)morpholin-4-yl]methyl]-2H-1,2,3-triazol-4-yl)-N,N-dimethylmethanamine hydrochloride 3 is a high affinity, orally active, h-NK(1) receptor antagonist with a long central duration of action and a solubility in water of >100 mg/mL. The construction of the 5-dimethylaminomethyl 1,2,3-triazol-4-yl unit, which incorporates the solubilizing group of 3, was accomplished by thermal rearrangement of a propargylic azide in the presence of dimethylamine. Compound 3 is highly effective in pre-clinical tests that are relevant to clinical efficacy in emesis and depression.


Subject(s)
Antidepressive Agents/chemical synthesis , Antiemetics/chemical synthesis , Morpholines/chemical synthesis , Neurokinin-1 Receptor Antagonists , Triazoles/chemical synthesis , Administration, Oral , Amines/chemical synthesis , Amines/chemistry , Amines/pharmacology , Animals , Animals, Newborn , Antidepressive Agents/chemistry , Antidepressive Agents/pharmacology , Antiemetics/chemistry , Antiemetics/pharmacology , Brain/drug effects , Brain/metabolism , Dogs , Ferrets , Gerbillinae , Guinea Pigs , In Vitro Techniques , Injections, Intravenous , Macaca mulatta , Morpholines/chemistry , Morpholines/pharmacology , Radioligand Assay , Rats , Solubility , Structure-Activity Relationship , Triazoles/chemistry , Triazoles/pharmacology , Vocalization, Animal/drug effects
10.
Biochemistry ; 40(31): 9379-86, 2001 Aug 07.
Article in English | MEDLINE | ID: mdl-11478907

ABSTRACT

Human melanin-concentrating hormone (hMCH) is a potent but nonselective agonist at human melanin-concentrating hormone receptors 1 and 2 (hMCH-1R and hMCH-2R, respectively). To determine the structural features of this neuropeptide which are necessary for efficient binding to and activation of the receptors, Ala-substituted, open-chain, and truncated analogues were synthesized and tested in the binding assays in CHO cells expressing hMCH-1R and hMCH-2R, and in functional assays measuring the level of intracellular calcium mobilization in human HEK-293 cells expressing these receptors. A compound consisting merely of the cyclic core of hMCH with the Arg attached to the N-terminus of the disulfide ring was found to activate both hMCH-1R and hMCH-2R about as effectively as full-length hMCH. Thus, the sequence Arg-cyclo(S-S)(Cys-Met-Leu-Gly-Arg-Val-Tyr-Arg-Pro-Cys) appears to constitute the "active core" that is necessary for agonist potency at hMCH-1R and hMCH-2R. A potent and approximately 4-fold more selective agonist at hMCH-1R than at hMCH-2R is also reported.


Subject(s)
Hypothalamic Hormones/chemistry , Hypothalamic Hormones/physiology , Melanins/chemistry , Melanins/physiology , Peptide Fragments/physiology , Pituitary Hormones/chemistry , Pituitary Hormones/physiology , Receptors, Pituitary Hormone/metabolism , Alanine/metabolism , Amino Acid Sequence , Amino Acid Substitution , Cell Line , Cysteine/metabolism , Disulfides/chemistry , Disulfides/metabolism , Humans , Hypothalamic Hormones/metabolism , Isomerism , Melanins/metabolism , Molecular Sequence Data , Peptide Fragments/chemical synthesis , Peptides, Cyclic/chemical synthesis , Peptides, Cyclic/physiology , Pituitary Hormones/metabolism , Protein Conformation , Receptors, G-Protein-Coupled , Receptors, Pituitary Hormone/agonists
11.
Proc Natl Acad Sci U S A ; 98(13): 7564-9, 2001 Jun 19.
Article in English | MEDLINE | ID: mdl-11404457

ABSTRACT

Melanin-concentrating hormone (MCH) is a 19-aa cyclic neuropeptide originally isolated from chum salmon pituitaries. Besides its effects on the aggregation of melanophores in fish several lines of evidence suggest that in mammals MCH functions as a regulator of energy homeostasis. Recently, several groups reported the identification of an orphan G protein-coupled receptor as a receptor for MCH (MCH-1R). We hereby report the identification of a second human MCH receptor termed MCH-2R, which shares about 38% amino acid identity with MCH-1R. MCH-2R displayed high-affinity MCH binding, resulting in inositol phosphate turnover and release of intracellular calcium in mammalian cells. In contrast to MCH-1R, MCH-2R signaling is not sensitive to pertussis toxin and MCH-2R cannot reduce forskolin-stimulated cAMP production, suggesting an exclusive G(alpha)q coupling of the MCH-2R in cell-based systems. Northern blot and in situ hybridization analysis of human and monkey tissue shows that expression of MCH-2R mRNA is restricted to several regions of the brain, including the arcuate nucleus and the ventral medial hypothalamus, areas implicated in regulation of body weight. In addition, the human MCH-2R gene was mapped to the long arm of chromosome 6 at band 6q16.2-16.3, a region reported to be associated with cytogenetic abnormalities of obese patients. The characterization of a second mammalian G protein-coupled receptor for MCH potentially indicates that the control of energy homeostasis in mammals by the MCH neuropeptide system may be more complex than initially anticipated.


Subject(s)
Brain/metabolism , Chromosomes, Human, Pair 22 , Receptors, Pituitary Hormone/genetics , Receptors, Pituitary Hormone/metabolism , Receptors, Pituitary Hormone/physiology , Amino Acid Sequence , Animals , Base Sequence , CHO Cells , COS Cells , Cell Membrane/physiology , Chlorocebus aethiops , Chromosome Mapping , Cricetinae , Female , Humans , In Situ Hybridization , Male , Molecular Sequence Data , Oncorhynchus keta , Organ Specificity , Pituitary Gland/chemistry , Pituitary Gland/physiology , Radioligand Assay , Receptors, G-Protein-Coupled , Receptors, Pituitary Hormone/chemistry , Recombinant Proteins/metabolism , Sequence Alignment , Sequence Homology, Amino Acid , Transfection
12.
Neuropharmacology ; 39(4): 652-63, 2000 Feb 14.
Article in English | MEDLINE | ID: mdl-10728886

ABSTRACT

The anti-emetic profile of the novel brain penetrant tachykinin NK1 receptor antagonist MK-0869 (L-754,030) 2-(R)-(1-(R)-(3,5-bis(trifluoromethyl)phenylethoxy)-3-(S)-(4-fluor o)phenyl-4-(3-oxo-1,2,4-triazol-5-yl)methylmorpholine and its water soluble prodrug, L-758,298, has been examined against emesis induced by cisplatin in ferrets. In a 4 h observation period, MK-0869 and L-758,298 (3 mg/kg i.v. or p.o.) inhibited the emetic response to cisplatin (10 mg/kg i.v.). The anti-emetic protection afforded by MK-0869 (0.1 mg/kg i.v.) was enhanced by combined treatment with either dexamethasone (20 mg/kg i.v.) or the 5-HT3 receptor antagonist ondansetron (0.1 mg/kg i.v.). In a model of acute and delayed emesis, ferrets were dosed with cisplatin (5 mg/kg i.p.) and the retching and vomiting response recorded for 72 h. Pretreatment with MK-0869 (4-16 mg/kg p.o.) dose-dependently inhibited the emetic response to cisplatin. Once daily treatment with MK-0869 (2 and 4 mg/kg p.o.) completely prevented retching and vomiting in all ferrets tested. Further when daily dosing began at 24 h after cisplatin injection, when the acute phase of emesis had already become established, MK-0869 (4 mg/kg p.o. at 24 and 48 h after cisplatin) prevented retching and vomiting in three out of four ferrets. These data show that MK-0869 and its prodrug, L-758,298, have good activity against cisplatin-induced emesis in ferrets and provided a basis for the clinical testing of these agents for the treatment of emesis associated with cancer chemotherapy.


Subject(s)
Acetals/pharmacology , Antiemetics/pharmacology , Antineoplastic Agents/pharmacology , Cisplatin/toxicity , Morpholines/pharmacology , Neurokinin-1 Receptor Antagonists , Prodrugs/pharmacology , Vomiting/drug therapy , Acute Disease , Animals , Antiemetics/metabolism , Aprepitant , CHO Cells , COS Cells , Cricetinae , Dose-Response Relationship, Drug , Ferrets , Humans , Male , Morpholines/metabolism , Prodrugs/metabolism , Rats , Receptors, Neurokinin-1/metabolism , Solubility
13.
J Med Chem ; 43(6): 1234-41, 2000 Mar 23.
Article in English | MEDLINE | ID: mdl-10737756

ABSTRACT

The regioselective dibenzylphosphorylation of 2 followed by catalytic reduction in the presence of N-methyl-D-glucamine afforded 2-(S)-(1-(R)-(3, 5-bis(trifluoromethyl)phenyl)ethoxy)-3-(S)-(4-fluoro)phenyl-4-(5-(2- phosphoryl-3-oxo-4H,-1,2,4-triazolo)methylmorpholine, bis(N-methyl-D-glucamine) salt, 11. Incubation of 11 in rat, dog, and human plasma and in human hepatic subcellular fractions in vitro indicated that conversion to 2 would be expected to occur in vivo most readily in humans during hepatic circulation. Conversion of 11 to 2 occurred rapidly in vivo in the rat and dog with the levels of 11 being undetectable within 5 min after 1 and 8 mg/kg doses iv in the rat and within 15 min after 0.5, 2, and 32 mg/kg doses iv in the dog. Compound 11 has a 10-fold lower affinity for the human NK-1 receptor as compared to 2, but it is functionally equivalent to 2 in preclinical models of NK-1-mediated inflammation in the guinea pig and cisplatin-induced emesis in the ferret, indicating that 11 acts as a prodrug of 2. Based in part on these data, 11 was identified as a novel, water-soluble prodrug of the clinical candidate 2 suitable for intravenous administration in humans.


Subject(s)
Acetals/chemical synthesis , Acetals/metabolism , Anti-Inflammatory Agents, Non-Steroidal/chemical synthesis , Antiemetics/chemical synthesis , Morpholines/chemical synthesis , Morpholines/metabolism , Neurokinin-1 Receptor Antagonists , Prodrugs/chemical synthesis , Acetals/chemistry , Acetals/pharmacology , Animals , Anti-Inflammatory Agents, Non-Steroidal/chemistry , Anti-Inflammatory Agents, Non-Steroidal/metabolism , Anti-Inflammatory Agents, Non-Steroidal/pharmacology , Antiemetics/chemistry , Antiemetics/metabolism , Antiemetics/pharmacology , Antineoplastic Agents , Aprepitant , Cisplatin , Dogs , Drug Evaluation, Preclinical , Ferrets , Guinea Pigs , Humans , Morpholines/chemistry , Morpholines/pharmacology , Prodrugs/chemistry , Prodrugs/metabolism , Prodrugs/pharmacology , Rats , Solubility , Stereoisomerism , Structure-Activity Relationship , Vomiting/chemically induced , Vomiting/drug therapy , Water
14.
J Biol Chem ; 274(13): 8694-7, 1999 Mar 26.
Article in English | MEDLINE | ID: mdl-10085108

ABSTRACT

We have identified a series of potent, orally bioavailable, non-peptidyl, triarylimidazole and triarylpyrrole glucagon receptor antagonists. 2-(4-Pyridyl)-5-(4-chlorophenyl)-3-(5-bromo-2-propyloxyphenyl)p yrr ole (L-168,049), a prototypical member of this series, inhibits binding of labeled glucagon to the human glucagon receptor with an IC50 = 3. 7 +/- 3.4 nM (n = 7) but does not inhibit binding of labeled glucagon-like peptide to the highly homologous human glucagon-like peptide receptor at concentrations up to 10 microM. The binding affinity of L-168,049 for the human glucagon receptor is decreased 24-fold by the inclusion of divalent cations (5 mM). L-168,049 increases the apparent EC50 for glucagon stimulation of adenylyl cyclase in Chinese hamster ovary cells expressing the human glucagon receptor and decreases the maximal glucagon stimulation observed, with a Kb (concentration of antagonist that shifts the agonist dose-response 2-fold) of 25 nM. These data suggest that L-168,049 is a noncompetitive antagonist of glucagon action. Inclusion of L-168, 049 increases the rate of dissociation of labeled glucagon from the receptor 4-fold, confirming that the compound is a noncompetitive glucagon antagonist. In addition, we have identified two putative transmembrane domain residues, phenylalanine 184 in transmembrane domain 2 and tyrosine 239 in transmembrane domain 3, for which substitution by alanine reduces the affinity of L-168,049 46- and 4. 5-fold, respectively. These mutations do not alter the binding of labeled glucagon, suggesting that the binding sites for glucagon and L-168,049 are distinct.


Subject(s)
Peptides/metabolism , Pyridines/pharmacology , Pyrroles/pharmacology , Receptors, Glucagon/antagonists & inhibitors , Receptors, Glucagon/metabolism , Adenylyl Cyclases/metabolism , Animals , CHO Cells , Cations, Divalent/pharmacology , Cricetinae , Enzyme Activation/drug effects , Glucagon-Like Peptide-1 Receptor , Glucagon-Like Peptides , Hormone Antagonists/chemistry , Hormone Antagonists/pharmacology , Humans , Molecular Structure , Mutation , Protein Binding/drug effects , Receptors, Glucagon/genetics
15.
J Med Chem ; 41(23): 4607-14, 1998 Nov 05.
Article in English | MEDLINE | ID: mdl-9804700

ABSTRACT

Structural modifications requiring novel synthetic chemistry were made to the morpholine acetal human neurokinin-1 (hNK-1) receptor antagonist 4, and this resulted in the discovery of 2-(R)-(1-(R)-3, 5-bis(trifluoromethyl)phenylethoxy)-3-(S)-(4-fluoro)phenyl-4-(3-ox o-1 ,2,4-triazol-5-yl)methyl morpholine (17). This modified compound is a potent, long-acting hNK-1 receptor antagonist as evidenced by its ability to displace [125I]Substance P from hNK-1 receptors stably expressed in CHO cells (IC50 = 0.09 +/- 0.06 nM) and by the measurement of the rates of association (k1 = 2.8 +/- 1.1 x 10(8) M-1 min-1) and dissociation (k-1 = 0.0054 +/- 0.003 min-1) of 17 from hNK-1 expressed in Sf9 membranes which yields Kd = 19 +/- 12 pM and a t1/2 for receptor occupancy equal to 154 +/- 75 min. Inflammation in the guinea pig induced by a resiniferatoxin challenge (with NK-1 receptor activation mediating the subsequent increase in vascular permeability) is inhibited in a dose-dependent manner by the oral preadmininstration of 17 (IC50 (1 h) = 0.008 mg/kg; IC90 (24 h) = 1.8 mg/kg), indicating that this compound has good oral bioavailbility and peripheral duration of action. Central hNK-1 receptor stimulation is also inhibited by the systemic preadministration of 17 as shown by its ability to block an NK-1 agonist-induced foot tapping response in gerbils (IC50 (4 h) = 0.04 +/- 0.006 mg/kg; IC50 (24 h) = 0.33 +/- 0.017 mg/kg) and by its antiemetic actions in the ferret against cisplatin challenge. The activity of 17 at extended time points in these preclinical animal models sets it apart from earlier morpholine antagonists (such as 4), and the piperidine antagonists 2 and 3 and could prove to be an advantage in the treatment of chronic disorders related to the actions of Substance P. In part on the basis of these data, 17 has been identified as a potential clinical candidate for the treatment of peripheral pain, migraine, chemotherapy-induced emesis, and various psychiatric disorders.


Subject(s)
Acetals/chemical synthesis , Morpholines/chemical synthesis , Neurokinin-1 Receptor Antagonists , Acetals/administration & dosage , Acetals/chemistry , Acetals/pharmacology , Administration, Oral , Animals , Aprepitant , Behavior, Animal/drug effects , Binding, Competitive , CHO Cells , Capillary Permeability/drug effects , Cell Line , Cricetinae , Diterpenes/immunology , Esophagus/blood supply , Esophagus/drug effects , Esophagus/immunology , Female , Ferrets , Gerbillinae , Hindlimb/physiology , Humans , Inflammation/immunology , Inflammation/prevention & control , Male , Morpholines/administration & dosage , Morpholines/chemistry , Morpholines/pharmacology , Trachea/blood supply , Trachea/drug effects , Trachea/immunology , Urinary Bladder/blood supply , Urinary Bladder/drug effects , Urinary Bladder/immunology , Vomiting/prevention & control
16.
J Med Chem ; 41(23): 4623-35, 1998 Nov 05.
Article in English | MEDLINE | ID: mdl-9804702

ABSTRACT

Previously reported studies from these laboratories described the design of a novel series of high-affinity NK1 antagonists based on the 4,4-disubstituted piperidine ring system. Further structure-activity studies have now established that for high NK1 affinity the benzyl ether side chain must be 3,5-disubstituted and highly lipophilic, the optimal side chain being the 3, 5-bis(trifluoromethyl)benzyl ether, 12 (hNK1 IC50 = 0.95 nM). Additional studies have shown that this class of NK1 antagonist tolerates a wider range of substituents on the piperidine nitrogen, including acyl (38) (hNK1 IC50 = 5.3 nM) and sulfonyl (39) (hNK1 IC50 = 5.7 nM) derivatives. Following preliminary pharmacokinetic analysis, two compounds (32 and 43) were selected for in vivo study in the resiniferotoxin-induced vascular leakage model, both showing excellent profiles (ID50 = 0.22 and 0.28 mg/kg, respectively).


Subject(s)
Neurokinin-1 Receptor Antagonists , Piperidines/chemical synthesis , Pyrrolidines/chemical synthesis , Thiazoles/chemical synthesis , Animals , CHO Cells , Capillary Permeability/drug effects , Cricetinae , Diterpenes/toxicity , Esophagus/blood supply , Esophagus/drug effects , Guinea Pigs , Inositol Phosphates/metabolism , Male , Piperidines/pharmacokinetics , Piperidines/pharmacology , Pyrrolidines/pharmacokinetics , Pyrrolidines/pharmacology , Radioligand Assay , Receptors, Neurokinin-1/biosynthesis , Structure-Activity Relationship , Thiazoles/pharmacokinetics
17.
Science ; 281(5383): 1640-5, 1998 Sep 11.
Article in English | MEDLINE | ID: mdl-9733503

ABSTRACT

The localization of substance P in brain regions that coordinate stress responses and receive convergent monoaminergic innervation suggested that substance P antagonists might have psychotherapeutic properties. Like clinically used antidepressant and anxiolytic drugs, substance P antagonists suppressed isolation-induced vocalizations in guinea pigs. In a placebo-controlled trial in patients with moderate to severe major depression, robust antidepressant effects of the substance P antagonist MK-869 were consistently observed. In preclinical studies, substance P antagonists did not interact with monoamine systems in the manner seen with established antidepressant drugs. These findings suggest that substance P may play an important role in psychiatric disorders.


Subject(s)
Antidepressive Agents, Second-Generation/therapeutic use , Depressive Disorder/drug therapy , Morpholines/therapeutic use , Neurokinin-1 Receptor Antagonists , Substance P/antagonists & inhibitors , Adolescent , Adult , Aged , Amygdala/drug effects , Amygdala/metabolism , Animals , Antidepressive Agents, Second-Generation/adverse effects , Antidepressive Agents, Second-Generation/metabolism , Antidepressive Agents, Second-Generation/pharmacology , Aprepitant , Behavior, Animal/drug effects , Brain/drug effects , Brain/metabolism , Depressive Disorder/etiology , Depressive Disorder/metabolism , Female , Gerbillinae , Guinea Pigs , Humans , Male , Middle Aged , Morpholines/adverse effects , Morpholines/metabolism , Morpholines/pharmacology , Norepinephrine/physiology , Paroxetine/therapeutic use , Receptors, Neurokinin-1/metabolism , Serotonin/physiology , Stress, Psychological/drug therapy , Substance P/metabolism , Vocalization, Animal/drug effects
18.
Acad Med ; 73(4): 370-9, 1998 Apr.
Article in English | MEDLINE | ID: mdl-9580713

ABSTRACT

The authors present an overview of current graduate medical education (GME) issues, particularly the financial challenges to teaching hospitals resulting from the Balanced Budget and Tax Payer Relief Acts of 1997 and other recent market-driven factors. They describe in detail the nature of Medicare GME payments before and after the 1997 legislation, with specific examples, and explain the negative financial impact of the legislation and aspects of the legislation that are designed to alleviate that impact. Other factors influencing GME program size and composition are also discussed, including oversupplies or shortages of physicians, the concern that teaching hospitals are using public funds to train international medical graduates, changing training requirements, etc. The authors also describe a recent consulting assignment during which they assisted a major teaching hospital to develop a GME strategy that was responsive to the organization's mission and patients and that took into account future GME financing challenges. Detailed explanations are given of how the consultants analyzed the hospital's GME programs and finances, developed and ranked key institution-specific program criteria (strategic, organizational and operational, and financial), and, in consultation with all key stakeholders, formulated a GME strategy specific to the institution's needs. The authors conclude by cautioning that each institution's GME strategy will be different, but that it is important for institutions to develop such strategies to better face future challenges.


Subject(s)
Education, Medical, Graduate/economics , Financial Management/economics , Hospitals, Teaching/economics , Marketing of Health Services/economics , Training Support/economics , Budgets/legislation & jurisprudence , Consultants , Education, Medical, Graduate/organization & administration , Education, Medical, Graduate/trends , Financial Management/organization & administration , Financial Management/trends , Financing, Organized , Forecasting , Foreign Medical Graduates , Hospitals, Teaching/organization & administration , Hospitals, Teaching/trends , Humans , International Educational Exchange , Internship and Residency/economics , Internship and Residency/organization & administration , Managed Care Programs/economics , Managed Care Programs/organization & administration , Marketing of Health Services/organization & administration , Medicare/economics , Medicare/legislation & jurisprudence , Organizational Objectives , Patient Care , Physicians/supply & distribution , Public Sector , Reimbursement Mechanisms/economics , Reimbursement Mechanisms/organization & administration , Reimbursement, Incentive/economics , Reimbursement, Incentive/organization & administration , Students, Medical , Taxes/legislation & jurisprudence , Training Support/organization & administration , Training Support/trends , United States
19.
Bioorg Med Chem Lett ; 8(14): 1845-50, 1998 Jul 21.
Article in English | MEDLINE | ID: mdl-9873445

ABSTRACT

A series of novel serine derived NK1 antagonists is described. The effect of variations in the N-benzyl, O-benzyl and serine groups are used to define the elements which are necessary for binding.


Subject(s)
Neurokinin-1 Receptor Antagonists , Piperidines/pharmacology , Serine/chemistry , Piperidines/chemistry , Stereoisomerism , Structure-Activity Relationship
20.
Bioorg Med Chem Lett ; 8(14): 1851-6, 1998 Jul 21.
Article in English | MEDLINE | ID: mdl-9873446

ABSTRACT

Modifications to the spirocyclic aryl sulfonamide portion of serine derived NK1 antagonists allow a partial pharmacophore model to be developed.


Subject(s)
Neurokinin-1 Receptor Antagonists , Piperidines/chemistry , Serine/chemistry , Sulfonamides/metabolism , Models, Chemical , Piperidines/pharmacology , Receptors, Neurokinin-1/metabolism , Structure-Activity Relationship
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