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Background: Colorectal cancer (CRC) is a leading cause of cancer-associated mortality worldwide. Despite being an essential component of systemic chemotherapy for advanced CRC, 5-fluorouracil (5-FU) clinical use has severe limitations, such as high toxicity, low selectivity and drug resistance. [V4Q5]dDAVP (1-deamino-4-valine-5-glutamine-8-D-arginine vasopressin) is a peptide vasopressin analog and a selective agonist of the arginine vasopressin type 2 membrane receptor (AVPR2), expressed in microvascular and tumor tissue. This synthetic compound has well-proven antitumor and antimetastatic activity in different tumor types, including metastatic CRC. The objective of this work was to assess the potential combinational benefits in preclinical CRC models after [V4Q5]dDAVP addition to 5-FU. Methods: Effects on cellular viability, cell cycle progression, apoptosis and molecular mechanisms associated to [V4Q5]dDAVP treatment in combination with 5-FU were evaluated in murine CT-26 and human COLO-205 cell lines. In vivo, impact of dual therapy was explored on CRC tumor growth and metastatic spread. Results: In CRC cells, [V4Q5]dDAVP (1 µM) addition to sub-IC50 5-FU concentrations resulted in the enhancement of cytostatic effects induced by chemotherapy. Reduction of cell viability after combined treatment was associated with cell cycle arrest in the G0/G1 phase, induction of apoptosis and increased gene expression of the cyclin-dependent kinase inhibitor p21 (CDKN1A) and the tumor suppressor p53 (TP53) in malignant cells, as assessed by flow cytometry, terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate (dUTP) nick end labeling (TUNEL), and quantitative reverse transcription polymerase chain reaction (qRT-PCR), respectively. In vivo, intravenous administration of [V4Q5]dDAVP (0.3 µg/kg) in combination with safe low doses of 5-FU (50 or 80 mg/kg for CT-26 or COLO-205 tumor models, respectively) effectively abrogated CRC growth, reducing aggressiveness of primary lesions and increasing survival of tumor-bearing mice. In addition, concomitant administration of [V4Q5]dDAVP and 5-FU inhibited pulmonary metastasis formation by CT-26 cells in immunocompetent mice, especially reducing macrometastatic disease. Conclusions: [V4Q5]dDAVP seems to enhance the efficacy of 5-FU-based chemotherapy in CRC by modulating tumor progression, as well as metastatic dissemination, suggesting its potential role as a safe and cost-effective co-adjuvant agent for the management of advanced CRC.
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Abstract Objective To explore whether Cyclic Adenosine Monophosphate (cAMP)-Epac1 signaling is activated in 1-Desamino-8-D-arginine-Vasopressin-induced Endolymphatic Hydrops (DDAVP-induced EH) and to provide new insight for further in-depth study of DDAVP-induced EH. Methods Eighteen healthy, red-eyed guinea pigs (36 ears) weighing 200-350 g were randomly divided into three groups: the control group, which received intraperitoneal injection of sterile saline (same volume as that in the other two groups) for 7 consecutive days; the DDAVP-7d group, which received intraperitoneal injection of 10 mg/mL/kg DDAVP for 7 consecutive days; and the DDAVP-14d group, which received intraperitoneal injection of 10 μg/mL/kg DDAVP for 14 consecutive days. After successful modeling, all animals were sacrificed, and cochlea tissues were collected to detect the mRNA and protein expression of the exchange protein directly activated by cAMP-1 and 2 (Epac1, Epac2), and Repressor Activator Protein-1 (Rap1) by Reverse Transcription (RT)-PCR and western blotting, respectively. Results Compared to the control group, the relative mRNA expression of Epac1, Epac2, Rap1A, and Rap1B in the cochlea tissue of the DDAVP-7d group was significantly higher (p< 0.05), while no significant difference in Rap1 GTPase activating protein (Rap1gap) mRNA expression was found between the two groups. The relative mRNA expression of Epac1, Rap1A, Rap1B, and Rap1gap in the cochlea tissue of the DDAVP-14d group was significantly higher than that of the control group (p< 0.05), while no significant difference in Epac2 mRNA expression was found between the DDAVP-14d and control groups. Comparison between the DDAVP-14d and DDAVP-7d groups showed that the DDAVP-14d group had significantly lower Epac2 and Rap1A (p< 0.05) and higher Rap1gap (p < 0.05) mRNA expression in the cochlea tissue than that of the DDAVP-7d group, while no significant differences in Epac1 and Rap1B mRNA expression were found between the two groups. Western blotting showed that Epac1 protein expression in the cochlea tissue was the highest in the DDAVP-14d group, followed by that in the DDAVP-7d group, and was the lowest in the control group, showing significant differences between groups (p< 0.05); Rap1 protein expression in the cochlea tissue was the highest in the DDAVP-7d group, followed by the DDAVP-14d group, and was the lowest in the control group, showing significant differences between groups (p< 0.05); no significant differences in Epac2 protein expression in the cochlea tissue were found among the three groups. Conclusion DDAVP upregulated Epac1 protein expression in the guinea pig cochlea, leading to activation of the inner ear cAMP-Epac1 signaling pathway. This may be an important mechanism by which DDAVP regulates endolymphatic metabolism to induce EH and affect inner ear function. Oxford Centre for Evidence-Based Medicine 2011 Levels of Evidence Level 5.
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OBJECTIVE: To explore whether Cyclic Adenosine Monophosphate (cAMP)-Epac1 signaling is activated in 1-Desamino-8-D-arginine-Vasopressin-induced Endolymphatic Hydrops (DDAVP-induced EH) and to provide new insight for further in-depth study of DDAVP-induced EH. METHODS: Eighteen healthy, red-eyed guinea pigs (36 ears) weighing 200-350â¯g were randomly divided into three groups: the control group, which received intraperitoneal injection of sterile saline (same volume as that in the other two groups) for 7 consecutive days; the DDAVP-7d group, which received intraperitoneal injection of 10â¯mg/mL/kg DDAVP for 7 consecutive days; and the DDAVP-14d group, which received intraperitoneal injection of 10⯵g/mL/kg DDAVP for 14 consecutive days. After successful modeling, all animals were sacrificed, and cochlea tissues were collected to detect the mRNA and protein expression of the exchange protein directly activated by cAMP-1 and 2 (Epac1, Epac2), and Repressor Activator Protein-1 (Rap1) by Reverse Transcription (RT)-PCR and western blotting, respectively. RESULTS: Compared to the control group, the relative mRNA expression of Epac1, Epac2, Rap1A, and Rap1B in the cochlea tissue of the DDAVP-7d group was significantly higher (pâ¯<⯠0.05), while no significant difference in Rap1 GTPase activating protein (Rap1gap) mRNA expression was found between the two groups. The relative mRNA expression of Epac1, Rap1A, Rap1B, and Rap1gap in the cochlea tissue of the DDAVP-14d group was significantly higher than that of the control group (pâ¯<⯠0.05), while no significant difference in Epac2 mRNA expression was found between the DDAVP-14d and control groups. Comparison between the DDAVP-14d and DDAVP-7d groups showed that the DDAVP-14d group had significantly lower Epac2 and Rap1A (pâ¯<⯠0.05) and higher Rap1gap (p < 0.05) mRNA expression in the cochlea tissue than that of the DDAVP-7d group, while no significant differences in Epac1 and Rap1B mRNA expression were found between the two groups. Western blotting showed that Epac1 protein expression in the cochlea tissue was the highest in the DDAVP-14d group, followed by that in the DDAVP-7d group, and was the lowest in the control group, showing significant differences between groups (pâ¯<⯠0.05); Rap1 protein expression in the cochlea tissue was the highest in the DDAVP-7d group, followed by the DDAVP-14d group, and was the lowest in the control group, showing significant differences between groups (pâ¯<⯠0.05); no significant differences in Epac2 protein expression in the cochlea tissue were found among the three groups. CONCLUSION: DDAVP upregulated Epac1 protein expression in the guinea pig cochlea, leading to activation of the inner ear cAMP-Epac1 signaling pathway. This may be an important mechanism by which DDAVP regulates endolymphatic metabolism to induce EH and affect inner ear function. OXFORD CENTRE FOR EVIDENCE-BASED MEDICINE 2011 LEVELS OF EVIDENCE: Level 5.
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Orelha Interna , Hidropisia Endolinfática , Cobaias , Animais , Desamino Arginina Vasopressina/farmacologia , Transdução de Sinais , Hidropisia Endolinfática/induzido quimicamente , CócleaRESUMO
ABSTRACT Introduction: von Willebrand's disease (VWD) is the most common inherited bleeding disorder. The 1-desamino-8-d-arginine vasopressin (DDAVP) is the treatment of choice for most responsive patients with VWD. The aim of this study was to evaluate DDAVP use in the management of VWD. Method: We implemented a survey targeting medical doctors involved in the management of VWD in Brazil. Data was collected during a national congress on Hematology in November 2017. Main results: A total of 51/80 (63.8%) questionnaires were collected. Most participants (76.2%) were hematologists who assisted adult patients and approximately 60% worked at hemophilia treatment centers (HTCs). Approximately half of participants who reported treating patients with VWD, assisted on average, less than 5 patients per month, and approximately 60% declared not having used any DDAVP for treating VWD in the previous year. However, most participants (70%) prescribed FVIII-containing VWF concentrate (VWF/FVIII) for 1-10 patients in the previous year. More than 80% of the participants recognized the main indications for DDAVP. Physicians who recognized indication for DDAVP for type 1 VWD more often had prescribed DDAVP in previous year (p = 0.03). Barriers for prescribing DDAVP varied and included unavailability of laboratory facilities and consumables for DDAVP testing and lack of skills on its prescription. Conclusion: The DDAVP is currently underused in Brazil, as opposed to the excessive use of VWF/FVIII in VWD patients. We suggest the adoption of measures targeting educational and auditing programs. Furthermore, availability of laboratory reagents is needed to evaluate response and increment the correct use of DDAVP.
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Doenças de von Willebrand/terapia , Desamino Arginina Vasopressina/uso terapêutico , Brasil , Inquéritos e QuestionáriosRESUMO
INTRODUCTION: von Willebrand's disease (VWD) is the most common inherited bleeding disorder. The 1-desamino-8-d-arginine vasopressin (DDAVP) is the treatment of choice for most responsive patients with VWD. The aim of this study was to evaluate DDAVP use in the management of VWD. METHOD: We implemented a survey targeting medical doctors involved in the management of VWD in Brazil. Data was collected during a national congress on Hematology in November 2017. MAIN RESULTS: A total of 51/80 (63.8%) questionnaires were collected. Most participants (76.2%) were hematologists who assisted adult patients and approximately 60% worked at hemophilia treatment centers (HTCs). Approximately half of participants who reported treating patients with VWD, assisted on average, less than 5 patients per month, and approximately 60% declared not having used any DDAVP for treating VWD in the previous year. However, most participants (70%) prescribed FVIII-containing VWF concentrate (VWF/FVIII) for 1-10 patients in the previous year. More than 80% of the participants recognized the main indications for DDAVP. Physicians who recognized indication for DDAVP for type 1 VWD more often had prescribed DDAVP in previous year (pâ¯=⯠0.03). Barriers for prescribing DDAVP varied and included unavailability of laboratory facilities and consumables for DDAVP testing and lack of skills on its prescription. CONCLUSION: The DDAVP is currently underused in Brazil, as opposed to the excessive use of VWF/FVIII in VWD patients. We suggest the adoption of measures targeting educational and auditing programs. Furthermore, availability of laboratory reagents is needed to evaluate response and increment the correct use of DDAVP.
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Despite the increased worldwide awareness, over the last decade, of the platelet-type von Willebrand Disease (PT-VWD), many uncertainties remain around this rare platelet bleeding disorder. This report aims to correctly identify and study the phenotype of new patients and highlights the diagnostic and therapeutic challenges this disease remains to pose. We describe four PT-VWD cases confirmed by genetic analysis in which either the diagnosis and/or the treatment posed challenge. We provide the details of the clinical presentation, laboratory analysis, and the treatment and the responses in each case. We show that in addition to type 2B VWD, PT-VWD can be misdiagnosed as idiopathic thrombocytopenic purpura, neonatal alloimmune thrombocytopenia, and unexplained gestational thrombocytopenia. The disease can be diagnosed as early as 1 year of age and with phenotypically normal parents. Bleeding in some patients can be managed successfully using Humate P and DDAVP combined with tranexamic acid with no significant thrombocytopenia. We provide for the first time an evidence of an efficient response to rFVIIa in PT-VWD. Anaphylactic reaction to VWF preparations may be related to PT-VWD and the development of HLA antibodies is not uncommon. Progressive thrombocytopenia with normal VWF levels can be seen with PT-VWD and the platelet count was normalized at 2.5 weeks postpartum in one case. We conclude that these studies represent a record of clinical observations/interventions that help improve diagnoses/management of PT-VWD, highlight the variations in age and clinical presentations, laboratory diagnostic approaches, the importance of genetic testing for accurate diagnosis and consideration of therapeutic alternatives.
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Desamino Arginina Vasopressina/administração & dosagem , Fator VIII/administração & dosagem , Fator VIIa/administração & dosagem , Hemorragia , Ácido Tranexâmico/administração & dosagem , Doenças de von Willebrand , Adolescente , Pré-Escolar , Quimioterapia Combinada/métodos , Feminino , Hemorragia/sangue , Hemorragia/diagnóstico , Hemorragia/tratamento farmacológico , Humanos , Recém-Nascido , Masculino , Proteínas Recombinantes/administração & dosagem , Doenças de von Willebrand/sangue , Doenças de von Willebrand/diagnóstico , Doenças de von Willebrand/tratamento farmacológicoRESUMO
[V(4)Q(5)]dDAVP is a novel 2nd generation vasopressin analogue with robust antitumour activity against metastatic breast cancer. We recently reported that, by acting on vasopressin V2r membrane receptor present in tumour cells and microvascular endothelium, [V(4)Q(5)]dDAVP inhibits angiogenesis and metastatic progression of the disease without overt toxicity. Despite chemotherapy remaining as a primary therapeutic option for aggressive breast cancer, its use is limited by low selectivity and associated adverse effects. In this regard, we evaluated potential combinational benefits by adding [V(4)Q(5)]dDAVP to standard-of-care chemotherapy. In vitro, combination of [V(4)Q(5)]dDAVP with sub-IC50 concentrations of paclitaxel or carmustine resulted in a cooperative inhibition of breast cancer cell growth in comparison to single-agent therapy. In vivo antitumour efficacy of [V(4)Q(5)]dDAVP addition to chemotherapy was first evaluated using the triple-negative MDA-MB-231 breast cancer xenograft model. Tumour-bearing mice were treated with i.v. injections of [V(4)Q(5)]dDAVP (0.3 µg/kg, thrice weekly) in combination with weekly cycles of paclitaxel (10 mg/kg i.p.). After 6 weeks of treatment, combination regimen resulted in greater tumour growth inhibition compared to monotherapy. [V(4)Q(5)]dDAVP addition was also associated with reduction of local aggressiveness, and impairment of tumour invasion and infiltration of the skin. Benefits of combined therapy were confirmed in the hormone-independent and metastatic F3II breast cancer model by combining [V(4)Q(5)]dDAVP with carmustine (25 mg/kg i.p.). Interestingly, [V(4)Q(5)]dDAVP plus cytotoxic agents severely impaired colony forming ability of tumour cells and inhibited breast cancer metastasis to lung. The present study shows that [V(4)Q(5)]dDAVP may complement conventional chemotherapy by modulating metastatic progression and early stages of microtumour establishment, and thus supports further preclinical testing of the compound for the management of aggressive breast cancer.
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Antineoplásicos/farmacologia , Neoplasias da Mama/prevenção & controle , Desamino Arginina Vasopressina/análogos & derivados , Neoplasias Pulmonares/prevenção & controle , Animais , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Proliferação de Células , Desamino Arginina Vasopressina/farmacologia , Quimioterapia Combinada , Feminino , Humanos , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/secundário , Camundongos , Camundongos Endogâmicos BALB C , Neovascularização Patológica , Receptores de Vasopressinas/metabolismo , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Desmopressin (dDAVP) is a well-known peptide analog of the antidiuretic hormone vasopressin, used to prevent excessive bleeding during surgical procedures. dDAVP increases hemostatic mediators, such as the von Willebrand factor (vWF), recently considered a key element in resistance to metastasis. Studies in mouse models and veterinary trials in dogs with locally-advanced mammary tumors demonstrated that high doses of perioperative dDAVP inhibited lymph node and early blood-borne metastasis and significantly prolonged survival. We conducted a phase II dose-escalation trial in patients with breast cancer, administering a lyophilized formulation of dDAVP by intravenous infusion in saline, 30-60 min before and 24 h after surgical resection. Primary endpoints were safety and tolerability, as well as selection of the best dose for cancer surgery. Secondary endpoints included surgical bleeding, plasma levels of vWF, and circulating tumor cells (CTCs) as measured by quantitative PCR of cytokeratin-19 transcripts. Only 2 of a total of 20 patients experienced reversible adverse events, including hyponatremia (grade 4) and hypersensitivity reaction (grade 2). Reactions were adequately managed by slowing the infusion rate. A reduced intraoperative bleeding was noted with increasing doses of dDAVP. Treatment was associated with higher vWF plasma levels and a postoperative drop in CTC counts. At the highest dose level evaluated (2 µg/kg) dDAVP appeared safe when administered in two slow infusions of 1 µg/kg, before and after surgery. Clinical trials to establish the effectiveness of adjunctive perioperative dDAVP therapy are warranted. This trial is registered on www.clinicaltrials.gov (NCT01606072).
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A enurese noturna é definida como micção involuntária durante o sono, pelo menos duas vezes por semana, em crianças sem anomalias congênitas ou adquiridas do trato urinário ou sistema nervoso, em idade que o controle esfincteriano habitualmente está presente. O principal objetivo deste trabalho é abordar os mais diversos tipos de tratamento da enurese, classificada como primária ou secundária, quanto à evolução e, em relação aos sintomas, como monossintomática (simples) e polissintomática. O tratamento deve ser individualizado e com a fundamental coparticipação dos familiares, sendo que a motivação da criança é fundamental para seu sucesso. A literatura médica, em sua maioria, recomenda o início do tratamento a partir dos seis anos, pois a essa altura já pode interferir nas relações sociais infantis.A terapia farmacológica, principalmente com desmopressina (DDAVP) e anticolinérgicos, para a enurese noturna é apresentada no trabalho. O alarme urinário, para a Sociedade Internacional de Continência, parece ser o tratamento mais eficaz, atingindo até 79% de sucesso.
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We review the clinical and biochemical criteria used for evaluation of the transsphenoidal pituitary surgery results in the treatment of Cushing's disease (CD). Firstly, we discuss the pathophysiology of the hypothalamic-pituitary-adrenal axis in normal subjects and patients with CD. Considering the series published in the last 25 years, we observed a significant variation in the remission or cure criteria, including the choice of biochemical tests, timing, threshold values to define remission, and the interference of glucocorticoid replacement or previous treatment. In this context we emphasize serum cortisol levels obtained early (from hours to 12 days) in the postoperative period without any glucocorticoid replacement or treatment. Our experience demonstrates that: (i) early cortisol < 5 to 7 µg/dl, (ii) a period of glucocorticoid dependence > 6 mo, (iii) absence of response of cortisol/ACTH to CRH or DDAVP, (iv) return of dexamethasone suppression, and circadian rhythm of cortisol are appropriate indices of remission of CD. In patients with undetectable cortisol levels early after surgery, recurrence seems to be low. Finally, although certain biochemical patterns are more suggestive of remission or surgical failure, none has been proven to be completely accurate, with recurrence observed in approximately 10 to 15 percent of the patients in long-term follow-up. We recommended that patients with CD should have long-term monitoring of the CRH-ACTH-cortisol axis and associated co-morbidities, especially hypopituitarism, diabetes mellitus, hypertension, cardiovascular disturbances, and osteoporosis.
Neste artigo, são revisados os principais critérios clínicos e hormonais utilizados para avaliação do tratamento cirúrgico da Doença de Cushing (DC). Inicialmente são comentados aspectos fisiopatológicos que orientam a avaliação hormonal e os principais fatores clínicos, laboratoriais, cirúrgicos e histológicos associados com melhores resultados, observados nas principais séries da literatura e em pacientes acompanhados prospectivamente pelos autores. Foram revisados, também, critérios adotados nas principais séries da literatura, nos últimos 25 anos, chamando-se atenção para as dosagens hormonais, o momento em que foram realizadas, a possibilidade de interferência de tratamentos prévios e da reposição glicocorticóide. À seguir, essas dosagens são discutidas salientando-se a importância do cortisol obtido seqüencialmente no pós-operatório e sem a interferência de reposição glicocorticóide. A experiência prospectiva dos autores, recentemente referendada na literatura, demonstra que valores de cortisol < 5 a 7 µg/dl associados com um período de dependência aos glicocorticóides > 6 meses, ausência de resposta do ACTH/cortisol ao DDAVP e/ou CRH, retorno da supressão à dexametasona e do ritmo circadiano, estão associados com remissão da DC. Em pacientes com cortisol indetectável após cirurgia transesfenoidal, a chance de recidiva parece ser menor do que naqueles em que se observa cortisol detectável. Finalmente, chamamos a atenção para que, mesmo adotando critérios rígidos de avaliação, a recidiva da DC pode ocorrer a longo prazo em até 15 por cento dos casos, recomendando-se, portanto, que esses pacientes sejam acompanhados por tempo indeterminado, com monitorização cuidadosa do eixo CRH-ACTH-cortisol e de suas co-morbidades, especialmente hipopituitarismo, diabete melito, hipertensão arterial, alterações cardiovasculares e osteoporose.