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2.
Brachytherapy ; 20(3): 576-583, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33478906

RESUMO

PURPOSE: To report 8-year clinical outcome with high-dose-rate brachytherapy (HDRBT) boost using MRI-only workflow for intermediate (IR) and high-risk (HR) prostate cancer (PC) patients. METHODS AND MATERIALS: Fifty-two patients were treated with 46-60 Gy of 3D conformal radiotherapy preceded and/or followed by a single dose of 8-10 Gy MRI-guided HDRBT. Interventions were performed in a 0.35 T MRI scanner. Trajectory planning, navigation, contouring, catheter reconstruction, and dose calculation were exclusively based on MRI images. Biochemical relapse-free- (BRFS), local relapse-free- (LRFS), distant metastasis-free- (DMFS), cancer-specific-(CCS) and overall survival (OS) were analyzed. Late morbidity was scored using the Common Terminology Criteria for Adverse Events (CTCAE 4.0) combined with RTOG (Radiation Therapy Oncology Group) scale for urinary toxicity and rectal urgency (RU) determined by Yeoh. RESULTS: Median follow-up time was 107 (range: 19-143) months. The 8-year actuarial rates of BRFS, LRFS, DMFS, CSS and OS were 85.7%, 97%, 97.6%, and 77.6%, respectively. There were no Gr.3 GI side effects. The 8-year actuarial rate of Gr.2 proctitis was 4%. The 8-year cumulative incidence of Gr.3 GU side effects was 8%, including two urinary stenoses (5%) and one cystitis (3%). EPIC urinary and bowel scores did not change significantly over time. CONCLUSIONS: MRI-only HDR-BT boost with moderate dose escalation provides excellent 8-year disease control with a favorable toxicity profile for IRPC and HRPC patients. Our results support the clinical importance of MRI across the BT workflow.


Assuntos
Braquiterapia , Neoplasias da Próstata , Braquiterapia/métodos , Seguimentos , Humanos , Imageamento por Ressonância Magnética , Masculino , Recidiva Local de Neoplasia , Projetos Piloto , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/radioterapia , Dosagem Radioterapêutica , Fluxo de Trabalho
3.
Orv Hetil ; 161(11): 425-433, 2020 Mar.
Artigo em Húngaro | MEDLINE | ID: mdl-32148096

RESUMO

Introduction: Endometrial cancer is the most common invasive gynecologic malignancy in developed countries. The best survival rates are expected after surgical removal, thus the aim of a complex treatment is to achieve resecability in locally and locoregionally advanced disease. Aim: The primary purpose of this study was to evaluate if the neoadjuvant systemic treatment leads to better overall survival compared to irradiation solely. Method: From January 2015 to December 2018, we enrolled 28 patients diagnosed with irresecable, locally and locoregionally advanced high-risk endometrial carcinoma. Patients were treated by neoadjuvant paclitaxel-carboplatin, then radical hysterectomy, bilateral oophorectomy and lymphadenectomy were performed. Results: After administration of 6 cycles of carboplatin-paclitaxel, the control MR test showed tumor shrinkage in all patients. Complete resection was achieved in the case of every patient. Tumor residuum in lymph nodes was verified in 4 cases by pathological evaluation. The 2-year survival and the 2-year progression-free survival rates were 65,1% and 66,1%, respectively. The median overall survival was 16,5 months. Conclusion: Neoadjuvant treatment can be an effective approach in providing the conditions for complete tumor resection, which may result in survival advantage. Despite multimodal treatment, prognosis is poor. Orv Hetil. 2020; 161(11): 425-433.


Assuntos
Carboplatina/uso terapêutico , Neoplasias do Endométrio/tratamento farmacológico , Neoplasias do Endométrio/cirurgia , Terapia Neoadjuvante , Paclitaxel/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica , Cisplatino/uso terapêutico , Neoplasias do Endométrio/mortalidade , Feminino , Humanos , Excisão de Linfonodo , Estadiamento de Neoplasias , Ovariectomia , Taxa de Sobrevida , Resultado do Tratamento
5.
Pathol Oncol Res ; 17(2): 315-24, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21221879

RESUMO

The aim of our pilot study was to demonstrate the feasibility and dosimetric quality of MR-guided HDR prostate brachytherapy in a low-field 0.35T open MRI scanner and to present our initial clinical experiences. 16 patients with intermediate- to high-risk localized prostate cancer were treated with 46-60 Gy of external beam radiotherapy preceded and/or followed by an 8 Gy MR-guided HDR boost. For interventions an MR compatible custom-made system, coaxial needles and plastic catheters were used. Template reconstruction, trajectory planning, image guidance, contouring and treatment planning were exclusively based on MR images. For treatment planning, dose-point- and anatomy-based inverse planning optimization was used. Image quality was found to be good to excellent in almost all cases. The mean catheter placement accuracy modeled by Rayleigh distribution was 2.9 mm with a sigma value of 2.3 mm. The mean and standard deviation (SD) of the dosimetric results for the target volume were the following: V100: 94.2 ± 4.3%, V150: 43.9 ± 6.8%, V200: 18.5 ± 5.9%. The mean D(0.1), D(1) and D1 values for the intraprostatic urethra were 117.6 ± 12.5%, 98.5 ± 19.9% and 122.3 ± 16.4%, respectively. Regarding the rectal wall the mean D(0.1), D(1) and D(2) values were 77.3 ± 7.2%, 64.8 ± 7.5%, and 53.2 ± 9.1%, respectively. The mean maximum dose for the inner rectal surface was 53.5 ± 9.2%. No RTOG Grade 3 or worse acute toxicities were observed. Our method seems to be a promising approach for performing feasible, accurate and high-quality MR-guided HDR prostate brachytherapy. To determine the long term side effects and outcome higher number of patients, additional follow-up is needed.


Assuntos
Braquiterapia/métodos , Neoplasias da Próstata/radioterapia , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia Assistida por Computador/métodos , Idoso , Estudos de Viabilidade , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Projetos Piloto , Neoplasias da Próstata/patologia
6.
Pathol Oncol Res ; 17(1): 17-23, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20383760

RESUMO

In the treatment of early stage breast cancer, breast conserving surgery (BCS) followed by whole breast irradiation (WBI) is the standard treatment. The impact of the tumor bed boost following WBI is well-defined, but there are various delivery methods. In this study we demonstrate our 4 year experience with the 3-D conformal boost technique. Between January 2004 and June 2005, 77 early stage (Stage I-II) breast cancer patients were treated in our institute with whole breast irradiation (WBI, 50.4 Gy in 28 fractions) after breast conserving surgery. Following WBI, 3-D conformal photon boost was delivered (10-16 Gy in five to eight fractions) for all patients. The clinical outcome was retrospectively recorded in terms of survival and local control. The side effect profile (fibrosis, fat necrosis and cosmetic outcome) was also recorded and studied. In our patient group the mean follow up time was 46.8 months (median: 52, range: 17-71, SD: 14.4) The 4-year probability of local tumor control was 96% (crude rate: 74/77-96.1%), the 4-year probability of overall survival was 96% (crude rate: 74/77-96.1%) in this patient group. In case of the distant metastasis free survival the probability was 89, 5% (crude rate: 70/77-90, 1%). Probability of disease specific survival was 98% (crude rate: 76/77-98. 7%). Local relapse occurred in three cases (3.9%). In ten cases (12.9%) asymptomatic grade I-II breast fibrosis, in eight cases (10.4%) asymptomatic breast fat necrosis were registered. For 14 patients (18.2%) asymptomatic lung fibrosis was recorded on the control CT scans. In term of the relapse free survival, the close resection margin and the nodal positivity resulted in significant difference in favor of the clear resection margin group and the node negative group. In this study the 3-D conformal photon boost resulted in good local control and side effect profile. The presence of tumor bed clips resulted in significantly lower boost PTV volumes, but no correlation was found between the irradiated boost volume and the breast fibrosis. In the relapse free survival analysis, nodal negativity and clear margin status resulted in significantly better RFS.


Assuntos
Neoplasias da Mama/radioterapia , Radioterapia Conformacional , Adulto , Idoso , Neoplasias da Mama/mortalidade , Neoplasias da Mama/patologia , Terapia Combinada , Intervalo Livre de Doença , Feminino , Seguimentos , Humanos , Estimativa de Kaplan-Meier , Mastectomia Segmentar , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Estudos Retrospectivos
7.
J Mol Neurosci ; 28(2): 143-50, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16679554

RESUMO

Unlike mammals, rhythmic changes in serotonin N-acetyltransferase (arylalkylamine N-acetyltransferase [AANAT]) transcripts in chicken pineal cells are controlled by an oscillator located in the pinealocytes themselves, which is comprised of clock genes. Asimilar clock-dependent pathway has been postulated to regulate the retinal melatonin rhythm. In chicken retinal photoreceptor cells and pinealocytes, the chicken AANAT gene (cAANAT) is coexpressed with clock genes, including cBmal1 and cClock, which might regulate cAANAT transcription. Here, we have studied the temporal profile of cBmal1, cClock, and cAANAT mRNAexpressions in retinal cells in vivo with chickens housed in a 14/10-h light/dark (LD) cycle for 2 wk and in vitro cultured in a superfusion system for 4 LD cycles. mRNA levels of these genes were analyzed by RT-PCR and compared with their corresponding pineal transcripts. cBmal1 mRNA showed a peak during the light phase between Zeitgeber time (ZT) 8 and 10, preceding the amplitude of the nocturnal increase in cAANAT expression at ZT 16-17. Retinal cBmal1 and cAANAT mRNAs exhibited less robust cycling than their corresponding pineal transcripts in the same animal. cClock mRNAlevels failed to exhibit a well-detectable rhythm. The phase of the rhythms of retinal cBmal1 and cAANAT mRNAs suggests a link between retinal cBmal1 and cAANAT expressions similar to the regulation of pineal cAANAT transcription. Based on the highly conserved nature of the clockwork, it is reasonable to consider that chicken retina and pineal gland might serve as a useful tool for the development of drugs that could influence clock function in man.


Assuntos
Arilalquilamina N-Acetiltransferase/metabolismo , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Ritmo Circadiano/fisiologia , Regulação da Expressão Gênica , Células Fotorreceptoras/fisiologia , Glândula Pineal/citologia , RNA Mensageiro/metabolismo , Fatores de Transcrição ARNTL , Animais , Arilalquilamina N-Acetiltransferase/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Relógios Biológicos/fisiologia , Proteínas CLOCK , Células Cultivadas , Galinhas , Humanos , Masculino , Melatonina/metabolismo , Células Fotorreceptoras/citologia , Retina/citologia , Retina/fisiologia , Fatores de Tempo , Transativadores/genética , Transativadores/metabolismo
8.
Proc Natl Acad Sci U S A ; 103(12): 4610-5, 2006 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-16537407

RESUMO

Antagonists of growth hormone-releasing hormone (GHRH) synthesized previously inhibit proliferation of various human cancers, but derivatisation with fatty acids could enhance their clinical efficacy. We synthesized a series of antagonists of GHRH(1-29)NH(2) acylated at the N terminus with monocarboxylic or alpha,omega-dicarboxylic acids containing six to sixteen carbon atoms. These peptides are analogs of prior potent antagonists JV-1-36, JV-1-38, and JV-1-65 with phenylacetyl group at their N terminus. Several new analogs, including MZ-J-7-46 and MZ-J-7-30, more effectively inhibited GHRH-induced GH release in vitro in a superfused rat pituitary system than their parent compound JV-1-36 and had increased binding affinities to rat pituitary GHRH receptors, but they showed weaker inhibition of GH release in vivo than JV-1-36. All antagonists acylated with fatty acids containing 8-14 carbon atoms inhibited the proliferation of MiaPaCa-2 human pancreatic cancer cells in vitro better than JV-1-36 or JV-1-65. GHRH antagonist MZ-J-7-114 (5 mug/day) significantly suppressed the growth of PC-3 human androgen-independent prostate cancers xenografted into nude mice and reduced serum IGF-I levels, whereas antagonist JV-1-38 had no effect at the dose of 10 mug/day. GHRH antagonists including MZ-J-7-46 and MZ-J-7-114 acylated with octanoic acid and MZ-J-7-30 and MZ-J-7-110 acylated with 1,12-dodecanedicarboxylic acid represent relevant improvements over earlier antagonists. These and previous results suggest that this class of GHRH antagonists might be effective in the treatment of various cancers.


Assuntos
Antineoplásicos/química , Antineoplásicos/farmacologia , Lipoproteínas/química , Lipoproteínas/farmacologia , Sermorelina/antagonistas & inibidores , Animais , Antineoplásicos/síntese química , Ácidos Dicarboxílicos/química , Humanos , Lipoproteínas/síntese química , Masculino , Peptídeos/síntese química , Peptídeos/química , Peptídeos/farmacologia , Hipófise/efeitos dos fármacos , Hipófise/metabolismo , Ratos , Receptores de Neuropeptídeos/efeitos dos fármacos , Receptores de Hormônios Reguladores de Hormônio Hipofisário/efeitos dos fármacos , Sermorelina/metabolismo , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
9.
Mol Cell Endocrinol ; 249(1-2): 84-91, 2006 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-16517056

RESUMO

In birds, rhythmic changes in pineal serotonin N-acetyltransferase (arylalkylamine N-acetyltransferase, Aanat) transcripts are controlled by an oscillator located in the pinealocytes themselves which is comprised by clock genes. Our previous data indicated a temporal association between the expressions of chicken Bmal1 clock gene and Aanat suggesting a functional molecular link between them. Here, we studied the effect of cBmal1 antisense oligonucleotides containing locked nucleic acid on cAanat transcripts and melatonin production in cultured chicken pinealocytes transfected in superfusion system. These oligonucleotides synthesized for activating RNase H or blocking the binding of the translation machinery were able to reduce significantly cAanat transcription and melatonin secretion, whereas control inverted oligonucleotides were ineffective. These results indicate the key role of cBmal1 in the regulation of indole metabolism. The superfusion cell culture with reduced transfection toxicity may provide a useful tool for antisense drug design to influence the highly conserved clockwork also in man.


Assuntos
Arilalquilamina N-Acetiltransferase/antagonistas & inibidores , Fatores de Transcrição Hélice-Alça-Hélice Básicos/antagonistas & inibidores , Fatores de Transcrição Hélice-Alça-Hélice Básicos/fisiologia , Melatonina/metabolismo , Oligonucleotídeos Antissenso/farmacologia , Glândula Pineal/metabolismo , Fatores de Transcrição ARNTL , Animais , Arilalquilamina N-Acetiltransferase/genética , Arilalquilamina N-Acetiltransferase/metabolismo , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Galinhas/genética , Ritmo Circadiano/genética , Regulação da Expressão Gênica , Oligonucleotídeos , Oligonucleotídeos Antissenso/química , Glândula Pineal/citologia , RNA Mensageiro/fisiologia , Transfecção
10.
Proc Natl Acad Sci U S A ; 102(48): 17424-9, 2005 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-16299104

RESUMO

Various attempts to detect human pituitary growth hormone-releasing hormone receptor (pGHRH-R) in neoplastic extrapituitary tissues have thus far failed. Recently, four splice variants (SVs) of GHRH-R have been described, of which SV1 has the highest structural homology to pGHRH-R and likely plays a role in tumor growth. The aim of this study was to reinvestigate whether human tumors and normal human extrapituitary tissues express the pGHRH-R and to corroborate our previous findings on its SVs. Thus, we developed a real-time PCR method for the detection of the mRNA for the pGHRH-R, its SVs, and the GHRH peptide. Using real-time PCR, Western blotting, and radioligand-binding assays, we detected the mRNA for pGHRH-R and pGHRH-R protein in various human cancer cell lines grown in nude mice and in surgical specimens of human lung cancers. The expression of mRNA for SVs of pGHRH-R and GHRH was likewise found in xenografts of human non-Hodgkin's lymphomas, pancreatic cancer, glioblastoma, small-cell lung carcinomas, and in human nonmalignant prostate, liver, lung, kidney, and pituitary. Western blots showed that these normal and malignant human tissues contain SV1 protein and immunoreactive GHRH. Our results demonstrate that some normal human tissues and tumors express mRNA and protein for the pGHRH-R and its splice variants. These findings confirm and extend the concept that GHRH and its receptors play an important role in the pathophysiology of human cancers.


Assuntos
Processamento Alternativo/genética , Carcinoma de Células Pequenas/metabolismo , RNA Mensageiro/metabolismo , Receptores de Neuropeptídeos/metabolismo , Receptores de Hormônios Reguladores de Hormônio Hipofisário/metabolismo , Western Blotting , Linhagem Celular , Linhagem Celular Tumoral , Primers do DNA , Hormônio Liberador de Hormônio do Crescimento/genética , Humanos , Reação em Cadeia da Polimerase , Ensaio Radioligante , Receptores de Neuropeptídeos/genética , Receptores de Hormônios Reguladores de Hormônio Hipofisário/genética
11.
Proc Natl Acad Sci U S A ; 102(30): 10628-33, 2005 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-16027368

RESUMO

Antagonists of growth hormone-releasing hormone (GHRH) were shown to inhibit the growth of various cancers. We investigated the antitumor activity and the mechanism of action of GHRH antagonists in human non-Hodgkin's lymphomas (NHL). Nude mice bearing xenografts of RL and HT human NHL were treated with GHRH antagonists MZ-5-156 and MZ-J-7-138 at a dose of 40 microg twice daily. The concentrations of serum IGF-1 and GHRH, bFGF, and VEGF in tumor tissue were measured by radioimmunoassays. Expression of GHRH and splice variant 1 of the GHRH receptor in both cell lines was examined by RT-PCR. The effects of MZ-5-156, MZ-J-7-138 and GHRH on cell proliferation were evaluated in vitro. Treatment with MZ-5-156 and MZ-J-7-138 significantly (P < 0.05) inhibited the growth of RL and HT tumors by 59.9-73.9%. High-affinity binding sites for GHRH and mRNA for GHRH and splice variant-1 of the GHRH receptors were found on RL and HT tumors. RL and HT cells contained GHRH peptide, and their growth in vitro was significantly inhibited by both antagonists. IGF-I levels in serum of mice were significantly decreased by antagonist MZ-5-156. Therapy with GHRH antagonists also significantly reduced tumoral bFGF, whereas VEGF levels were not suppressed. Our findings suggest that GHRH antagonists inhibit the growth of RL and HT lymphomas by direct effects mediated by tumoral receptors for GHRH. GHRH antagonists could offer a new therapeutic modality for the management of advanced NHL.


Assuntos
Hormônio Liberador de Hormônio do Crescimento/antagonistas & inibidores , Linfoma não Hodgkin/tratamento farmacológico , Sermorelina/análogos & derivados , Animais , Linhagem Celular Tumoral , Primers do DNA , Relação Dose-Resposta a Droga , Feminino , Fatores de Crescimento de Fibroblastos/metabolismo , Hormônio Liberador de Hormônio do Crescimento/sangue , Humanos , Fator de Crescimento Insulin-Like I/metabolismo , Camundongos , Camundongos Nus , Radioimunoensaio , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Sermorelina/farmacologia , Sermorelina/uso terapêutico , Fator A de Crescimento do Endotélio Vascular/metabolismo
12.
J Clin Endocrinol Metab ; 90(6): 3614-21, 2005 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15784701

RESUMO

Antagonists of GHRH are being developed for the treatment of various cancers. In this study we investigated in vivo and in vitro the effects of the GHRH antagonist MZ-J-7-118 and its mechanism of action in HEC-1A human endometrial cancer. Treatment of nude mice bearing HEC-1A xenografts with 10 mug/d MZ-J-7-118 for 6 wk significantly inhibited the volume of HEC-1A tumors by 43%, tumor weight by 40% compared with controls and prolonged the tumor doubling time from 18.7 +/- 1.4 to 25.4 +/- 3.8 d. Administration of 20 mug MZ-J-7-118, sc, twice a day significantly (P < 0.05) decreased HEC-1A growth, as evidenced by a 57.9% decrease in tumor volume, a 50.7% reduction in tumor weight, and the extension of tumor doubling time from 17.5 +/- 2.8 to 36.4 +/- 6.5 d. Therapy with GHRH antagonists significantly decreased serum IGF-I levels in experiment 1, and significantly increased tumoral IGF-I levels in experiment 2 in treated mice. Levels of IGF-II and vascular endothelial growth factor-A in tumors were not changed. Specific high affinity binding sites for GHRH were found on HEC-1A tumor membranes using ligand competition assays with (125)I-labeled GHRH antagonist JV-1-42. MZ-J-7-118 displaced radiolabeled JV-1-42 with an IC(50) of 0.13 +/- 0.04 nm. The expression of mRNA for GHRH and splice variants of the GHRH receptor in HEC-1A tumors was demonstrated by real-time RT-PCR analysis. HEC-1A cells cultured in vitro secreted GHRH into the medium. The GHRH antagonist MZ-J-7-118 inhibited the growth of HEC-1A cells in vitro. Our results indicate that GHRH antagonists can reduce the growth of human endometrial cancer and could be used as an alternative adjuvant therapy for the management of endometrial cancer.


Assuntos
Neoplasias do Endométrio/patologia , Hormônio Liberador de Hormônio do Crescimento/antagonistas & inibidores , Sermorelina/toxicidade , Animais , Divisão Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Feminino , Humanos , Fator de Crescimento Insulin-Like I/metabolismo , Fator de Crescimento Insulin-Like II/metabolismo , Cinética , Camundongos , Camundongos Knockout , Transplante Heterólogo , Fator A de Crescimento do Endotélio Vascular/metabolismo
13.
Proc Natl Acad Sci U S A ; 101(42): 15160-5, 2004 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-15469915

RESUMO

Antagonists of growth hormone-releasing hormone (GHRH) inhibit the growth of various human cancers by multiple mechanisms, which include direct effects on tumor cells through the splice variants (SV) of the GHRH receptor. Our findings suggest that the tumoral protein encoded by SV 1 (SV1) is a likely functional receptor. The aim of this study was to develop a polyclonal antiserum against a polypeptide analog of segment 1-25 of the putative SV1 receptor protein. Rabbits were immunized with [Ala-23]SV1 (1-25)-Tyr-26-Cys-27-NH2 as a hapten, conjugated to BSA or keyhole limpet hemocyanin. The antisera thus generated were evaluated by RIA for binding to the radiolabeled hapten. The specificity and sensitivity of the antisera were studied on xenografts of RL and HT human non-Hodgkin's lymphomas. The sera raised against keyhole limpet hemocyanin-SV1 hapten, showed binding values of 50-75% at a 1:56,000 dilution. In Western blot analyses, the purified polyclonal antibody recognized a specific signal with a molecular mass of approximately 40 kDa in RL and HT lymphomas. This band corresponds to the estimated molecular mass of the GHRH receptor isoform encoded by SV1. RT-PCR and ligand binding studies also revealed the expression of SV1 and the presence of high-affinity binding sites for GHRH on RL and HT tumors. Because the antiserum developed recognizes the tumoral GHRH receptor protein encoded by SV1, it should be of value in various investigations.


Assuntos
Anticorpos/isolamento & purificação , Neoplasias/metabolismo , Receptores de Neuropeptídeos/imunologia , Receptores de Neuropeptídeos/metabolismo , Receptores de Hormônios Reguladores de Hormônio Hipofisário/imunologia , Receptores de Hormônios Reguladores de Hormônio Hipofisário/metabolismo , Animais , Linhagem Celular Tumoral , Feminino , Variação Genética , Humanos , Linfoma não Hodgkin/genética , Linfoma não Hodgkin/metabolismo , Camundongos , Camundongos Nus , Neoplasias/genética , Isoformas de Proteínas/genética , Isoformas de Proteínas/imunologia , Isoformas de Proteínas/metabolismo , Coelhos , Receptores de Neuropeptídeos/genética , Receptores de Hormônios Reguladores de Hormônio Hipofisário/genética , Transplante Heterólogo
14.
Proc Natl Acad Sci U S A ; 101(14): 4996-5001, 2004 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-15044692

RESUMO

Our previous studies showed that treatment of female rats with large doses of Cetrorelix, an antagonist of luteinizing hormone-releasing hormone (LHRH), reduces levels of serum LH, estradiol, progesterone, and the concentration of pituitary LHRH receptors (LHRH-Rs) and their mRNA expression. Serum LH and testosterone levels and pituitary LHRH-R in male rats are also decreased by high doses of Cetrorelix. This approach can be used for therapy of sex hormone-dependent cancers. However, in conditions where an incomplete hormone deprivation is indicated, lower doses of Cetrorelix may suffice. Thus, we investigated the effect of a 30-day treatment with a low-dose depot formulation of Cetrorelix (20-24 microg per kg per day) on the pituitary-gonadal axis of male and female rats. In both sexes, lower serum LH levels were observed on day 4 after administration. In males, LH returned to control levels by day 10, whereas in females, a rebound LH elevation occurred. Testosterone levels in male rats were decreased up to day 20, but on day 30, the values were similar to controls. In females, serum estradiol was reduced on day 4; however, by day 10 it returned to normal. Progesterone levels were diminished through the entire period. Female rats showed diestrous smears during the first week of treatment and prolonged estrous periods thereafter. The weights of testes and ovaries were significantly lower, but not the weights of prostate, seminal vesicles, and uterus. Pituitary LHRH-R mRNA and LHRH-R protein levels were not significantly different from the controls. Thus, the treatment with low doses of Cetrorelix did not seriously impair gonadal functions. The results suggest that Cetrorelix in low doses induces only a partial pituitary-gonadal inhibition and might be indicated for treatment of endometriosis, leiomyomas, and benign prostatic hyperplasia.


Assuntos
Hormônio Liberador de Gonadotropina/análogos & derivados , Hormônio Liberador de Gonadotropina/antagonistas & inibidores , Hormônio Liberador de Gonadotropina/farmacologia , Antagonistas de Hormônios/farmacologia , Hipófise/efeitos dos fármacos , Receptores LHRH/efeitos dos fármacos , Animais , Relação Dose-Resposta a Droga , Feminino , Hormônio Liberador de Gonadotropina/administração & dosagem , Antagonistas de Hormônios/administração & dosagem , Masculino , Hipófise/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley , Receptores LHRH/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa
15.
Proc Natl Acad Sci U S A ; 101(6): 1708-13, 2004 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-14755056

RESUMO

Antagonists of human growth hormone-releasing hormone (hGHRH) with increased potency and improved enzymatic and chemical stability are needed for potential clinical applications. We synthesized 21 antagonistic analogs of hGHRH(1-29)NH(2), substituted at positions 8, 9, and 10 of the common core sequence [phenylacetyl-Tyr(1), d-Arg(2,28), para-chloro-phenylalanine 6, Arg(9)/homoarginine 9, Tyr(10)/O-methyltyrosine 10, alpha-aminobutyric acid 15, norleucine 27, Har(29)] hGHRH(1-29)NH(2). Inhibitory effects on hGHRH-induced GH release were evaluated in vitro in a superfused rat pituitary system, as well as in vivo after i.v. injection into rats. The binding affinities of the peptides to pituitary GHRH receptors were also determined. Introduction of para-amidinophenylalanine 10 yielded antagonists JV-1-62 and -63 with the highest activities in vitro and lowest receptor dissociation constants (K(i) = 0.057-0.062 nM). Antagonists JV-1-62 and -63 also exhibited the strongest effect in vivo, significantly (P < 0.05-0.001) inhibiting hGHRH-induced GH release for at least 1 h. Para-aminophenylalanine 10 and O-ethyltyrosine 10 substitutions yielded antagonists potent in vitro, but His(10), 3,3'-diphenylalanine 10, 2-naphthylalanine 10, and cyclohexylalanine 10 modifications were detrimental. Antagonists containing citrulline 9 (in MZ-J-7-72), amidinophenylalanine 9 (in JV-1-65), His(9), d-Arg(9), citrulline 8, Ala(8), d-Ala(8), or alpha-aminobutyric acid 8 substituents also had high activity and receptor affinity in vitro. However, in vitro potencies of analogs with substitution in position 9 correlated poorly with acute endocrine effects in vivo, as exemplified by the weak and/or short inhibitory actions of antagonists JV-1-65 and MZ-J-7-72 on GH release in vivo. Nevertheless, antagonist JV-1-65 was more potent than JV-1-63 in tests on inhibition of the growth of human prostatic and lung cancer lines xenografted into nude mice. This indicates that oncological activity may be based on several mechanisms. hGHRH antagonists with improved efficacy could be useful for treatment of cancers that depend on insulin-like growth factors or GHRH.


Assuntos
Hormônio Liberador de Hormônio do Crescimento/antagonistas & inibidores , Animais , Hormônio do Crescimento/metabolismo , Hormônio Liberador de Hormônio do Crescimento/química , Hormônio Liberador de Hormônio do Crescimento/metabolismo , Hipófise/metabolismo , Ratos
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