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1.
Melanoma Res ; 33(3): 208-217, 2023 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-37015054

RESUMO

Pembrolizumab and nivolumab (anty-PD-1 antibody) are commonly used for the treatment of melanoma patients. However, their efficacy and safety have never been directly compared, leaving little guidance for clinicians to select the best therapy. The study included patients with inoperable or metastatic melanoma treated in first line with anti-PD-1 immunotherapy (nivolumab or pembrolizumab). In total 1037 patients were enrolled in the study, 455 (44%) patients were treated with pembrolizumab and 582 (56%) with nivolumab. The estimated median overall survival (OS) in the pembrolizumab and nivolumab groups was 17.4 and 20.0 months [ P = 0.2323; hazard ratio (HR), 1.1; 95% confidence interval (CI), 0.94-1.28], respectively, whereas the median progression-free survival (PFS) was 5.6 and 7.5 months ( P = 0.0941; HR, 1.13; 95% CI, 0.98-1.29), respectively. The estimated 2- and 3-year OS in the pembrolizumab and nivolumab groups were 42/34% and 47/37%, respectively, and the PFS was 25/21% and 29/23%, respectively. There were 391 (49%) immune-related adverse events (irAEs) of any grade during treatment, including 133 (42%) related to pembrolizumab treatment and 258 (53%) to nivolumab treatment. A total of 72 (9.6%) irAEs were in G3 or G4, including during pembrolizumab 29 (9%) and nivolumab 48 (11%). There were no differences in OS, PFS and overall response rates between nivolumab and pembrolizumab therapy in previously untreated patients with advanced/metastatic melanoma. There were no differences in the frequency of G1/G2 or G3/G4 irAEs. The choice of treatment should be based on the preferences of the patient and the clinician.


Assuntos
Melanoma , Neoplasias Cutâneas , Humanos , Nivolumabe/efeitos adversos , Melanoma/patologia , Neoplasias Cutâneas/tratamento farmacológico , Neoplasias Cutâneas/induzido quimicamente , Anticorpos Monoclonais Humanizados/efeitos adversos
2.
Target Oncol ; 18(2): 235-245, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36906728

RESUMO

BACKGROUND: Combined treatment with BRAFi and/or MEK inhibitors (MEKi) improves outcomes in advanced melanoma patients in comparison with monotherapy. OBJECTIVE: We aim to report real-world treatment efficacy and safety of vemurafenib (V) and vemurafenib + cobimetinib (V + C) from 10 years of practice. PATIENTS AND METHODS: A total of 275 consecutive patients with unresectable or metastatic BRAF mutated melanoma started first-line V or V + C treatment between 1 October 2013 and 31 December 2020. Survival analyses were performed using the Kaplan-Meier method, and Log-rank and Chi-square tests were used for comparison between groups. RESULTS: The estimated median overall survival (mOS) was 10.3 months in the V group, and 12.3 months in the V + C group (p = 0.0005; HR = 1.58, 95% CI 1.2-2.1), although the latter group of patients had lactate dehydrogenase elevated numerically more often. Estimated median progression-free survival (mPFS) was 5.5 months in the V group, and 8.3 months in the V + C group (p = 0.0002; HR = 1.62, 95% CI 1.3-2.1). Complete response, partial response, stable disease, and progressive disease as best responses were recorded in the V/V + C groups in 7%/10%, 52%/46%, 26%/28%, and 15%/16% of patients, respectively. The numbers of patients with any grade of adverse effects were similar in both groups. CONCLUSIONS: We confirmed significant improvement in the mOS and mPFS of unresectable and/or metastatic BRAF mutated-melanoma patients treated outside clinical trials with V + C as compared with V, with no major increase in toxicity for the combination.


Assuntos
Melanoma , Neoplasias Cutâneas , Humanos , Vemurafenib/farmacologia , Vemurafenib/uso terapêutico , Proteínas Proto-Oncogênicas B-raf/genética , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Melanoma/tratamento farmacológico , Melanoma/genética , Melanoma/patologia , Neoplasias Cutâneas/tratamento farmacológico , Neoplasias Cutâneas/genética , Mutação
3.
Dermatol Ther (Heidelb) ; 12(12): 2851-2862, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36333615

RESUMO

INTRODUCTION: Nodular melanoma (NM) is a rare subtype of melanoma, responsible for more than 40% of melanoma deaths, characterized by rapid growth and high metastatic potential. Only a few case studies concerning the dermoscopic presentations of giant nodular melanoma have been reported so far. OBJECTIVES: The aim of the study was to assess dermoscopic features of giant nodular melanomas in special locations, along with their clinical and histopathologic aspects. METHODS: Among 120 patients with histopathologically confirmed melanoma treated by the Skin Cancer and Melanoma Team between September 2020 and February 2021, we identified six patients with giant nodular melanoma in special locations. We retrospectively assessed the archived dermoscopic images to determine the dermoscopic features of these tumors. RESULTS: The group consisted of six cases of giant melanoma in special locations, including the scalp (4/6) and the heel (2/6). The giant tumors were large in size (at least 5 cm in diameter). The most common dermoscopic structures in polarized light included asymmetric distribution of dermoscopic structures, the presence of structureless, multicolored zones (showing three or more colors), and the presence of white perpendicular lines or small, pink globules. CONCLUSIONS: It seems that there are no significant differences in dermoscopy between small and giant melanomas; however, further studies should be conducted on a larger scale.

4.
BMC Cancer ; 22(1): 432, 2022 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-35443624

RESUMO

BACKGROUND: Malignant pleural mesothelioma (MPM) is a rare, aggressive malignancy of the pleural cavity linked to asbestos exposure. The combination of pemetrexed and platinum is a standard first-line therapy for malignant pleural mesothelioma. Despite some progress, almost all MPM patients experience progression after first-line therapy. The second-line treatment is still being under discussion and there are very limited data available on the second-line and subsequent treatments. METHODS: The retrospective analysis included 57 patients (16 females and 41 males) from two Polish oncological institutions treated for advanced mesothelioma between 2013 and 2019. We analysed the efficacy of first-line and second-line therapy: progression-free survival (PFS), overall survival (OS), overall response rate (ORR). RESULTS: In the first-line treatment, 55 patients received pemetrexed-based chemotherapy (PBC) and two cisplatin in monotherapy. Patients' characteristics at baseline: median age was 64.2 years, ECOG PS ≤ 1 (86.2%), epithelial histology (85.7%). Median PFS and OS were 7.6 months and 14 months, respectively. Patients with ECOG PS ≤ 1 vs > 1 had a longer median OS (14.8 months vs 9.7 months, p = 0.057). One-year OS and PFS were 60.9% and 32.0%, respectively. Disease control rate (DCR) was 82.5%. Response to first-line therapy: PFS ≥ 6 months and PFS ≥ 12 months had a significant impact on median OS. Twelve patients received second-line therapy (seven PBC and five other cytotoxic single agents: navelbine, gemcitabine, or adriamycin/vincristine/methotrexate triplet). Median PFS and OS were 3.7 months and 7.2 months, respectively. DCR was 83%. One-year OS and PFS were 37% and 16.7%, respectively. In the group receiving PBC, OS was prolonged by 4.5 months compared to the non-PBC group (6.0 months vs 10.5 months, p = 0.47). CONCLUSION: Patients who benefited from first-line therapy and had prolonged PFS at first-line and achieve PFS longer than 6 months at first-line should be offered second-line treatment. Consideration of retreatment with the same cytotoxic agent could to be a viable option when no other treatment are available.


Assuntos
Neoplasias Pulmonares , Mesotelioma Maligno , Mesotelioma , Neoplasias Pleurais , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Feminino , Humanos , Neoplasias Pulmonares/patologia , Masculino , Mesotelioma/patologia , Pessoa de Meia-Idade , Pemetrexede/uso terapêutico , Estudos Retrospectivos , Resultado do Tratamento
5.
Cancers (Basel) ; 14(2)2022 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-35053584

RESUMO

Merkel cell carcinoma (MCC) is a rare, aggressive skin cancer with a high risk of recurrence and poor prognosis. The treatment of locally advanced disease involves surgery and radiotherapy. To analyze real-life treatment patterns and clinical outcomes, we conducted a retrospective analysis of data from 161 MCC patients treated with curative intent in four oncological centers in Poland. The median age at diagnosis was 72 years (30-94); 49.7% were male. Lymph node (LN) involvement at diagnosis was found in 26.9% of patients. Sentinel lymph node biopsy (SLNB) was performed in 36.5% of patients (positive in 10.5%), and 51.9% of patients received perioperative treatment. The relapse rate was 38.3%. With the median follow-up of 2.3 years, the median disease-free survival (DFS) was not reached, and the 1-year rate was 65%. The negative independent risk factors for DFS were male gender, metastases in LN at diagnosis, no SLNB in patients without clinical nodal metastases, and no perioperative radiotherapy. The estimated median overall survival (OS) was 6.9 years (95% CI 4.64-9.15). The negative independent risk factors for OS were male gender, age above 70, metastases in LN at diagnosis, and no SLNB in patients without clinical nodal metastases. Our results confirm that the MCC treatment should be conducted in an experienced multidisciplinary team; however, the outcomes are still unsatisfactory.

6.
J Dermatolog Treat ; 33(4): 2168-2174, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34057374

RESUMO

BACKGROUND: The relationship between immune related adverse events (irAEs) and efficacy is not definitively proven, and data on the relationship between irAE and treatment efficacy are contradictory. MATERIAL AND METHODS: Five hundred ninety-three consecutive patients with unresectable or metastatic melanoma treated in the first line with anti-PD-1 (nivolumab or pembrolizumab) between January 2016 and December 2019 were enrolled in the study. RESULTS: Statistically significant differences were demonstrated between the group of patients without and with irAE in median OS and PFS (p < .0001 both) and also in OS between the group of patients without irAE and patients with irAE within 3, 6, and 9 months from the start of anti-PD-1 therapy (p = .0121, p = .0014, p < .0001; respectively) and PFS (p = .0369, p = .0052, p = .0001; respectively). A statistically significant relationship was demonstrated between the occurrence of irAE and the location of the primary tumor (skin vs. mucosa vs. unknown; p = .0183), brain metastasis (present vs. absent; p = .0032), other locations (present vs. absent, p = .0032), LDH (normal vs. elevated; p = .0046) and stage according to TNM (p = .0093). CONCLUSION: The occurrence of irAE was associated with longer OS, PFS, and more frequent response to treatment. IrAE occurred statistically significantly more often in patients with mucosa primary tumor, with normal LDH levels, without brain metastases, stages III, M1a, and M1b.


Assuntos
Melanoma , Nivolumabe , Humanos , Imunoterapia , Melanoma/tratamento farmacológico , Melanoma/patologia , Nivolumabe/efeitos adversos , Estudos Retrospectivos , Resultado do Tratamento
7.
Immunotherapy ; 13(4): 297-307, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33353420

RESUMO

Aim: To evaluate treatment results in advanced/metastatic melanoma patients treated with anti-PD-1 immunotherapy in routine practice in oncology centers in Poland. Methods: Multicenter retrospective analysis included 499 patients with unresectable/metastatic (stage IIIC-IV) melanoma treated with anti-PD-1 in first-line therapy. Results: Estimated median overall survival (OS) and progression-free survival (PFS) were 19.9 and 7.9 months, respectively. Multivariate analysis confirmed that ECOG 0, no brain metastases, normal lactate dehydrogenase level and occurrence of immune-related adverse events (irAEs) were statistically significantly associated with improved OS and PFS. Any irAE occurred in 24% of patients. Grade 3 or Grade 4 irAEs occurred in 6% of patients. Conclusion: Analysis revealed a slightly worse OS in real-world treatment in comparison to clinical trials (KEYNOTE-006 and CheckMate 066). Polish population treatment results are similar to other studies of real-world data. PFS and ORR are similar in our research and clinical trials.


Assuntos
Inibidores de Checkpoint Imunológico/uso terapêutico , Melanoma/tratamento farmacológico , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Monoclonais Humanizados/uso terapêutico , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Feminino , Humanos , Imunoterapia , Masculino , Melanoma/mortalidade , Melanoma/patologia , Pessoa de Meia-Idade , Nivolumabe/uso terapêutico , Polônia , Prognóstico , Intervalo Livre de Progressão , Estudos Retrospectivos , Taxa de Sobrevida , Resultado do Tratamento
8.
Endocrine ; 72(3): 893-904, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33244704

RESUMO

PURPOSE: Small intestinal neuroendocrine tumours (siNETs) with a Ki-67 proliferation index between 3 and 20% belong to WHO grade 2. Response to treatment may be monitored by blood chromogranin A (CgA) and urine 5-hydroxyindoleacetic acid (5HIAA). The aim of this retrospective study was to investigate the prognostic value of baseline CgA and 5HIAA and of the early biochemical response to treatment, and to compare different cut-off values used in the literature. METHODS: A retrospective cohort study of 184 patients with siNET Grade 2 treated with somatostatin analogues (SSA), interferon-alpha (IFN) or peptide receptor radionuclide therapy (PRRT). RESULTS: Baseline CgA was a statistically significant prognostic marker for both cancer-specific survival (CSS) and progression-free survival (PFS). A cut-off of 5 × ULN (upper limit of normal) was best discriminative in most cases, but 2 × ULN discriminated better for SSA. Baseline 5HIAA was a prognostic marker for CSS in treatment with IFN and PRRT, but not for single SSA. Early changes of CgA and 5HIAA correlated well with CSS (HR 3.18, 95% CI 1.82-5.56 and HR 1.47, 95% CI 1.16-1.86) and PFS (HR 3.08, 95% CI 1.86-5.10 and HR 1.37, 95% CI 1.11-1.68) for SSA, but not for PRRT. CONCLUSIONS: Baseline CgA and to a lesser extent 5HIAA are associated with CSS irrespective of treatment used, and with PFS after PRRT, and 5 × ULN provides best discrimination in many, but not all, cases. Early reductions of CgA and 5HIAA are prognostic for treatment with SSA, but not PRRT.


Assuntos
Neoplasias Intestinais , Tumores Neuroendócrinos , Cromogranina A , Humanos , Octreotida , Prognóstico , Estudos Retrospectivos
9.
Melanoma Res ; 31(1): 49-57, 2021 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-33165240

RESUMO

Immunotherapy with anti-programmed cell death-1 (PD-1) agents is an effective treatment for metastatic melanoma. Octogenarians and nonagenarians represent a significant cohort of melanoma patients. This multicenter retrospective analysis enrolled 499 patients treated with nivolumab or pembrolizumab. Seventy-three patients were aged 80-100, 218 patients were aged 65-79, and 208 patients were <65 years old. Baseline parameters were comparable. The median overall survival (OS) was 14.7, 18.7, 25.9, and the median progression-free survival (PFS) was 8.7, 7.7, and 6.2 months in the age groups of 80-100, 65-79, and <65 years, respectively. The median melanoma-specific survival (MSS) was 22.5, 27.8, and 31.6 months in the age groups of 80-100, 65-79, and <65 years, respectively. There was no statistically significant difference in OS (P = 0.2897), PFS (P = 0.7155), and MSS (P = 0.9235) between the group of 80-100 years old vs. 65-79 and vs. <65 years old patients. Overall response rate and disease control rate was similar in all groups (P = 0.06974 and P = 0.89435, respectively). Overall, the immune-related adverse event (irAE) rate was comparable in the three age groups (41, 34, and 37.5% in the groups of patients aged 80-100, 65-79, and <65 years, respectively). Also, the rates of G3 and G4 irAEs were comparable (4, 6, and 7% in the groups of patients, respectively). The efficacy and toxicity of anti-PD-1 therapy in octogenarians and nonagenarians with metastatic melanoma are similar as in patients aged <65 years and 65-79 years. The patients' age should not be considered as an exclusion criterion for anti-PD-1 treatment.


Assuntos
Melanoma/tratamento farmacológico , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Neoplasias Cutâneas/tratamento farmacológico , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Melanoma/patologia , Receptor de Morte Celular Programada 1/uso terapêutico , Neoplasias Cutâneas/patologia
10.
Oncotarget ; 8(61): 104149-104159, 2017 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-29262628

RESUMO

Lapatinib is a HER1 and HER2 tyrosine kinase inhibitor (TKI) approved in second line treatment of advanced or metastatic breast cancer following progression on trastuzumab-containing therapy. Biomarkers for activity of lapatinib and other TKIs are lacking. Formalin-fixed, paraffin-embedded primary tumor samples were obtained from 189 HER2-positive patients treated with lapatinib plus capecitabine following progression on trastuzumab. The HERmark® Breast Cancer Assay was used to quantify HER2 protein expression. HER3 and p95HER2 protein expression was quantified using the VeraTag® technology. Overall survival (OS) was inversely correlated with HER2 (HR = 1.9/log; P = 0.009) for patients with tumors above the cut-off positivity level by the HERmark assay. OS was significantly shorter for those with above median HER2 levels (HR = 1.7; P = 0.015) and trended shorter for those below the cut-off level of positivity by the HERmark assay (HR = 1.7; P = 0.057) compared to cases with moderate HER2 overexpression. The relationship between HER2 protein expression and OS was best captured with a U-shaped parabolic function (P = 0.004), with the best prognosis at moderate levels of HER2 protein overexpression. In a multivariate model including HER2, increasing p95HER2 expression was associated with longer OS (HR = 0.35/log; P = 0.027). Continuous HER3 did not significantly correlate with OS. Patients with moderately overexpressed HER2 levels and high p95HER2 expression may have best outcomes while receiving lapatinib following progression on trastuzumab. Further study is warranted to explore the predictive utility of quantitative HER2 and p95HER2 in guiding HER2-directed therapies.

11.
Mol Med Rep ; 14(3): 2548-54, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27485939

RESUMO

Photodynamic therapy (PDT) is a minimally invasive cancer treatment. It involves the combination of a photosensitizer and light of a specific wavelength to generate singlet oxygen and other reactive oxygen species that lead to tumor cell death. Autophagy is one of the pathways that tumor cells undergo during photodamage and it is common in photodynamic therapy. The aim of this study was to examine the effect of in vitro PDT on the expression of autophagy­related proteins, autophagy related 7 (Atg7), light chain 3 (LC3) and Beclin­1. Human SW620 colon carcinoma cells were treated with 5-aminolevulinic acid (ALA)­based PDT at a dose of 3 mM. The irradiation was performed using 4.5 J/cm2 total light and a fluence rate of 60 mW/cm2. Autophagy was evaluated by immunocytochemistry using specific antibodies to Atg7, Beclin­1 and LC3. The evaluation was repeated at several time points (0, 4, 8 and 24 h) following irradiation. The induction of autophagy was observed directly following the 5­ALA­mediated PDT procedure with the strongest expression of autophagy-related proteins at 4 and 8 h after irradiation as demonstrated using immunocytochemistry. It was characterized by significantly increased expression of Beclin­1, Atg7 and LC3. To the best of our knowledge this is the first study to analyze Beclin­1, Atg7 and LC3 expression in a PDT­related experiment. This study enhances the understanding of the role of autophagy in PDT, which may contribute to better and more effective tumor responses to this therapy.


Assuntos
Autofagia/genética , Regulação da Expressão Gênica , Adenocarcinoma , Autofagia/efeitos dos fármacos , Autofagia/efeitos da radiação , Biomarcadores , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/genética , Sobrevivência Celular/efeitos da radiação , Células Cultivadas , Neoplasias do Colo , Regulação da Expressão Gênica/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos da radiação , Humanos , Imuno-Histoquímica , Luz , Fotoquimioterapia , Fármacos Fotossensibilizantes/farmacologia
12.
Oncotarget ; 7(1): 550-64, 2016 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-26623720

RESUMO

UNLABELLED: Molecular mechanisms of lapatinib resistance in breast cancer are not well understood. The aim of this study was to correlate expression of selected proteins involved in ErbB family signaling pathways with clinical efficacy of lapatinib. Study group included 270 HER2-positive advanced breast cancer patients treated with lapatinib and capecitabine. Immunohistochemical expression of phosphorylated adenosine monophosphate-activated protein (p-AMPK), mitogen-activated protein kinase (p-MAPK), phospho (p)-p70S6K, cyclin E, phosphatase and tensin homolog were analyzed in primary breast cancer samples. The best discriminative value for progression-free survival (PFS) was established for each biomarker and subjected to multivariate analysis. At least one biomarker was determined in 199 patients. Expression of p-p70S6K was independently associated with longer (HR 0.45; 95% CI: 0.25-0.81; p = 0.009), and cyclin E with shorter PFS (HR 1.83; 95% CI: 1.06-3.14; p = 0.029). Expression of p-MAPK (HR 1.61; 95% CI 1.13-2.29; p = 0.009) and cyclin E (HR 2.99; 95% CI: 1.29-6.94; p = 0.011) was correlated with shorter, and expression of estrogen receptor (HR 0.65; 95% CI 0.43-0.98; p = 0.041) with longer overall survival. Expression of p-AMPK negatively impacted response to treatment (HR 3.31; 95% CI 1.48-7.44; p = 0.004) and disease control (HR 3.07; 95% CI 1.25-7.58; p = 0.015). IN CONCLUSION: the efficacy of lapatinib seems to be associated with the activity of downstream signaling pathways - AMPK/mTOR and Ras/Raf/MAPK. Further research is warranted to assess the clinical utility of these data and to determine a potential role of combining lapatinib with MAPK pathway inhibitors.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Imuno-Histoquímica/métodos , Quinazolinas/uso terapêutico , Receptor ErbB-2/antagonistas & inibidores , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Ciclina E/metabolismo , Feminino , Humanos , Estimativa de Kaplan-Meier , Lapatinib , Pessoa de Meia-Idade , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Avaliação de Resultados em Cuidados de Saúde/métodos , Avaliação de Resultados em Cuidados de Saúde/estatística & dados numéricos , Fosforilação/efeitos dos fármacos , Valor Preditivo dos Testes , Prognóstico , Modelos de Riscos Proporcionais , Inibidores de Proteínas Quinases/farmacologia , Receptor ErbB-2/metabolismo , Receptores de Estrogênio/metabolismo , Proteínas Quinases S6 Ribossômicas 70-kDa/metabolismo , Adulto Jovem
13.
J Neurosci Res ; 82(4): 563-70, 2005 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-16211563

RESUMO

Activity-regulated cytoskeleton-associated protein (Arc) is an effector immediate early gene product implicated in long-term potentiation and other forms of neuroplasticity. Earlier studies demonstrated Arc induction in discrete brain regions by several psychoactive substances, including drugs of abuse. In the present experiments, the influence of morphine on Arc expression was assessed by quantitative reverse transcription real-time PCR and Western blotting in vivo in the mouse striatum/nucleus accumbens and, in vitro, in the mouse Neuro2A MOR1A cell line, expressing mu-opioid receptor. An acute administration of morphine produced a marked increase in Arc mRNA and protein level in the mouse striatum/nucleus accumbens complex. After prolonged opiate treatment, tolerance to the stimulatory effect of morphine on Arc expression developed. No changes in the striatal Arc mRNA levels were observed during spontaneous or opioid antagonist-precipitated morphine withdrawal. In Neuro2A MOR1A cells, acute, but not prolonged, morphine treatment elevated Arc mRNA level by activation of mu-opioid receptor. This was accompanied by a corresponding increase in Arc protein level. Inhibition experiments revealed that morphine induced Arc expression in Neuro2A MOR1A cells via intracellular signaling pathways involving mitogen-activated protein (MAP) kinases and protein kinase C. These results lend further support to the notion that stimulation of opioid receptors may exert an activating influence on some intracellular pathways and leads to induction of immediate early genes. They also demonstrate that Arc is induced in the brain in vivo after morphine administration and thus may play a role in neuroadaptations produced by the drug.


Assuntos
Complexo Relacionado com a AIDS/metabolismo , Corpo Estriado/efeitos dos fármacos , Expressão Gênica/efeitos dos fármacos , Morfina/administração & dosagem , Entorpecentes/administração & dosagem , Receptores Opioides mu/metabolismo , Complexo Relacionado com a AIDS/genética , Análise de Variância , Animais , Western Blotting/métodos , Linhagem Celular Tumoral , Corpo Estriado/metabolismo , Relação Dose-Resposta a Droga , Esquema de Medicação , Interações Medicamentosas , Ala(2)-MePhe(4)-Gly(5)-Encefalina/farmacologia , Inibidores Enzimáticos/farmacologia , Flavonoides/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Regulação da Expressão Gênica/fisiologia , Indóis/farmacologia , Masculino , Maleimidas/farmacologia , Camundongos , Camundongos Endogâmicos C57BL , Neuroblastoma/metabolismo , RNA Mensageiro/biossíntese , Receptores Opioides mu/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Somatostatina/análogos & derivados , Somatostatina/farmacologia , Fatores de Tempo
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