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1.
BMC Cell Biol ; 16: 6, 2015 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-25886724

RESUMO

BACKGROUND: Mps1, an essential component of the mitotic checkpoint, is also an important interphase regulator and has roles in DNA damage response, cytokinesis and centrosome duplication. Mps1 predominantly resides in the cytoplasm and relocates into the nucleus at the late G2 phase. So far, the mechanism underlying the Mps1 translocation between the cytoplasm and nucleus has been unclear. RESULTS: In this work, a dynamic export process of Mps1 from the nucleus to cytoplasm in interphase was revealed- a process blocked by the Crm1 inhibitor, Leptomycin B, suggesting that export of Mps1 is Crm1 dependent. Consistent with this speculation, a direct association between Mps1 and Crm1 was found. Furthermore, a putative nuclear export sequence (pNES) motif at the N-terminal of Mps1 was identified by analyzing the motif of Mps1. This motif shows a high sequence similarity to the classic NES, a fusion of this motif with EGFP results in dramatic exclusion of the fusion protein from the nucleus. Additionally, Mps1 mutant loss of pNES integrity was shown by replacing leucine with alanine which produced a diffused subcellular distribution, compared to the wild type protein which resides predominantly in cytoplasm. CONCLUSION: Taken these findings together, it was concluded that the pNES sequence is sufficient for the Mps1 export from nucleus during interphase.


Assuntos
Proteínas de Ciclo Celular/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Tirosina Quinases/metabolismo , Transporte Ativo do Núcleo Celular/efeitos dos fármacos , Motivos de Aminoácidos , Proteínas de Ciclo Celular/química , Proteínas de Ciclo Celular/genética , Linhagem Celular Tumoral , Núcleo Celular/metabolismo , Citoplasma/metabolismo , Ácidos Graxos Insaturados/farmacologia , Células HEK293 , Humanos , Interfase , Carioferinas/antagonistas & inibidores , Carioferinas/metabolismo , Ligação Proteica , Proteínas Serina-Treonina Quinases/química , Proteínas Serina-Treonina Quinases/genética , Estrutura Secundária de Proteína , Estrutura Terciária de Proteína , Transporte Proteico/efeitos dos fármacos , Proteínas Tirosina Quinases/química , Proteínas Tirosina Quinases/genética , Receptores Citoplasmáticos e Nucleares/antagonistas & inibidores , Receptores Citoplasmáticos e Nucleares/metabolismo , Proteína Exportina 1
2.
Discov Oncol ; 15(1): 48, 2024 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-38403682

RESUMO

OBJECTIVE: To investigate the clinical features, treatment strategies, and prognosis of neuroblastoma with bilateral blindness. METHODS: The clinical data of five patients with bilateral blindness neuroblastoma admitted to Beijing Children's Hospital from April 2018 to September 2020 were retrospectively collected to summarize their clinical characteristics. RESULTS: All patients were female and the median age at presentation was 25 (23, 41) months. The median intervention time from the onset of symptoms of bilateral blindness to the start of treatment was 10 (10, 12) days. All five cases were staged as stage M and grouped as high risk. Four cases were MYCN gene amplification and one case was MYCN acquisition. Five children were treated according to a high-risk neuroblastoma treatment protocol. Four children did not recover their vision after treatment, and one case improved to have light perception. All patients were effectively followed up for a median of 20 (12, 31) months, with three deaths, one tumor-free survival, and one recurrent tumor-bearing survival. CONCLUSION: Neuroblastoma with bilateral blindness is rare in the clinic, mostly in children of young age, and is often associated with MYCN amplification and multiple metastases. Early hormone shock therapy and optic nerve decompression are beneficial for preserving the child's vision. A joint multi-disciplinary treatment may help in the formulation of treatment decisions. Achieving a balance between good visual preservation and survival within the short optic nerve neurotherapeutic window is extremely challenging.

3.
Front Nutr ; 9: 810485, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35308278

RESUMO

Household food consumption is the associative link between ecosystems and anthropogenic activities. In grassland areas, inappropriate food consumption patterns will cause irreversible damage to vulnerable local ecosystems. For this study, we selected three typical transitional grassland areas of Inner Mongolia, China (i.e., meadow steppe, typical steppe, and desert steppe), to analyze spatial heterogeneity in household food consumption and nutritional characteristics. Results showed that: (a) Food consumption structures exhibited zonal gradients from east to west alongside a reduction in grassland conditions. Additionally, the average food consumption quantity also decreased. Available food supplies altered household preferences for vegetables and fruits, meat, dairy products, and other food consumption category types. (b) The nutritional structure implied that grains provided the main source of energy, proteins, and fat for local rural households, while meat, dairy products, beans (including bean byproducts), and oils caused a fluctuation in the nutritional structure of residents. (c) Local food supplies affect short-term local food consumption patterns, while socioeconomic development affects long-term food consumption patterns. This study is intended to provide a reference for the development of sustainable strategies for regional resource management.

4.
Front Oncol ; 10: 1441, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32983973

RESUMO

The controversy of adjuvant radiotherapy of meningiomas is at least partially due to the insufficient understanding on meningioma cells' response to irradiation and the shortage of radiosensitivity-promotion methods. MicroRNA-221 and microRNA-222 were identified as critical regulators of radiosensitivity in several other tumors. However, their effect in meningiomas has yet to be confirmed. Therefore, the malignant meningioma IOMM-Lee cells were adopted, transfected with microRNA-221/222 mimics or inhibitors, and irradiated with different dosages. The effects of radiation and microRNA-221/222 were then assessed in vitro and in vivo. Radiation dose increases and microRNA-221/222 downregulation synergistically inhibited cell proliferation and colony formation, prevented xenograft tumor progression, and promoted apoptosis, but antagonistically regulated cell invasiveness. Pairwise comparisons revealed that only high-dose radiations (6 and 8 Gy) can significantly promote cell invasiveness in comparison with unirradiated counterparts. Further comparisons exhibited that downregulating the microRNA-221/222 expression can reverse this radiation-induced cell invasiveness to a level of untransfected and unirradiated cells only if cells were irradiated with no more than 6 Gy. In addition, this approach can promote IOMM-Lee's radiosensitivity. Meanwhile, we also detected that the dose rate of irradiation affects cell cycle distribution and cell apoptosis of IOMM-Lee. A high dose rate irradiation induces G0/G1 cell cycle arrest and apoptosis-promoting effect. Therefore, for malignant meningiomas, high-dose irradiation can facilitate cell invasiveness significantly. Downregulating the microRNA-221/222 level can reverse the radiation-induced cell invasiveness while enhancing the apoptosis-promoting and proliferation-inhibiting effects of radiation and promoting cell radiosensitivity.

5.
Nucl Med Biol ; 39(3): 437-42, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22172386

RESUMO

OBJECTIVE: We explored the clinical values of (11)C-choline ((11)C-CHO) PET in optimization of target volume delineation and treatment regimens in postoperative radiotherapy for brain gliomas. METHODS: Sixteen patients with the pathological confirmation of the diagnosis of gliomas prior to receiving radiotherapy (postoperative) were included, and on whom both MRI and CHO PET scans were performed at the same position for comparison of residual tumors with the two techniques. (11)C-CHO was used as the tracer in the PET scan. A plain T1-weighted, T2-weighted and contrast-enhanced T1-weighted imaging scans were performed in the MRI scan sequence. The gliomas' residual tumor volume was defined as the area with CHO-PET high-affinity uptake and metabolism (V(CHO)) and one with MRI T1-weighted imaging high signal intensity (V(Gd)), and was determined by a group of experienced professionals and clinicians. RESULTS: (1) In CHO-PET images, the tumor target volume, i.e., the highly metabolic area with a high concentration of isotopes (SUV 1.016-4.21) and the corresponding contralateral normal brain tissues (SUV0.1-0.62), was well contrasted, and the boundary between lesions and surrounding normal brain tissues was better defined compared with MRI and (18)F-FDG PET images. (2) For patients with brain gliomas of WHO Grade II, the SUV was 1.016-2.5; for those with WHO Grades III and IV, SUVs were >26-4.2. (3) Both CHO PET and MRI were positive for 10 patients and negative for 2 patients. The residual tumor consistency between these two studies was 75%. Four of the 10 CHO-PET-positive patients were negative on MRI scans. The maximum distance between V(Gd) and V(CHO) margins was 1.8 cm. (4) The gross tumor volumes (GTVs) and the ensuing treatment regimens were changed for 31.3% (5/16) of patients based on the CHO-PET high-affinity uptake and metabolism, in which the change rate was 80% (4/5), 14.3 % (1/7) and 0% (0/4) for patients with WHO Grade II III, and IV gliomas, respectively. CONCLUSION: Our data demonstrate that difference exists between CHO PET and MRI by which to judge and identify residual tumor for patients with brain gliomas. CHO PET is considered to be a supplementary diagnostic approach for MRI. Biological tumor target volume (BTV) displayed in the CHO PET images is useful in determining or delineating the radiotherapy target volume and making decisions in selecting treatment regimens. Tumor target volume may be defined more accurately and rationally when the CHO PET is combined with MRI.


Assuntos
Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/radioterapia , Colina , Glioma/diagnóstico por imagem , Glioma/radioterapia , Compostos Radiofarmacêuticos , Planejamento da Radioterapia Assistida por Computador/métodos , Adolescente , Adulto , Idoso , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/cirurgia , Radioisótopos de Carbono , Criança , Feminino , Seguimentos , Glioma/patologia , Glioma/cirurgia , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Neoplasia Residual , Tomografia por Emissão de Pósitrons/métodos , Carga Tumoral
6.
Sheng Wu Gong Cheng Xue Bao ; 26(3): 357-62, 2010 Mar.
Artigo em Zh | MEDLINE | ID: mdl-20518349

RESUMO

Epidermal growth factor receptor (EGFR) and its ligands (EGF and TGFalpha) are over-expressed in a variety of tumors. Immunization EGF-carrier protein inhibits tumor growth through abrogating binding of EGF to EGFR. Here, a chimeric protein of EGF and TGFalpha (E5T) was genetically fused to Staphylococcal enterotoxin A (SEA), a bacterial superantigenic protein which promotes humoral B cell response through enhancement of Ag-specific CD4 T cells activity. The resulted fusion proteins were expressed in Escherichia coli and purified though metal chelating affinity chromatography. Immunization of E5T-mSEA fusion protein in mice induced production of high titers antibodies, which recognize both EGF and TGFalpha. Anti- E5T-mSEA serum at dilution of 1:10 significantly inhibited growth of A431 cell lines but had little effect on 293T cell lines.


Assuntos
Vacinas Anticâncer/biossíntese , Enterotoxinas/biossíntese , Fator de Crescimento Epidérmico/biossíntese , Receptores ErbB/antagonistas & inibidores , Fator de Crescimento Transformador alfa/biossíntese , Sequência de Aminoácidos , Animais , Vacinas Anticâncer/imunologia , Linhagem Celular Tumoral , Enterotoxinas/genética , Fator de Crescimento Epidérmico/genética , Receptores ErbB/imunologia , Escherichia coli/genética , Escherichia coli/metabolismo , Humanos , Imunização , Camundongos , Camundongos Endogâmicos C57BL , Dados de Sequência Molecular , Distribuição Aleatória , Proteínas Recombinantes de Fusão/biossíntese , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/imunologia , Fator de Crescimento Transformador alfa/genética
7.
Ai Zheng ; 21(2): 167-70, 2002 Feb.
Artigo em Zh | MEDLINE | ID: mdl-12479068

RESUMO

BACKGROUND & OBJECTIVE: Multi-drug resistance(MDR) is the most important failing reason of tumor chemotherapy, the substance that P-glycoprotein(P-gp), glutathione S-transferase-pi(GST-pi), Topoisomerase II (Topo II) etc was the fundamental substances producing MDR. Gastric carcinoma is the relatively familiar malignancy, the report was relatively fewness that the expression of P-gp, GST-pi and Topo II by means of immunohistochemistry were associated with in the gastric carcinomas of previously untreated patients. This study was designed to investigate the expression and significance of P-gp, glutathione S-transferase-pi(GST-pi) and Topoisomerase II(Topo II) in gastric carcinomas. METHODS: Seventy-five human gastric carcinomas of previously untreated patients were studied for the expression of P-gp, GST-pi and Topo II by means of immunohistochemistry. RESULTS: The expression of P-gp, GST-pi and Topo II were 76.0%, 85.3% and 68.0% in gastric carcinoma tissues. There was no significant relationship between the expression levels and age, sex, location of tumor and depth of tumor invasion. Positive rate was higher in glandular-form carcinoma than that in mucoid carcinoma, signet-ring cell carcinoma and poorly differentiated carcinoma (P < 0.05). There was a significant relationship between the lymph node involvement and the higher expression of P-gp, GST-pi, lower expression of Topo II. CONCLUSION: There is a correlation between the expression of P-gp, GST-pi, Topo II and histologic subtypes, the expression may also related to the differentiation and metastasis of the gastric carcinomas.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/análise , DNA Topoisomerases Tipo II/análise , Glutationa Transferase/análise , Isoenzimas/análise , Neoplasias Gástricas/química , Adulto , Idoso , Feminino , Glutationa S-Transferase pi , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Neoplasias Gástricas/patologia
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