RESUMO
The oncogenic fusion protein promyelocytic leukemia/retinoic acid receptor alpha (PML/RARα) is critical for acute promyelocytic leukemia (APL). PML/RARα initiates APL by blocking the differentiation and increasing the self-renewal of leukemic cells. The standard clinical therapies all-trans retinoic acid (ATRA) and arsenic trioxide (ATO), which induce PML/RARα proteolysis, have dramatically improved the prognosis of APL patients. However, the emergence of mutations conferring resistance to ATRA and ATO has created challenges in the treatment of APL patients. Exploring pathways that modulate the oncogenic activity of PML/RARα could help develop novel therapeutic strategies for APL, particularly for drug-resistant APL. Herein, we demonstrated for the first time that palmitoylation of PML/RARα was a critical determinant of its oncogenic activity. PML/RARα palmitoylation was found to be catalyzed mainly by the palmitoyltransferase ZDHHC3. Mechanistically, ZDHHC3-mediated palmitoylation regulated the oncogenic transcriptional activity of PML/RARα and APL pathogenesis. The knockdown or overexpression of ZDHHC3 had respective effects on the expression of proliferation- and differentiation-related genes. Consistently, the depletion or inhibition of ZDHHC3 could significantly arrest the malignant progression of APL, particularly drug-resistant APL, whereas ZDHHC3 overexpression appeared to have a promoting effect on the malignant progression of APL. Thus, our study not only reveals palmitoylation as a novel regulatory mechanism that modulates PML/RARα oncogenic activity but also identifies ZDHHC3 as a potential therapeutic target for APL, including drug-resistant APL.
RESUMO
Despite more effective chemotherapy combined with limb-salvage surgery for the osteosarcoma treatment, survival rates for osteosarcoma patients have stagnated over the past three decades due to the poor prognosis. Osteosarcoma cancer stem cells (OSCs) are responsible for the growth and metastasis of osteosarcoma. The existence of OSCs offers a theoretical explanation for therapeutic failures including tumor recurrence, metastasis, and drug resistance. Understanding the pathways that regulate properties of OSCs may shed light on mechanisms that lead to osteosarcoma and suggest better modes of treatment. In this study, we showed that the expression level of Kruppel-like factor 4 (KLF4) is highly associated with human osteosarcoma cancer stemness. KLF4-overexpressed osteosarcoma cells displayed characteristics of OSCs: increased sphere-forming potential, enhanced levels of stemness-associated genes, great chemoresistance to adriamycin and CDDP, as well as more metastasis potential. Inversely, KLF4 knockdown could reduce colony formation in vitro and inhibit tumorigenesis in vivo, supporting an oncogenic role for KLF4 in osteosarcoma pathogenesis. Furthermore, KLF4 was shown to activate the p38 MAPK signaling pathway to promote cancer stemness. Altogether, our studies uncover an essential role for KLF4 in regulation of OSCs and identify KLF4-p38 MAPK axis as a potential therapeutic target for osteosarcoma treatment.
Assuntos
Fatores de Transcrição Kruppel-Like/genética , Células-Tronco Neoplásicas/metabolismo , Osteossarcoma/genética , Animais , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Humanos , Fator 4 Semelhante a Kruppel , Fatores de Transcrição Kruppel-Like/antagonistas & inibidores , Fatores de Transcrição Kruppel-Like/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Células-Tronco Neoplásicas/efeitos dos fármacos , Células-Tronco Neoplásicas/patologia , Osteossarcoma/tratamento farmacológico , Osteossarcoma/patologia , Fenótipo , RNA Interferente Pequeno/farmacologia , Células Tumorais Cultivadas , Proteínas Quinases p38 Ativadas por Mitógeno/antagonistas & inibidores , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismoRESUMO
At present,the function evaluation of health food containing Chinese materia medica is in lack of theoretical support of Chinese medicine,which can't reflect the function characteristics,dose-effect relationship and mechanism of functional food. What' s more,the evaluation technology of health food containing Chinese materia medica is relatively lagging behind and has been abolished now,which seriously restricts the development of health food containing Chinese materia medica industry. The proportion of health food containing Chinese materia medica with enhancing immune function is the highest among approved products,which is up to 30.33%. By collecting,analyzing and digging the current evaluation situation of enhancing immune function of health food containing Chinese materia medica,this paper has shown that there is no difference between health food containing Chinese materia medica evaluation and other functional food evaluation. What's more,there is a lack of characteristics of traditional Chinese medicine(TCM). The technological means including evaluation of immune active substances is under-developed and the immune cell evaluation needs to be refined and improved urgently,restricting the development of health food containing Chinese materia medica industry. Therefore,the evaluation of the enhanced immune function of health food containing Chinese materia medica should be guided by health-preserving theory in TCM,and based on the identification of TCM constitution for its claim of health function. With TCM theory and modern scientific technological means,a new evaluation model for immune function enhancement of health food containing Chinese materia medica is put forward to distinguish it from other functional food and traditional medicines. Formulation of the evaluation technology and technical specifications suitable for health food containing Chinese materia medica can fundamentally ensure the healthy,orderly,fast and sustainable development of health food containing Chinese materia medica industry.
Assuntos
Alimento Funcional , Materia Medica , Medicina Tradicional Chinesa , Humanos , Sistema Imunitário , Projetos de Pesquisa , TecnologiaRESUMO
With the development of social economy,people's demand for health services is growing rapidly. As health resource with Chinese characteristics,health food containing Chinese materia medica have broad prospect and great market space for development.However,at present,there are still many problems of health food containing Chinese materia media in the research,development,evaluation and market application. In addition,due to lack of theoretical support of traditional Chinese medicine(TCM) in the research and development of health food containing Chinese materia media,blurred boundaries between health food containing Chinese materia media and other health products as well as TCM are present,lacking of TCM characteristics. In the evaluation process of health food containing Chinese materia media,the construction of functional food laws,regulations and evaluation norms is relatively lagging behind,which can't meet the needs of health food containing Chinese materia media research and development,severely restricting the development of health food containing Chinese materia media. Based on the research and evaluation of health food containing Chinese materia media,the existing problems were reviewed and the reasons for the deficiencies were analyzed in this paper. Guided by the theory of TCM,based on the constitution identification in TCM,and combined with modern scientific and technological means,a new research and development mode of functional food was put forward in this paper to distinguish health food containing Chinese materia media from TCM as well as general health products. Nevertheless,we should ensure the vitality of Chinese medicine health products with original thinking and scientific and technological connotations,and accelerate the harmonious,rapid and sustainable development of Chinese medicine health industry.
Assuntos
Alimento Funcional , Materia Medica , Medicina Tradicional Chinesa , Indústrias , PesquisaRESUMO
BACKGROUND: Artificial selection played an important role in the origin of modern Glycine max cultivars from the wild soybean Glycine soja. To elucidate the consequences of artificial selection accompanying the domestication and modern improvement of soybean, 25 new and 30 published whole-genome re-sequencing accessions, which represent wild, domesticated landrace, and Chinese elite soybean populations were analyzed. RESULTS: A total of 5,102,244 single nucleotide polymorphisms (SNPs) and 707,969 insertion/deletions were identified. Among the SNPs detected, 25.5% were not described previously. We found that artificial selection during domestication led to more pronounced reduction in the genetic diversity of soybean than the switch from landraces to elite cultivars. Only a small proportion (2.99%) of the whole genomic regions appear to be affected by artificial selection for preferred agricultural traits. The selection regions were not distributed randomly or uniformly throughout the genome. Instead, clusters of selection hotspots in certain genomic regions were observed. Moreover, a set of candidate genes (4.38% of the total annotated genes) significantly affected by selection underlying soybean domestication and genetic improvement were identified. CONCLUSIONS: Given the uniqueness of the soybean germplasm sequenced, this study drew a clear picture of human-mediated evolution of the soybean genomes. The genomic resources and information provided by this study would also facilitate the discovery of genes/loci underlying agronomically important traits.
Assuntos
Genoma de Planta , Glycine max/genética , Teorema de Bayes , Cruzamento , Evolução Molecular , Genética Populacional , Haplótipos , Humanos , Mutação INDEL , Anotação de Sequência Molecular , Filogenia , Polimorfismo de Nucleotídeo Único , Locos de Características Quantitativas , Seleção Genética , Análise de Sequência de DNARESUMO
A new concept for wound therapy is the initiation of the regeneration of epidermal and dermal layers with appendages for skin function recovery. Bone-marrow-derived mesenchymal and epidermal stem cells (BMSCs and SSCs) are hypothesized to be able to home toward or to be transplanted to wound sites for skin repair and regeneration, but this awaits confirmation by further experimental and clinical evidence. In this study, the influence of the transplantation of BMSCs and SSCs with porous gelatin-ß-tricalcium phosphate sponge as scaffolds on wound re-epithelization, collagen synthesis, skin tensile strength recovery, and skin appendage regeneration has been investigated. The transplantation of BMSCs or SSCs significantly accelerates wound re-epithelization, stimulates dermal collagen synthesis, and exhibits the trend to enhance the tensile strength recovery of skin. Furthermore, regenerative features of BMSCs and SSCs have been identified in activating blood vessel and hair follicle formation, respectively. These results not only provide experimental evidence for the application of BMSCs and SSCs as promising therapeutics for clinical wound treatment, but also display their characteristics in activating distinct skin appendage regeneration, which might have novel applications in skin tissue engineering.
Assuntos
Células da Medula Óssea/citologia , Células Epidérmicas , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais/citologia , Regeneração/fisiologia , Cicatrização , Animais , Células da Medula Óssea/efeitos dos fármacos , Células da Medula Óssea/metabolismo , Fosfatos de Cálcio/farmacologia , Separação Celular , Forma Celular/efeitos dos fármacos , Imuno-Histoquímica , Masculino , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Mesenquimais/metabolismo , Microscopia Eletrônica de Varredura , Molécula-1 de Adesão Celular Endotelial a Plaquetas/metabolismo , Ratos , Ratos Sprague-Dawley , Coloração e Rotulagem , Resistência à Tração/efeitos dos fármacos , Cicatrização/efeitos dos fármacosRESUMO
The success of gene therapy largely relies on a safe and effective gene delivery system. The objective of this study is to design a highly efficient system for the transfection of epidermal stem cells (ESCs) and investigate the transfected ESCs (TESCs) as a therapeutic agent and gene delivery reservoir for wound treatment. As a nonviral vector, ß-cyclodextrin-linked polyethylenimines (CYD-PEI) was synthesized by linking ß-cyclodextrin with polyethylenimines (600 Da). Gelatin scaffold incorporating ß-tricalcium phosphate (ß-TCP) was utilized as a substrate for the culture and transfection of ESCs. With the CYD-PEI/pDNA-VEGF165 polyplexes incorporated gelatin/ß-TCP scaffold based 3D transfection system, prolonged VEGF expression with a higher level was obtained at day 7 in ESCs than those in two-dimensional plates. Topical application of the TESCs significantly accelerated the skin re-epithelization, dermal collagen synthesis, and hair follicle regeneration. It also exhibited a potential in scar inhibition by regulating the distribution of different types of collagen. In contrast to ESCs, an additive capacity in stimulating angiogenesis at the wound site was observed in the TESCs. The present study provides a basis for the TESCs as a promising therapeutic agent and gene delivery reservoir for wound therapy.
Assuntos
Fosfatos de Cálcio/química , Células Epidérmicas , Gelatina/química , Polietilenoimina/química , Células-Tronco/metabolismo , Fator A de Crescimento do Endotélio Vascular/genética , Cicatrização/efeitos da radiação , beta-Ciclodextrinas/química , Animais , Células Cultivadas , Técnicas de Transferência de Genes , Terapia Genética , Nanopartículas/química , Ratos , Ratos Sprague-Dawley , Células-Tronco/citologia , Células-Tronco/fisiologia , Cicatrização/fisiologiaRESUMO
Runoff pollution control is currently a difficult problem in urban water environment protection. The identification of runoff pollution risk into rivers is the key to improve the efficiency of pollution control. By combining landscape patterns and processes and using the landscape pattern index and minimum cumulative resistance model, a set of integrated methods for river rainfall-runoff pollution risk identification and optimization was proposed. The rainfall-runoff pollution pattern, process, and comprehensive risk index of the major river reaches in the study area were calculated. The risk paths of runoff pollution generated by cultivated land, urban construction land, and traffic industrial and mining land were identified as 256, 182, and 208, respectively. The results showed that:â according to the pattern factors, a ten-level rainfall runoff pollution pattern risk index was identified, and more rivers in the central and southern regions had a relatively high pollution risk. â¡ The risk of runoff pollution caused by fragmentation and dominance factors was higher than that caused by aggregation factors, and the range was wider. The corresponding landscape pattern optimization methods were proposed for the three types of indicators. ⢠For the pollution process, the identified ten levels of rainfall runoff pollution process risk index showed that the rivers with high risk index were mainly concentrated in the central urban area and gradually decreased to the periphery. ⣠The range and intensity of rainfall and runoff pollution caused by different types of land use were as follows:in terms of range, cultivated land>traffic industrial and mining land>urban construction land. Regarding intensity, traffic industrial and mining land>urban construction land>cultivated land. ⤠The river pollution risk in the middle and southeast of the study area was significantly higher than that in the west and north of the study area. Among them, there were 13 level 1 risk reaches with a length of 209.65 km, accounting for 9.39% of the total length. There were 11 level 2 risk river sections with a length of 186.83 km, accounting for 8.37% of the total length. These river reaches should be the focus of urban rainfall runoff pollution control in the future.
Assuntos
Movimentos da Água , Poluentes Químicos da Água , China , Monitoramento Ambiental , Poluição Ambiental , Rios , Poluentes Químicos da Água/análiseRESUMO
Chitinases are digestive enzymes that break down glycosidic bonds in chitin. In the current study, an endochitinase gene Lbchi31 was cloned from Limonium bicolor. The cDNA sequence of Lbchi31 was 1,107 bp in length, encoding 322 amino acid residues with a calculated molecular mass of 31.7 kDa. Clustal analysis showed that there was a highly conserved chitin-binding domains in Lbchi31 protein, containing four sulfide bridges. The Lbchi31 gene was inserted into the pPIC9 vector and transferred into yeast Pichia pastoris GS115 and KM71 for heterologous expression. The transformant harboring the Lbchi31 gene showed a clearly visible protein band with a molecular mass of more than 31 kDa in the SDS-PAGE gel, indicating that it had been translated in P. pastoris. Enzyme characterization showed that the optimal reaction condition for chitinase LbCHI31 activity was: 40 degrees C, pH of 5.0 and 5 mmol l(-1) of Mn(2+). The maximum enzyme activity was 0.88 U ml(-1) following exposure to the cell wall chitin of Valsa sordida. The LbCHI31 enzyme can efficiently degrade cell wall chitin of the phytopathogenic Rhizoctonia solani, Fusarium oxysporum, Sclerotinia sclerotiorum, V. sordida, Septoria tritici and Phytophthora sojae, suggesting that it has the biocontrol function to fungal phytopathogen.
Assuntos
Quitinases/genética , Quitinases/metabolismo , Genes de Plantas/genética , Plumbaginaceae/enzimologia , Plumbaginaceae/genética , Sequência de Aminoácidos , Quitinases/química , Clonagem Molecular , Eletroforese em Gel de Poliacrilamida , Metais/farmacologia , Dados de Sequência Molecular , Pichia/efeitos dos fármacos , Pichia/metabolismo , Plumbaginaceae/efeitos dos fármacos , Proteínas Recombinantes/metabolismo , Análise de Sequência de DNA , Especificidade por Substrato/efeitos dos fármacos , TemperaturaRESUMO
In the present study, an endochitinase gene, Lbchi32, was cloned from Limonium bicolor. The cDNA sequence of Lbchi32 was 1,443 bp in length and encoded 319 amino acid residues. The DNA sequence of Lbchi32 was 2,512 bp in length and contained three exons and two introns. The Lbchi32 gene was inserted into a pPIC9 vector and transferred into Pichia pastoris strains GS115 and KM71 for heterologous expression. SDS-PAGE analyses indicated that LbCHI32 was expressed in both GS115 and KM71 and that it was secreted extracellularly. The optimal reaction conditions for LbCHI32 activity are 45 degrees C, pH 5.0, and 5 mM Ba(2+). The LbCHI32 enzyme can efficiently degrade chitin, chitin derivatives, and the cell walls of different pathogenic fungi, including phytopathogenic Rhizoctonia solani, Fusarium oxysporum, Sclerotinia sclerotiorum, Valsa sordida, Septoria tritici, and Phytophthora sojae. These findings suggest that Lbchi32 has potential use in the degradation of chitin and chitin derivatives.
Assuntos
Quitinases/genética , Quitinases/metabolismo , Genes de Plantas/genética , Plumbaginaceae/enzimologia , Plumbaginaceae/genética , Sequência de Aminoácidos , Biocatálise/efeitos dos fármacos , Quitinases/química , Clonagem Molecular , Eletroforese em Gel de Poliacrilamida , Metais/farmacologia , Dados de Sequência Molecular , Pichia/metabolismo , Plumbaginaceae/efeitos dos fármacos , Proteínas Recombinantes/metabolismo , Análise de Sequência de DNA , Especificidade por Substrato/efeitos dos fármacosRESUMO
Osteosarcoma is the most common primary malignant bone tumour, but the survival rate of patients has plateaued since the mid-1980s. Adriamycin is an integral component of the current first-line chemotherapies used for osteosarcoma, but dose-dependent severe side effects often limit its clinical application. Here, we propose a potential combination regimen in which adriamycin plus 2-bromopalmitate, a palmitoylation inhibitor, exhibited powerful therapeutic effects on osteosarcoma. First, 2-bromopalmitate strongly increased the proliferation inhibition of adriamycin in both human osteosarcoma cell lines and primary osteosarcoma cells. Adriamycin-induced apoptosis in osteosarcoma cells was enhanced when synergized with 2-bromopalmitate. Our study indicated that the reactive oxygen species scavenger NAC and GSH could largely reverse the apoptosis induced by adriamycin combined with 2-bromopalmitate, demonstrating that reactive oxygen species played an essential role in this combination therapy. Moreover, CHOP was remarkably elevated in the combination group, and silencing of CHOP almost completely blocked the apoptosis induced by the combination of 2-bromopalmitate and adriamycin. Taken together, our study provides a prospective therapeutic strategy to eliminate osteosarcoma, which is propitious to clinical combination therapy development.