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1.
Sci Rep ; 14(1): 11073, 2024 05 14.
Artigo em Inglês | MEDLINE | ID: mdl-38744888

RESUMO

To investigate the ability of an auxiliary diagnostic model based on the YOLO-v7-based model in the classification of cervical lymphadenopathy images and compare its performance against qualitative visual evaluation by experienced radiologists. Three types of lymph nodes were sampled randomly but not uniformly. The dataset was randomly divided into for training, validation, and testing. The model was constructed with PyTorch. It was trained and weighting parameters were tuned on the validation set. Diagnostic performance was compared with that of the radiologists on the testing set. The mAP of the model was 96.4% at the 50% intersection-over-union threshold. The accuracy values of it were 0.962 for benign lymph nodes, 0.982 for lymphomas, and 0.960 for metastatic lymph nodes. The precision values of it were 0.928 for benign lymph nodes, 0.975 for lymphomas, and 0.927 for metastatic lymph nodes. The accuracy values of radiologists were 0.659 for benign lymph nodes, 0.836 for lymphomas, and 0.580 for metastatic lymph nodes. The precision values of radiologists were 0.478 for benign lymph nodes, 0.329 for lymphomas, and 0.596 for metastatic lymph nodes. The model effectively classifies lymphadenopathies from ultrasound images and outperforms qualitative visual evaluation by experienced radiologists in differential diagnosis.


Assuntos
Linfonodos , Linfoma , Humanos , Linfoma/diagnóstico , Linfoma/patologia , Linfoma/diagnóstico por imagem , Feminino , Linfonodos/patologia , Linfonodos/diagnóstico por imagem , Pessoa de Meia-Idade , Masculino , Adulto , Linfadenopatia/diagnóstico , Linfadenopatia/patologia , Ultrassonografia/métodos , Idoso , Metástase Linfática
2.
Sci Rep ; 14(1): 37, 2024 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-38167455

RESUMO

Diagnosing low-grade and high-grade endometrial stromal sarcoma (LG-ESS and HG-ESS) is a challenge. This study aimed to identify biomarkers. 22 ESS cases were analyzed using Illumina microarrays. Differentially expressed genes (DEGs) were identified via Limma. DEGs were analyzed with String and Cytoscape. Core genes were enriched with GO and KEGG, their pan-cancer implications and immune aspects were studied. 413 DEGs were found by exome sequencing, 2174 by GSE85383 microarray. 36 common genes were identified by Venn analysis, and 10 core genes including RBFOX1, PCDH7, FAT1 were selected. Core gene GO enrichment included cell adhesion, T cell proliferation, and KEGG focused on related pathways. Expression was evaluated across 34 cancers, identifying immune DEGs IGF1 and AVPR1A. Identifying the DEGs not only helps improve our understanding of LG-ESS, HG-ESS but also promises to be potential biomarkers for differential diagnosis between LG-ESS and HG-ESS and new therapeutic targets.


Assuntos
Neoplasias do Endométrio , Sarcoma do Estroma Endometrial , Feminino , Humanos , Sarcoma do Estroma Endometrial/diagnóstico , Sarcoma do Estroma Endometrial/genética , Biomarcadores Tumorais/metabolismo , Perfilação da Expressão Gênica , Neoplasias do Endométrio/diagnóstico , Neoplasias do Endométrio/genética , Biologia Computacional
3.
Ultrasound Q ; 40(1): 39-45, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-37545088

RESUMO

ABSTRACT: The objective of this study is to develop and validate the performance of 2 ultrasound (US) feature-guided machine learning models in distinguishing cervical lymphadenopathy. We enrolled 705 patients whose US characteristics of lymph nodes were collected at our hospital. B-mode US and color Doppler US features of cervical lymph nodes in both cohorts were analyzed by 2 radiologists. The decision tree and back propagation (BP) neural network were developed by combining clinical data (age, sex, and history of tumor) and US features. The performance of the 2 models was evaluated by calculating the area under the receiver operating characteristics curve (AUC), accuracy value, precision value, recall value, and balanced F score (F1 score). The AUC of the decision tree and BP model in the modeling cohort were 0.796 (0.757, 0.835) and 0.854 (0.756, 0.952), respectively. The AUC, accuracy value, precision value, recall value, and F1 score of the decision tree in the validation cohort were all higher than those of the BP model: 0.817 (0.786, 0.848) vs 0.674 (0.601, 0.747), 0.774 (0.737, 0.811) vs 0.702 (0.629, 0.775), 0.786 (0.739, 0.833) vs 0.644 (0.568, 0.720), 0.733 (0.694, 0.772) vs 0.630 (0.542, 0.718), and 0.750 (0.705, 0.795) vs 0.627 (0.541, 0.713), respectively. The US feature-guided decision tree model was more efficient in the diagnosis of cervical lymphadenopathy than the BP model.


Assuntos
Linfadenopatia , Humanos , Estudos Retrospectivos , Linfadenopatia/diagnóstico , Ultrassonografia , Linfonodos/diagnóstico por imagem , Linfonodos/patologia , Aprendizado de Máquina
4.
Eur J Cancer Prev ; 32(5): 450-459, 2023 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-37038992

RESUMO

OBJECTIVE: Cytochrome P450 1B1 ( CYP1B1 ) genetic variants are relevant in the pathogenesis of breast cancer. Exploring the relationships between CYP1B1 functional variants and breast cancer could improve our understanding of breast cancer molecular pathophysiology. METHODS: This is a two-stage hospital-based case-control study of a Chinese Han population. Genotyping was performed to identify candidate gene variants. 3DSNP, ANNOVAR, and RegulomeDB were used to determine functional single nucleotide polymorphisms (SNPs). The relationship between candidate variants and breast cancer risk was evaluated through unconditional logistic regression analysis. The PancanQTL platform was used to perform cis and trans expression quantitative trait loci (eQTL) analysis of positive SNPs. The GSCA platform was then used to compare the gene expression levels of potential target genes between breast cancer tissue and normal tissue adjacent to the cancer. RESULTS: rs10175368-T acted as a protective factor against breast cancer based on an additive model [odds ratio (OR) = 0.722, 95% confidence interval (CI) = 0.613-0.850; P < 0.001], and was identified as a protective factor in the postmenopausal population (OR = 0.601; 95% CI, 0.474-0.764; P < 0.001). eQTL analysis and analysis of differential expression in carcinoma and paracancerous tissues revealed that the expression level of CYP1B1 - AS1 was associated with rs10175368 and that CYP1B1-AS1 had significantly higher expression levels in breast cancer tissues than in paracancerous tissues. CONCLUSION: We show, for the first time in a Chinese Han population, that the functional variant rs10175368 plays a protective role against breast cancer, especially in the postmenopausal population.


Assuntos
Neoplasias da Mama , Humanos , Feminino , Neoplasias da Mama/genética , Neoplasias da Mama/prevenção & controle , Estudos de Casos e Controles , População do Leste Asiático , Polimorfismo de Nucleotídeo Único , Risco , Predisposição Genética para Doença , Genótipo , Fatores de Risco , Citocromo P-450 CYP1B1/genética
5.
Chemosphere ; 310: 136767, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36241112

RESUMO

Cyanobacterial blooms negatively affect aquatic ecosystems and human health. Algicidal bacteria can efficiently kill bloom-causing cyanobacteria. Bacillus altitudinis G3 isolated from Dianchi Lake shows high algicidal activity against Microcystis aeruginosa. In this study, we investigated its algicidal characteristics including attack mode, photosynthesis responses, and source and the contribution of reactive oxygen species (ROS). The results showed that G3 efficiently and specifically killed M. aeruginosa mainly by releasing both thermolabile and thermostable algicidal substances, which exhibited the highest algicidal activity (99.8%, 72 h) in bacterial mid-logarithmic growth phase. The algicidal ratio under full-light conditions (99.5%, 60 h) was significantly higher than under dark conditions (<20%, P < 0.001). G3 filtrate caused photosystem dysfunction by decreasing photosynthetic efficiency, as indicated by significantly decreased Fv/Fm and PIABS (P < 0.001) values. It also inhibited photosynthetic electron transfer as indicated by significantly decreased rETR (P < 0.001), especially QA- downstream, as revealed by significantly decreased φEo and ψo, and increased Mo (P < 0.001). These results indicated that the algicidal activity of G3 filtrate is light-dependent, and the cyanobacterial photosystem is an important target. Cyanobacterial ROS and malondialdehyde contents greatly increased by 37.1% and 208% at 36 h, respectively. ROS levels decreased by 49.2% (9 h) when diuron (3-(3-4-dichlorophenyl)-1,1-dimethylurea) partially blocked photosynthetic electron transport from QA to QB. Therefore, excessive ROS were produced from disrupted photosynthesis, especially the inhibited electron transport area in QA- downstream, and caused severe lipid peroxidation with significantly increased MDA content and oxidative stress in cyanobacteria. The ROS scavenger N-acetyl-l-cysteine significantly decreased both cyanobacterial ROS levels (34%) and algicidal ratio (52%, P < 0.05) at 39 h. Thus, excessive ROS production due to G3 filtrate administration significantly contributed to its algicidal effect. G3 could be an excellent algicide to control M. aeruginosa blooms in waters under suitable light conditions.


Assuntos
Bacillus , Microcystis , Humanos , Espécies Reativas de Oxigênio/farmacologia , Ecossistema , Proliferação Nociva de Algas
6.
Plant Genome ; 15(1): e20193, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35102721

RESUMO

Many wild-relative species are being used in prebreeding programs to increase the genetic diversity of wheat (Triticum aestivum L.). Genotyping tools such as single nucleotide polymorphism (SNP)-based arrays and molecular markers have been widely used to characterize wheat-wild relative introgression lines. However, due to the polyploid nature of the recipient wheat genome, it is difficult to develop SNP-based Kompetitive allele-specific polymerase chain reaction (KASP) markers that are codominant to track the introgressions from the wild species. Previous attempts to develop KASP markers have involved both exome- and polymerase chain reaction (PCR)-amplicon-based sequencing of the wild species. But chromosome-specific KASP assays have been hindered by homoeologous SNPs within the wheat genome. This study involved whole genome sequencing of the diploid wheat wild relative Amblyopyrum muticum (Boiss.) Eig and development of a de novo SNP discovery pipeline that generated ∼38,000 SNPs in unique wheat genome sequences. New assays were designed to increase the density of Am. muticum polymorphic KASP markers. With a goal of one marker per 60 Mbp, 335 new KASP assays were validated as diagnostic for Am. muticum in a wheat background. Together with assays validated in previous studies, 498 well distributed chromosome-specific markers were used to recharacterize previously genotyped wheat-Am. muticum doubled haploid (DH) introgression lines. The chromosome-specific nature of the KASP markers allowed clarification of which wheat chromosomes were involved with recombination events or substituted with Am. muticum chromosomes and the higher density of markers allowed detection of new small introgressions in these DH lines.


Assuntos
Poaceae , Triticum , Alelos , Cromossomos , Marcadores Genéticos , Poaceae/genética , Reação em Cadeia da Polimerase , Triticum/genética
7.
Sci Total Environ ; 806(Pt 4): 150719, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-34606873

RESUMO

Cyanobacterial blooms significantly decrease water quality and can damage ecosystems and, as such, require efficient control methods. Algicidal bacteria and their associated substances are promising tools for controlling cyanobacterial blooms; however, their specific algicidal mechanisms remain unclear. Therefore, the current study sought to investigate the algicidal mechanism of tryptoline (1,2,3,4-tetrahydro-9 h-pyrido[3,4-b]indole) against Microcystis aeruginosa, with a specific focus on the contribution made by reactive oxygen species (ROS), the underlying mechanisms of ROS increase, as well as the photosystem response. Results show that the algicidal ratio of tryptoline significantly and positively correlates with algal ROS. Moreover, 93.79% of the algicidal ratio variation is attributed to ROS in the tryptoline group, while only 47.75% can be attributed to ROS in the tryptoline + N-acetyl-L-cysteine (NAC) group, where ROS are partially scavenged by NAC. In the presence of tryptoline, algicidal effect and ROS levels were significantly enhanced in the presence of light as compared to those in the dark (P < 0.001). Hence, the increase in ROS production attributed to tryptoline is primarily affected by the presence of light and photosynthesis. Additionally, tryptoline significantly reduces Fv/Fm, PIABS, ETo/RC, and the expression of psaB and psbA genes related to photosynthesis, while increasing Vj and DIo/RC (P < 0.05). These results suggest that tryptoline hinders algal photosynthesis by significantly decreasing photosynthetic efficiency and carbon assimilation, inhibiting photochemical electron transfer, and increasing closed reaction centers and energy loss. Moreover, following partial blockade of the photosynthetic electron transfer from QA to QB by diuron (3-(3-4-dichlorophenyl)-1,1-dimethylurea), the ROS of algae exposed to tryptoline is significantly decreased. Thus, tryptoline inhibits electron transfer downstream of QA, which increase the number of escaping electron and thereby increase ROS generation. Collectively, this study describes the algicidal mechanism of tryptoline against M. aeruginosa and highlights the critical factors associated with induction of algicidal activity.


Assuntos
Microcystis , Carbolinas , Ecossistema , Proliferação Nociva de Algas , Fotossíntese , Espécies Reativas de Oxigênio
8.
AMB Express ; 10(1): 136, 2020 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-32748086

RESUMO

Antroquinonol (AQ) has several remarkable bioactivities in acute myeloid leukaemia and pancreatic cancer, but difficulties in the mass production of AQ hamper its applications. Currently, molecular biotechnology methods, such as gene overexpression, have been widely used to increase the production of metabolites. However, AQ biosynthetic genes and enzymes are poorly understood. In this study, an integrated study coupling RNA-Seq and isobaric tags for relative and absolute quantitation (iTRAQ) were used to identify AQ synthesis-related genes and enzymes in Antrodia camphorata during coenzyme Q0-induced fermentation (FM). The upregulated genes related to acetyl-CoA synthesis indicated that acetyl-CoA enters the mevalonate pathway to form the farnesyl tail precursor of AQ. The metE gene for an enzyme with methyl transfer activity provided sufficient methyl groups for AQ structure formation. The CoQ2 and ubiA genes encode p-hydroxybenzoate polyprenyl transferase, linking coenzyme Q0 and the polyisoprene side chain to form coenzyme Q3. NADH is transformed into NAD+ and releases two electrons, which may be beneficial for the conversion of coenzyme Q3 to AQ. Understanding the biosynthetic genes and enzymes of AQ is important for improving its production by genetic means in the future.

9.
Chemosphere ; 249: 126097, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32078851

RESUMO

Benz(a)anthracene (BaA) is a polycyclic aromatic hydrocarbons (PAHs), that belongs to a group of carcinogenic and mutagenic persistent organic pollutants found in a variety of ecological habitats. In this study, the efficient biodegradation of BaA by a green alga Chlamydomonas reinhardtii (C. reinhardtii) CC-503 was investigated. The results showed that the growth of C. reinhardtii was hardly affected with an initial concentration of 10 mg/L, but was inhibited significantly under higher concentrations of BaA (>30 mg/L) (p < 0.05). We demonstrated that the relatively high concentration of 10 mg/L BaA was degraded completely in 11 days, which indicated that C. reinhardtii had an efficient degradation system. During the degradation, the intermediate metabolites were determined to be isomeric phenanthrene or anthracene, 2,6-diisopropylnaphthalene, 1,3-diisopropylnaphthalene, 1,7-diisopropylnaphthalene, and cyclohexanol. The enzymes involved in the degradation included the homogentisate 1,2-dioxygenase (HGD), the carboxymethylenebutenolidase, the ribulose 1,5-bisphosphate carboxylase/oxygenase (Rubisco) and the ubiquinol oxidase. The respective genes encoding these proteins were significantly up-regulated ranging from 3.17 fold to 13.03 fold and the activity of enzymes, such as HGD and Rubisco, was significantly induced up to 4.53 and 1.46 fold (p < 0.05), during the BaA metabolism. This efficient degradation ability suggests that the green alga C. reinhardtii CC-503 may be a sustainable candidate for PAHs remediation.


Assuntos
Antracenos/metabolismo , Biodegradação Ambiental , Chlamydomonas reinhardtii/metabolismo , Poluentes Ambientais/metabolismo , Benzo(a)Antracenos/metabolismo , Carcinógenos/metabolismo , Dioxigenases/metabolismo , Fenantrenos , Hidrocarbonetos Policíclicos Aromáticos/metabolismo
10.
Plant Biotechnol J ; 18(3): 743-755, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31465620

RESUMO

For future food security, it is important that wheat, one of the most widely consumed crops in the world, can survive the threat of abiotic and biotic stresses. New genetic variation is currently being introduced into wheat through introgressions from its wild relatives. For trait discovery, it is necessary that each introgression is homozygous and hence stable. Breeding programmes rely on efficient genotyping platforms for marker-assisted selection (MAS). Recently, single nucleotide polymorphism (SNP)-based markers have been made available on high-throughput Axiom® SNP genotyping arrays. However, these arrays are inflexible in their design and sample numbers, making their use unsuitable for long-term MAS. SNPs can potentially be converted into Kompetitive allele-specific PCR (KASP™) assays that are comparatively cost-effective and efficient for low-density genotyping of introgression lines. However, due to the polyploid nature of wheat, KASP assays for homoeologous SNPs can have difficulty in distinguishing between heterozygous and homozygous hybrid lines in a backcross population. To identify co-dominant SNPs, that can differentiate between heterozygotes and homozygotes, we PCR-amplified and sequenced genomic DNA from potential single-copy regions of the wheat genome and compared them to orthologous copies from different wild relatives. A panel of 620 chromosome-specific KASP assays have been developed that allow rapid detection of wild relative segments and provide information on their homozygosity and site of introgression in the wheat genome. A set of 90 chromosome-nonspecific assays was also produced that can be used for genotyping introgression lines. These multipurpose KASP assays represent a powerful tool for wheat breeders worldwide.


Assuntos
Mapeamento Cromossômico , Homozigoto , Melhoramento Vegetal , Triticum/genética , Cromossomos de Plantas/genética , Genótipo , Polimorfismo de Nucleotídeo Único
11.
BMC Plant Biol ; 19(1): 183, 2019 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-31060503

RESUMO

BACKGROUND: Triticum timopheevii (2n = 4x = 28; AtAtGG), is an important source for new genetic variation for wheat improvement with genes for potential disease resistance and salt tolerance. By generating a range of interspecific hybrid lines, T. timopheevii can contribute to wheat's narrow gene-pool and be practically utilised in wheat breeding programmes. Previous studies that have generated such introgression lines between wheat and its wild relatives have been unable to use high-throughput methods to detect the presence of wild relative segments in such lines. RESULTS: A whole genome introgression approach, exploiting homoeologous recombination in the absence of the Ph1 locus, has resulted in the transfer of different chromosome segments from both the At and G genomes of T. timopheevii into wheat. These introgressions have been detected and characterised using single nucleotide polymorphism (SNP) markers present on a high-throughput Axiom® Genotyping Array. The analysis of these interspecific hybrid lines has resulted in the detection of 276 putative unique introgressions from T. timopheevii, thereby allowing the generation of a genetic map of T. timopheevii containing 1582 SNP markers, spread across 14 linkage groups representing each of the seven chromosomes of the At and G genomes of T. timopheevii. The genotyping of the hybrid lines was validated through fluorescence in situ hybridisation (FISH). Comparative analysis of the genetic map of T. timopheevii and the physical map of the hexaploid wheat genome showed that synteny between the two species is highly conserved at the macro-level and confirmed the presence of inter- and intra-genomic translocations within the At and G genomes of T. timopheevii that have been previously only detected through cytological techniques. CONCLUSIONS: In this work, we report a set of SNP markers present on a high-throughput genotyping array, able to detect the presence of T. timopheevii in a hexaploid wheat background making it a potentially valuable tool for marker assisted selection (MAS) in wheat pre-breeding programs. These valuable resources of high-density molecular markers and wheat-T. timopheevii hybrid lines will greatly enhance the work being undertaken for wheat improvement through wild relative introgressions.


Assuntos
Genoma de Planta , Hibridização Genética , Poliploidia , Triticum/genética , Mapeamento Cromossômico , Cromossomos de Plantas/genética , Cruzamentos Genéticos , Ecótipo , Ligação Genética , Loci Gênicos , Marcadores Genéticos , Genótipo , Polimorfismo de Nucleotídeo Único/genética , Recombinação Genética/genética , Sementes/genética , Especificidade da Espécie
12.
Cancer Commun (Lond) ; 38(1): 49, 2018 07 25.
Artigo em Inglês | MEDLINE | ID: mdl-30045759

RESUMO

BACKGROUND: Induced pluripotent stem cells (iPSCs) and embryonic stem cells (ESCs) share many common features, including similar morphology, gene expression and in vitro differentiation profiles. However, genomic stability is much lower in iPSCs than in ESCs. In the current study, we examined whether changes in DNA damage repair in iPSCs are responsible for their greater tendency towards mutagenesis. METHODS: Mouse iPSCs, ESCs and embryonic fibroblasts were exposed to ionizing radiation (4 Gy) to introduce double-strand DNA breaks. At 4 h later, fidelity of DNA damage repair was assessed using whole-genome re-sequencing. We also analyzed genomic stability in mice derived from iPSCs versus ESCs. RESULTS: In comparison to ESCs and embryonic fibroblasts, iPSCs had lower DNA damage repair capacity, more somatic mutations and short indels after irradiation. iPSCs showed greater non-homologous end joining DNA repair and less homologous recombination DNA repair. Mice derived from iPSCs had lower DNA damage repair capacity than ESC-derived mice as well as C57 control mice. CONCLUSIONS: The relatively low genomic stability of iPSCs and their high rate of tumorigenesis in vivo appear to be due, at least in part, to low fidelity of DNA damage repair.


Assuntos
Dano ao DNA , Reparo do DNA por Junção de Extremidades/genética , Instabilidade Genômica/genética , Células-Tronco Pluripotentes Induzidas/metabolismo , Animais , Células Cultivadas , Quebras de DNA de Cadeia Dupla/efeitos da radiação , Embrião de Mamíferos/citologia , Feminino , Fibroblastos/citologia , Fibroblastos/metabolismo , Fibroblastos/efeitos da radiação , Expressão Gênica/efeitos da radiação , Instabilidade Genômica/efeitos da radiação , Células-Tronco Pluripotentes Induzidas/citologia , Células-Tronco Pluripotentes Induzidas/efeitos da radiação , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Células-Tronco Embrionárias Murinas/citologia , Células-Tronco Embrionárias Murinas/metabolismo , Células-Tronco Embrionárias Murinas/efeitos da radiação , Radiação Ionizante
13.
Chin J Cancer Res ; 30(1): 40-50, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29545718

RESUMO

OBJECTIVE: To develop and validate a radiomics prediction model for individualized prediction of perineural invasion (PNI) in colorectal cancer (CRC). METHODS: After computed tomography (CT) radiomics features extraction, a radiomics signature was constructed in derivation cohort (346 CRC patients). A prediction model was developed to integrate the radiomics signature and clinical candidate predictors [age, sex, tumor location, and carcinoembryonic antigen (CEA) level]. Apparent prediction performance was assessed. After internal validation, independent temporal validation (separate from the cohort used to build the model) was then conducted in 217 CRC patients. The final model was converted to an easy-to-use nomogram. RESULTS: The developed radiomics nomogram that integrated the radiomics signature and CEA level showed good calibration and discrimination performance [Harrell's concordance index (c-index): 0.817; 95% confidence interval (95% CI): 0.811-0.823]. Application of the nomogram in validation cohort gave a comparable calibration and discrimination (c-index: 0.803; 95% CI: 0.794-0.812). CONCLUSIONS: Integrating the radiomics signature and CEA level into a radiomics prediction model enables easy and effective risk assessment of PNI in CRC. This stratification of patients according to their PNI status may provide a basis for individualized auxiliary treatment.

14.
Epigenomics ; 10(6): 765-783, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29480027

RESUMO

AIM: Cancer stem cells (CSCs) drive triple-negative breast cancer recurrence via their properties of self-renewal, invasiveness and radio/chemotherapy resistance. This study examined how CSCs might sustain these properties. MATERIALS & METHODS: Transcriptomes, DNA methylomes and histone modifications were compared between CSCs and non CSCs. RESULTS: Transcriptome analysis revealed several pathways that were activated in CSCs, whereas cell cycle regulation pathways were inhibited. Cell development and signaling genes were differentially methylated, with histone methylation analysis suggesting distinct H3K4me2 and H3K27me3 enrichment profiles. An integrated analysis revealed several tumor suppressor genes downregulated in CSCs. CONCLUSION: Differential activation of various signaling pathways and genes contributes to the tumor-promoting properties of CSCs. Therapeutic targets identified in the analysis may contribute to improving treatment options for patients.


Assuntos
Neoplasias da Mama/genética , DNA/metabolismo , Regulação Neoplásica da Expressão Gênica , Histonas/metabolismo , Células-Tronco Neoplásicas/metabolismo , Neoplasias da Mama/metabolismo , Linhagem Celular Tumoral , Epigênese Genética , Feminino , Humanos , Metilação , Transcriptoma
15.
Biochem Biophys Res Commun ; 493(1): 643-649, 2017 11 04.
Artigo em Inglês | MEDLINE | ID: mdl-28865962

RESUMO

There is an intimate connection between mitochondrial DNA (mtDNA) methylation and some diseases, such as cancer. MtDNA is almost strictly maternally inherited. However, whether the aberrant mtDNA methylation involved in breast cancer progression and whether mtDNA methylation can be transmitted through maternal line are poorly understood. Here we applied bisulfite sequencing to global mitochondrial DNA and whole genomic DNA methylation array from fifteen members of five three-female-generation families with one breast cancer patient in each family. We found that mtDNA methylation was maternally inherited in D-loop region and eight aberrant mtDNA methylation sites were correlated with breast cancer. Furthermore, conjoint analysis showed that mtDNA methylation sites could be potential biomarkers combined with nuclear DNA methylation sites for breast cancer risk prediction.


Assuntos
Neoplasias da Mama/genética , Metilação de DNA/genética , DNA Mitocondrial/genética , Predisposição Genética para Doença/genética , Genoma Humano/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , China , Feminino , Humanos , Pessoa de Meia-Idade
16.
Nanotechnology ; 28(4): 045704, 2017 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-27981952

RESUMO

Magnetoferritin (M-HFn) is a biomimetic magnetic nanoparticle with a human heavy-chain ferritin (HFn) shell, trapping a magnetite (Fe3O4) core that has inherited peroxidase-like activity. In this study, cobalt-doped M-HFn nanoparticles (M-HFn-Co x Fe3-x O4) with different amounts of cobalt were successfully synthesized. Experimental results indicate that the controlled doping of a certain amount of cobalt into the magnetite cores of M-HFn nanoparticles enhances its peroxidase-like catalytic activity and efficacy for visualizing tumour tissues. For example, compared with sample Co0 (without cobalt doping), the peroxidase-like activity of the cobalt-doped nanoparticle sample Co60 (with a cobalt doping molar percentage of ∼34.2%) increases 1.7 times, and has the maximal reaction velocity (V max) values. Moreover, after a one-step incubation with Co60 nanoparticles, and using the peroxidase substrate 3,3'-diaminobenzidine tetrahydrochloride (DAB) for colour development, the tumour tissues of breast, colorectal, stomach and pancreas tumours showed a deeper brown colour with clear boundaries between the healthy and tumourous cells. Therefore, this suggests that the cobalt-doped magnetoferritin nanoparticles enhance peroxidase activity and tumour tissue visualization.

17.
IEEE Trans Med Imaging ; 35(1): 337-53, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26336121

RESUMO

The accurate segmentation of lung lesions from computed tomography (CT) scans is important for lung cancer research and can offer valuable information for clinical diagnosis and treatment. However, it is challenging to achieve a fully automatic lesion detection and segmentation with acceptable accuracy due to the heterogeneity of lung lesions. Here, we propose a novel toboggan based growing automatic segmentation approach (TBGA) with a three-step framework, which are automatic initial seed point selection, multi-constraints 3D lesion extraction and the final lesion refinement. The new approach does not require any human interaction or training dataset for lesion detection, yet it can provide a high lesion detection sensitivity (96.35%) and a comparable segmentation accuracy with manual segmentation (P > 0.05), which was proved by a series assessments using the LIDC-IDRI dataset (850 lesions) and in-house clinical dataset (121 lesions). We also compared TBGA with commonly used level set and skeleton graph cut methods, respectively. The results indicated a significant improvement of segmentation accuracy . Furthermore, the average time consumption for one lesion segmentation was under 8 s using our new method. In conclusion, we believe that the novel TBGA can achieve robust, efficient and accurate lung lesion segmentation in CT images automatically.


Assuntos
Algoritmos , Processamento de Imagem Assistida por Computador/métodos , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/patologia , Tomografia Computadorizada por Raios X/métodos , Bases de Dados Factuais , Humanos
18.
Oncotarget ; 6(38): 40611-21, 2015 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-26485765

RESUMO

As a diagnostic biomarker, prostate special antigen (PSA) tests always generate false positive results and lead to unnecessary and/or repeat biopsies. Therefore, there is an urgent need for developing more sensitive, specific diagnostic biomarkers. We epigenotyped methylated sites in cancer tissues and adjacent normal tissues from 66 patients. In comparison with normal adjacent tissues, we observed that there were 6 aberrant methylation sites in prostate cancer tissues on the Y-chromosome. We further performed pyrosequencing using urine of PCa patients and we identified one methylated site (cg05163709) as a potential biomarker. We evaluated the predictive capacity of the aberrant methylated sites using the area under receiver operating characteristic (ROC) curve (AUC). The ROC analysis showed a higher AUC for cg05163709 (0.915) than prostate-specific antigen (PSA, 0.769). These results indicated that aberrant DNA methylation of cg05163709 on the Y-chromosome could serve as a potential diagnostic biomarker with high sensitivity and specificity.


Assuntos
Biomarcadores Tumorais/genética , Cromossomos Humanos Y/genética , Metilação de DNA , Polimorfismo de Nucleotídeo Único/genética , Neoplasias da Próstata/diagnóstico , Neoplasias da Próstata/genética , Idoso , Idoso de 80 Anos ou mais , Imunoprecipitação da Cromatina , Humanos , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Estadiamento de Neoplasias , Prognóstico , Antígeno Prostático Específico/sangue , Neoplasias da Próstata/sangue , Curva ROC , Reação em Cadeia da Polimerase em Tempo Real
19.
Inf Process Med Imaging ; 24: 588-99, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26221705

RESUMO

We investigate the problem of diagnostic lung nodule classification using thoracic Computed Tomography (CT) screening. Unlike traditional studies primarily relying on nodule segmentation for regional analysis, we tackle a more challenging problem on directly modelling raw nodule patches without any prior definition of nodule morphology. We propose a hierarchical learning framework--Multi-scale Convolutional Neural Networks (MCNN)--to capture nodule heterogeneity by extracting discriminative features from alternatingly stacked layers. In particular, to sufficiently quantify nodule characteristics, our framework utilizes multi-scale nodule patches to learn a set of class-specific features simultaneously by concatenating response neuron activations obtained at the last layer from each input scale. We evaluate the proposed method on CT images from Lung Image Database Consortium and Image Database Resource Initiative (LIDC-IDRI), where both lung nodule screening and nodule annotations are provided. Experimental results demonstrate the effectiveness of our method on classifying malignant and benign nodules without nodule segmentation.


Assuntos
Neoplasias Pulmonares/diagnóstico por imagem , Redes Neurais de Computação , Reconhecimento Automatizado de Padrão/métodos , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Nódulo Pulmonar Solitário/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Algoritmos , Humanos , Intensificação de Imagem Radiográfica/métodos , Radiografia Torácica/métodos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
20.
Int J Nanomedicine ; 10: 2619-34, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25878496

RESUMO

PURPOSE: This study is to demonstrate the nanoscale size effect of ferrimagnetic H-ferritin (M-HFn) nanoparticles on magnetic properties, relaxivity, enzyme mimetic activities, and application in magnetic resonance imaging (MRI) and immunohistochemical staining of cancer cells. MATERIALS AND METHODS: M-HFn nanoparticles with different sizes of magnetite cores in the range of 2.7-5.3 nm were synthesized through loading different amounts of iron into recombinant human H chain ferritin (HFn) shells. Core size, crystallinity, and magnetic properties of those M-HFn nanoparticles were analyzed by transmission electron microscope and low-temperature magnetic measurements. The MDA-MB-231 cancer cells were incubated with synthesized M-HFn nanoparticles for 24 hours in Dulbecco's Modified Eagle's Medium. In vitro MRI of cell pellets after M-HFn labeling was performed at 7 T. Iron uptake of cells was analyzed by Prussian blue staining and inductively coupled plasma mass spectrometry. Immunohistochemical staining by using the peroxidase-like activity of M-HFn nanoparticles was carried out on MDA-MB-231 tumor tissue paraffin sections. RESULTS: The saturation magnetization (M(s)), relaxivity, and peroxidase-like activity of synthesized M-HFn nanoparticles were monotonously increased with the size of ferrimagnetic cores. The M-HFn nanoparticles with the largest core size of 5.3 nm exhibit the strongest saturation magnetization, the highest peroxidase activity in immunohistochemical staining, and the highest r2 of 321 mM(-1) s(-1), allowing to detect MDA-MB-231 breast cancer cells as low as 10(4) cells mL(-1). CONCLUSION: The magnetic properties, relaxivity, and peroxidase-like activity of M-HFn nanoparticles are size dependent, which indicates that M-HFn nanoparticles with larger magnetite core can significantly enhance performance in MRI and staining of cancer cells.


Assuntos
Imageamento por Ressonância Magnética/métodos , Nanopartículas de Magnetita/química , Neoplasias , Coloração e Rotulagem/métodos , Linhagem Celular Tumoral , Humanos , Neoplasias/química , Neoplasias/metabolismo , Tamanho da Partícula
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