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1.
Int J Hyperthermia ; 41(1): 2335201, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38583875

RESUMO

PURPOSE: Radiotherapy (RT) is the primary treatment for prostate cancer (PCa); however, the emergence of castration-resistant prostate cancer (CRPC) often leads to treatment failure and cancer-related deaths. In this study, we aimed to explore the use of microwave hyperthermia (MW-HT) to sensitize PCa to RT and investigate the underlying molecular mechanisms. METHODS: We developed a dedicated MW-HT heating setup, created an in vitro and in vivo MW-HT + RT treatment model for CRPC. We evaluated PC3 cell proliferation using CCK-8, colony experiments, DAPI staining, comet assay and ROS detection method. We also monitored nude mouse models of PCa during treatment, measured tumor weight, and calculated the tumor inhibition rate. Western blotting was used to detect DNA damage repair protein expression in PC3 cells and transplanted tumors. RESULTS: Compared to control, PC3 cell survival and clone formation rates decreased in RT + MW-HT group, demonstrating significant increase in apoptosis, ROS levels, and DNA damage. Lower tumor volumes and weights were observed in treatment groups. Ki-67 expression level was reduced in all treatment groups, with significant decrease in RT + MW-HT groups. The most significant apoptosis induction was confirmed in RT + MW-HT group by TUNEL staining. Protein expression levels of DNA-PKcs, ATM, ATR, and P53/P21 signaling pathways significantly decreased in RT + MW-HT groups. CONCLUSION: MW-HT + RT treatment significantly inhibited DNA damage repair by downregulating DNA-PKcs, ATM, ATR, and P53/P21 signaling pathways, leading to increased ROS levels, aggravate DNA damage, apoptosis, and necrosis in PC3 cells, a well-established model of CRPC.


Assuntos
Adenocarcinoma , Hipertermia Induzida , Neoplasias de Próstata Resistentes à Castração , Neoplasias da Próstata , Humanos , Masculino , Animais , Camundongos , Neoplasias de Próstata Resistentes à Castração/radioterapia , Neoplasias de Próstata Resistentes à Castração/metabolismo , Células PC-3 , Espécies Reativas de Oxigênio/metabolismo , Micro-Ondas , Proteína Supressora de Tumor p53/metabolismo , Hipertermia Induzida/métodos , Neoplasias da Próstata/radioterapia , Neoplasias da Próstata/metabolismo , Reparo do DNA , Apoptose , Estresse Oxidativo , Hipertermia , Adenocarcinoma/radioterapia , DNA/metabolismo , Linhagem Celular Tumoral , Proliferação de Células
2.
J Gene Med ; 26(1): e3579, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37581210

RESUMO

BACKGROUND: The involvement of ferroptosis has been found in many pathological conditions of the lung. The genetic engineering of ferroptosis-related genes may provide a potential target for the treatment of lung adenocarcinoma (LUAD). METHODS: Nine ferroptosis regulators and markers were collected from FerrDb and their somatic mutations and expressions were analyzed based on The Cancer Genome Atlas (TCGA)-LUAD cohort data. Least absolute shrinkage and selection operator (LASSO) and Cox regression analysis were performed to screen genes significantly associated with ferroptosis. The ferroptosis-related gene signature was constructed using TCGA-LUAD cohort data and was verified using the GSE cohort with pooled data for GSE30219, GSE31210, GSE37745 and GSE50081. Immune microenvironment component and mutation analysis were performed for genes in the ferroptosis-related gene signature. RESULTS: All nine ferroptosis regulators and markers were differentially expressed between normal LUAD tumor tissues and adjacent normal tissues and were related to copy number variation. The expression of 1329 genes were significantly associated with nine ferroptosis regulators and markers in the TCGA-LUAD dataset, five (ALDOA, PLK1, CD47, CENPC and TMOD3) of which were integrated into a ferroptosis-related gene signature to calculate the risk score of LUAD samples, showing a significant correlation with the abundance of immune cell infiltration and the immune score. Molecular docking showed the binding activity of natural active compound quercetin to target proteins ALDOA and CD47, as well as the binding activity of aristolochic acid to PLK1 protein and TMOD3 protein. CONCLUSIONS: In the present study, a ferroptosis-related gene signature with predictive value for LUAD prognosis was constructed, in which the gene was a potential therapeutic target for LUAD. Quercetin and aristolochic acid were potential candidates for inhibiting these targets by directly binding to them and showing high affinity and strong stability.


Assuntos
Adenocarcinoma de Pulmão , Ácidos Aristolóquicos , Ferroptose , Neoplasias Pulmonares , Humanos , Antígeno CD47 , Variações do Número de Cópias de DNA , Ferroptose/genética , Simulação de Acoplamento Molecular , Quercetina , Adenocarcinoma de Pulmão/tratamento farmacológico , Adenocarcinoma de Pulmão/genética , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Proteínas do Citoesqueleto , Microambiente Tumoral
3.
Mitochondrial DNA B Resour ; 8(12): 1421-1425, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38130729

RESUMO

Ludwigia adscendens (L.) Hara, 1953 (L. adscendens) belongs to the family Onagraceae, which is a traditional medicinal plant distributed worldwide. In this study, the first complete chloroplast genome of L. adscendens was sequenced and assembled. The assembled chloroplast genome of L. adscendens is 159,560 bp in length, containing a pair of inverted repeat region A (IRA) of 24,762 bp, inverted repeat region B (IRB) of 24,762 bp, separated by a large single-copy (LSC) sequence of 90,276 bp and a small single-copy (SSC) region of 19, 760 bp, respectively. A total of 129 genes were annotated in the entire chloroplast genome, consisting of 37 transfer RNA (tRNA) genes, 8 ribosomal RNA (rRNA) genes, and 84 protein-coding genes, with a total GC content of 37.27%. The phylogenomic analysis showed that L. adscendens was closely related to L. octovalvis in the Onagraceae family. Further evolutionary studies of the genus Ludwigia could benefit from the complete chloroplast genome of L. adscendens present in this study and the obtained results would provide useful information for future phylogenetic, taxonomic, and evolutionary studies on Onagraceae.

4.
Front Endocrinol (Lausanne) ; 14: 1179161, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37396169

RESUMO

Diabetic nephropathy (DN) is one of the most common and intractable microvascular complications of diabetes worldwide, serving as the main cause of terminal renal disease. Due to the lack of early specific symptoms and diagnostic markers, DN severely threatens the sufferer's life. MicroRNA-192 (miR-192) was early identified in human renal cortical tissue and stored and excreted in urine as microvesicles. MiR-192 was found to be involved in the development of DN. For the first time, the present review summarized all the current evidence on the topic of the roles of miR-192 in DN. Finally, 28 studies (ten clinical trials and eighteen experimental studies) were eligible for thorough reviewing. Most of the clinical trials (7/10, 70%) indicated miR-192 might be a protective factor for DN development and progression, while the majority of experimental studies (14/18, 78%) suggested miR-192 might be a pathogenic factor for DN. Mechanistically, miR-192 interacts with various direct targeted proteins (i.e., ZEB1, ZEB2, SIP1, GLP1R, and Egr1) and signaling cascades (i.e., SMAD/TGF-ß and PTEN/PI3K/AKT), together contribute to the pathogenesis of DN through epithelial-to-mesenchymal transition (EMT), extracellular matrix deposition, and fibrosis formation. The current review highlights the dual role of miR-192 in the development of DN. Low serum miR-192 expression could be applied for the early prediction of DN (the early stage of DN), while the high miR-192 level in renal tissues and urine may imply the progression of DN (the late stage of DN). Further investigations are still warranted to illustrate this inconsistent phenomenon, which may facilitate promoting the therapeutic applications of miR-192 in predicting and treating DN.


Assuntos
Diabetes Mellitus , Nefropatias Diabéticas , MicroRNAs , Humanos , Nefropatias Diabéticas/genética , Nefropatias Diabéticas/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Transdução de Sinais/genética , Matriz Extracelular/metabolismo , Diabetes Mellitus/metabolismo
5.
Food Sci Nutr ; 11(7): 4233-4245, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37457170

RESUMO

The hard-shelled mussel (Mytilus coruscus) has been used as a traditional Chinese medicine and health food in China for centuries. Polysaccharides from mussel has been reported to have multiple biological functions, however, it remains unclear whether mussel polysaccharide (MP) exerts protective effects in intestinal functions, and the underlying mechanisms of action remain unclear. The aim of this study was to investigate the protective effects and mechanism of MP on intestinal oxidative injury in mice. In this study, 40 male BALB/C mice were used, with 30 utilized to produce an animal model of intestinal oxidative injury with intraperitoneal injection of cyclophosphamide (Cy) for four consecutive days. The protective effects of two different doses of MP (300 and 600 mg/kg) were assessed by investigating the change in body weight, visceral index, and observing colon histomorphology. Moreover, the underlying molecular mechanisms were investigated by measuring the antioxidant enzymes and related signaling molecules through ELISA, real-time PCR, and western blot methods. The results showed that MP pretreatment effectively protected the intestinal from Cy-induced injury: improved the colon tissue morphology and villus structure, increased superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GSH-Px) activities, and reduced malondialdehyde (MDA) content in serum and colon tissues. Meanwhile, MP also significantly increased the expression levels of SOD, GSH-Px, heme oxygenase-1 (HO-1), and nuclear factor E2-related factor 2 (Nrf2) mRNA in colon tissues. Further, western blot results showed that the expression of Nrf2 protein was significantly upregulated while kelch-like ECH-associated protein 1 (Keap1) was significantly downregulated by MP in the colonic tissues. This study indicates that MP can ameliorate Cy-induced oxidative stress injury in mice, and Nrf2-Keap1 signaling pathway may mediate these protective effects.

6.
J Microbiol Biol Educ ; 24(1)2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37089227

RESUMO

The 2019 coronavirus disease pandemic and distrust for popular media have highlighted the need for effective methods of direct communication of biomedical science to the public. It is presently unclear how well nonexperts can learn from primary scientific sources and what factors predict such learning in the general public. The present study examined three modalities for learning about biomedical science directly from study investigators: primary scientific articles, annotated primary scientific articles presented online with interactive learning features, and TEDTalks about scientific studies presented by a study investigator. Each modality presented the same study, "Sleep Drives Metabolite Clearance from the Adult Brain" (L. Xie, H. Kang, Q. Chen, Y. Liao, et al., Science 342:373-377, 2013, https://doi.org/10.1126/science.1241224). Knowledge about the study's scientific content was assessed before and after the randomly assigned learning modality using multiple-choice questions. Participants included a sample of college psychology students and a sample of community-dwelling older adults. Cognitive tests were used to assess individual differences in working memory, processing speed, science literacy, and semantic knowledge. Surveys were used to assess trust in science and scientists, attitudes toward science, and attitudes toward cognitive tasks. Results indicated that both younger and older adults can learn basic biomedical science from a primary source. Knowledge gains were observed in all three learning modalities with no evidence of age group differences. Notably, the largest learning gains for undergraduates and older adults were observed in the primary scientific article condition, followed by the TEDTalk, and the annotated paper. Baseline knowledge about the science study topic and adoption of "scientific attitudes" (e.g., open-mindedness) predicted learning across age groups and learning modalities. These findings suggest that science educators, communicators, and outreach professionals should consider methods of promoting science literacy in the general public through direct access to primary scientific sources.

7.
Int. microbiol ; 25(3): 457-469, Ago. 2022. ilus
Artigo em Inglês | IBECS | ID: ibc-216206

RESUMO

Tangxun Lake is the largest urban lake in China, which is polluted by multiple wastewaters, and now is severely eutrophic. We detected diversity, abundance, and the coexistence of Candidatus Methylomirabilis oxyfera-like and anammox bacteria in different horizontal and vertical directions of the lake sediments through qPCR and clone library. Phylogenetic tree analysis showed that the Ca. Methylomirabilis oxyfera-like and anammox bacteria exhibited high diversity, and they belonged to group B—E and Ca. Brocadia genus, respectively. These two bacteria displayed higher diversity in polluted area than in other areas. Furthermore, they had great spatial variation of abundance both horizontally and vertically. The abundance of anammox bacteria was significantly higher than that of Ca. Methylomirabilis oxyfera-like bacteria. The stronger the human interference were, the higher abundances these two bacteria exhibited horizontally, whereas both their abundances and the ratio of anammox to Ca. Methylomirabilis oxyfera-like bacteria decreased with the increasing depth. Redundancy analysis indicated that nitrate was the most influential environmental factor to the abundance of these two bacteria. Ammonia, nitrite, total nitrogen, and organic matters were in positive correlation with the abundance of these two bacteria. Nitrate was slightly negatively correlated with the abundance of Ca. Methylomirabilis oxyfera-like bacteria, while it was positively correlated with that of anammox bacteria. Our results provided an insight into the effects of environmental factors such as ammonia, nitrite, and nitrate on the diversity and abundances of these two bacteria and theoretical basis for restoration of water.(AU)


Assuntos
Humanos , Águas Residuárias/microbiologia , Microbiologia da Água , Bactérias , Nitratos , Sedimentos , Microbiologia , China
8.
Int Microbiol ; 25(3): 457-469, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35094192

RESUMO

Tangxun Lake is the largest urban lake in China, which is polluted by multiple wastewaters, and now is severely eutrophic. We detected diversity, abundance, and the coexistence of Candidatus Methylomirabilis oxyfera-like and anammox bacteria in different horizontal and vertical directions of the lake sediments through qPCR and clone library. Phylogenetic tree analysis showed that the Ca. Methylomirabilis oxyfera-like and anammox bacteria exhibited high diversity, and they belonged to group B-E and Ca. Brocadia genus, respectively. These two bacteria displayed higher diversity in polluted area than in other areas. Furthermore, they had great spatial variation of abundance both horizontally and vertically. The abundance of anammox bacteria was significantly higher than that of Ca. Methylomirabilis oxyfera-like bacteria. The stronger the human interference were, the higher abundances these two bacteria exhibited horizontally, whereas both their abundances and the ratio of anammox to Ca. Methylomirabilis oxyfera-like bacteria decreased with the increasing depth. Redundancy analysis indicated that nitrate was the most influential environmental factor to the abundance of these two bacteria. Ammonia, nitrite, total nitrogen, and organic matters were in positive correlation with the abundance of these two bacteria. Nitrate was slightly negatively correlated with the abundance of Ca. Methylomirabilis oxyfera-like bacteria, while it was positively correlated with that of anammox bacteria. Our results provided an insight into the effects of environmental factors such as ammonia, nitrite, and nitrate on the diversity and abundances of these two bacteria and theoretical basis for restoration of water.


Assuntos
Lagos , Nitritos , Amônia , Oxidação Anaeróbia da Amônia , Anaerobiose , Bactérias/genética , Humanos , Metano , Nitratos , Oxirredução , Filogenia , RNA Ribossômico 16S/genética
9.
Hepatology ; 75(5): 1169-1180, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-34580885

RESUMO

BACKGROUND AND AIMS: Lipoprotein lipase (LPL) is responsible for the lipolytic processing of triglyceride-rich lipoproteins, the deficiency of which causes severe hypertriglyceridemia. Liver LPL expression is high in suckling rodents but relatively low at adulthood. However, the regulatory mechanism and functional significance of liver LPL expression are incompletely understood. We have established the zinc finger protein ZBTB20 as a critical factor for hepatic lipogenesis. Here, we evaluated the role of ZBTB20 in regulating liver Lpl gene transcription and plasma triglyceride metabolism. APPROACH AND RESULTS: Hepatocyte-specific inactivation of ZBTB20 in mice led to a remarkable increase in LPL expression at the mRNA and protein levels in adult liver, in which LPL protein was mainly localized onto sinusoidal epithelial cells and Kupffer cells. As a result, the LPL activity in postheparin plasma was substantially increased, and postprandial plasma triglyceride clearance was significantly enhanced, whereas plasma triglyceride levels were decreased. The dysregulated liver LPL expression and low plasma triglyceride levels in ZBTB20-deficient mice were normalized by inactivating hepatic LPL expression. ZBTB20 deficiency protected the mice against high-fat diet-induced hyperlipidemia without causing excessive triglyceride accumulation in the liver. Chromatin immunoprecipitation and gel-shift assay studies revealed that ZBTB20 binds to the LPL promoter in the liver. A luciferase reporter assay revealed that ZBTB20 inhibits the transcriptional activity of LPL promoter. The regulation of LPL expression by ZBTB20 is liver-specific under physiological conditions. CONCLUSIONS: Liver ZBTB20 serves as a key regulator of LPL expression and plasma triglyceride metabolism and could be a therapeutic target for hypertriglyceridemia.


Assuntos
Domínio BTB-POZ , Hipertrigliceridemia , Animais , Hepatócitos/metabolismo , Hipertrigliceridemia/etiologia , Hipertrigliceridemia/metabolismo , Lipase Lipoproteica/genética , Lipase Lipoproteica/metabolismo , Fígado/metabolismo , Camundongos , Fatores de Transcrição/metabolismo , Transcrição Gênica , Triglicerídeos/metabolismo , Dedos de Zinco
10.
Breast Cancer Res Treat ; 187(1): 69-80, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33630196

RESUMO

PURPOSE: Current studies on circulating cell-free DNA (cfDNA) have been focusing on its potential as biomarkers in liquid biopsy by detecting its content or genetic and epigenetic changes for the evaluation of tumor burden and therapeutic efficacy. However, the regulatory mechanism of cfDNA release remains unclear. Stat3 has been documented as an oncogene for the development and metastasis of breast cancer cells. In this study, we investigated whether Stat3 affects the release of cfDNA into blood and its association with the number of circulating tumor cells (CTCs). METHODS: The cfDNA level in plasma of patients with breast cancer and healthy volunteers were determined by quantitative real-time PCR. Three mouse breast cancer models with different Stat3 expression were generated and used to established three breast cancer orthotopic animal models to examine the effect of Stat3 on cfDNA release in vivo. Stat3 mediated Epithelial-mesenchymal phenotype transition of CTCs was determined by immunofluorescence assay and Western blot assay. RESULTS: The data showed that Stat3 increased circulating cfDNA, which is correlated with the increased volume of primary tumors and number of CTCs, accompanied with the dynamic EMT changes regulated by Snail induction. Furthermore, the high level of total circulating cfDNA and Stat3-cfDNA in patients with breast cancer were detected by quantitative real-time PCR using GAPDH and Stat3 primers. CONCLUSION: Our results suggested that Stat3 increases the circulating cfDNA and CTCs in breast cancer.


Assuntos
Neoplasias da Mama , Ácidos Nucleicos Livres , Células Neoplásicas Circulantes , Animais , Biomarcadores Tumorais/genética , Neoplasias da Mama/genética , Ácidos Nucleicos Livres/genética , Transição Epitelial-Mesenquimal/genética , Feminino , Humanos , Biópsia Líquida , Camundongos , Fator de Transcrição STAT3/genética
11.
Front Cell Dev Biol ; 9: 583572, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33614637

RESUMO

Anthracyclines resistance is commonly seen in patients with estrogen receptor α (ERα) positive breast cancer. Epithelial-mesenchymal transition (EMT), which is characterized with the loss of epithelial cell polarity, cell adhesion and acquisition of new invasive property, is considered as one of the mechanisms of chemotherapy-induced drug resistance. In order to identify factors that associated with doxorubicin resistance, we performed in vitro and in vivo experiments using human and mouse breast cancer cell lines with different ERα status. Cell survival experiments revealed that ERα-positive cells (MCF-7 and MCF-7/ADR cell lines), were less sensitive to doxorubicin than ERα-negative (MDA-MB-231, MDA-MB-468) cells, and mouse mammary carcinoma cells (4T-1). The expression of E-cadherin reduced in low-invasive ERα-positive MCF-7 cells after treatment with doxorubicin, indicating epithelial mesenchymal transition. In contrast, the expression of E-cadherin was upregulated in high-invasive ERα-negative cells, showing mesenchymal-epithelial transition (MET). Moreover, it was found that the growth inhibition of 4T-1 cells by doxorubicin was positively correlated with the expression of E-cadherin. In a mouse breast cancer xenograft model, E-cadherin was overexpressed in the primary tumor tissues of the doxorubicin-treated mice. In ERα-positive MCF-7 cells, doxorubicin treatment upregulated the expression of EMT-related transcription factors Snail and Twist, that regulate the expression of E-cadherin. Following overexpression of ERα in ERα-negative cells (MDA-MB-231 and MDA-MB-468), doxorubicin enhanced the upregulation of Snail and Twist, decreased expression of E-cadherin, and decreased the sensitivity of cells to doxorubicin. In contrast, inhibition of ERα activity increased the sensitivity to doxorubicin in ERα-positive MCF-7 cells. These data suggest that the regulation of Snail and/or Twist varies depends on different ERα status. Therefore, doxorubicin combined with anti-estrogen receptor α therapy could improve the treatment efficacy of doxorubicin in ERα-positive breast cancer.

12.
J Recept Signal Transduct Res ; 40(1): 49-57, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31948366

RESUMO

Background: Osteosarcoma is a highly malignant primary tumor. Baicalein has broad-spectrum anti-tumor effects. This study aimed to study the specific molecular regulatory mechanism of baicalein in anti-osteosarcoma and the possible regulatory signaling network involved.Methods: In vitro experiment, MG-63 cells treated with 0, 50, 75, and 100 µM of baicalein. Cell viability, proliferation, migration, invasion, cycle, apoptosis, and morphology were detected using 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazoliumbromide (MTT), clone formation, wound healing, Transwell, flow cytometry, Hoechst staining, wound healing and microscopic observation. In addition, cycle, apoptosis and EMT-related proteins and p-ERK/ERK expression level were analyzed using western blotting. In vivo experiments were performed by BALB/c-nude mice model establishment to detect mice and tumor weight, tumor volume, positive rate and p-ERK/ERK expression when mice treated with 100 µM of baicalein.Results: Firstly, the IC50 of baicalein was 67.57 µM. Then, baicalein decreased cell viability, proliferation, migration, invasion, and the expression of CDK2, Cyclin D1, Cyclin E1, Bcl-2, N-cad, Vimentin, MMP-2, MMP-9, p-ERK/ERK, while increased G1 phase numbers, apoptosis and the expression level of p21, p27, cleaved caspase 3/9, Bax, E-cad, ZO-1 in a dose-dependent manner in MG-63 cells. Also, baicalein reduced the body weight, tumor weight and volume and relative expression level of p-ERK/ERK in vivo.Conclusion: Baicalein inhibits cell development, metastasis, and EMT progress and induces cell cycle arrest and apoptosis by regulating ERK signaling pathway in osteosarcoma, and has a visible anti-osteosarcoma effect in vivo.


Assuntos
Apoptose/efeitos dos fármacos , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Flavanonas/farmacologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Osteossarcoma/enzimologia , Osteossarcoma/patologia , Animais , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Feminino , Flavanonas/química , Humanos , Camundongos Endogâmicos BALB C , Camundongos Nus , Invasividade Neoplásica
13.
Int J Oncol ; 53(1): 339-348, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29750424

RESUMO

Doxorubicin (Dox) is widely used in the treatment of triple-negative breast cancer cells (TNBCs), however resistance limits its effectiveness. Cancer stem cells (CSCs) are associated with Dox resistance in MCF-7 estrogen receptor positive breast cancer cells. Signal transducer and activator of transcription 3 (Stat3) may functionally shift non-CSCs towards CSCs. However, whether Stat3 drives the formation of CSCs during the development of resistance in TNBC, and whether a Stat3 inhibitor reverses CSC-mediated Dox resistance, remains to be elucidated. In the present study, human MDA-MB-468 and murine 4T1 mammary carcinoma cell lines with the typical characteristics of TNBCs, were compared with estrogen receptor-positive MCF-7 cells as a model system. The MTT assay was used to detect cytotoxicity of Dox. In addition, the expression levels of CSC-specific markers and transcriptional factors were measured by western blotting, immunofluorescence staining and flow cytometry. The mammosphere formation assay was used to detect stem cell activity. Under long-term continuous treatment with Dox at a low concentration, TNBC cultures not only exhibited a drug-resistant phenotype, but also showed CSC properties. These Dox-resistant TNBC cells showed activation of Stat3 and high expression levels of pluripotency transcription factors octamer-binding transcription factor-4 (Oct-4) and c-Myc, which was different from the high expression of superoxide dismutase 2 (Sox2) in Dox-resistant MCF-7 cells. WP1066 inhibited the phosphorylation of Stat3, and decreased the expression of Oct-4 and c-Myc, leading to a reduction in the CD44-positive cell population, and restoring the sensitivity of the cells to Dox. Taken together, a novel signal circuit of Stat3/Oct-4/c-Myc was identified for regulating stemness-mediated Dox resistance in TNBC. The Stat3 inhibitor WP1066 was able to overcome the resistance to Dox through decreasing the enrichment of CSCs, highlighting the therapeutic potential of WP1066 as a novel sensitizer of Dox-resistant TNBC.


Assuntos
Fator 3 de Transcrição de Octâmero/genética , Proteínas Proto-Oncogênicas c-myc/genética , Fator de Transcrição STAT3/genética , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Doxorrubicina/administração & dosagem , Doxorrubicina/efeitos adversos , Resistencia a Medicamentos Antineoplásicos/genética , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Células MCF-7 , Células-Tronco Neoplásicas/efeitos dos fármacos , Células-Tronco Neoplásicas/patologia , Piridinas/administração & dosagem , Transdução de Sinais/efeitos dos fármacos , Neoplasias de Mama Triplo Negativas/genética , Neoplasias de Mama Triplo Negativas/patologia , Tirfostinas/administração & dosagem
14.
J Opt Soc Am A Opt Image Sci Vis ; 34(6): 1011-1020, 2017 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-29036085

RESUMO

As a competitive machine learning algorithm, the stacked sparse autoencoder (SSA) has achieved outstanding popularity in exploiting high-level features for classification of hyperspectral images (HSIs). In general, in the SSA architecture, the nodes between adjacent layers are fully connected and need to be iteratively fine-tuned during the pretraining stage; however, the nodes of previous layers further away may be less likely to have a dense correlation to the given node of subsequent layers. Therefore, to reduce the classification error and increase the learning rate, this paper proposes the general framework of locally connected SSA; that is, the biologically inspired local receptive field (LRF) constrained SSA architecture is employed to simultaneously characterize the local correlations of spectral features and extract high-level feature representations of hyperspectral data. In addition, the appropriate receptive field constraint is concurrently updated by measuring the spatial distances from the neighbor nodes to the corresponding node. Finally, the efficient random forest classifier is cascaded to the last hidden layer of the SSA architecture as a benchmark classifier. Experimental results on two real HSI datasets demonstrate that the proposed hierarchical LRF constrained stacked sparse autoencoder and random forest (SSARF) provides encouraging results with respect to other contrastive methods, for instance, the improvements of overall accuracy in a range of 0.72%-10.87% for the Indian Pines dataset and 0.74%-7.90% for the Kennedy Space Center dataset; moreover, it generates lower running time compared with the result provided by similar SSARF based methodology.

15.
BMC Complement Altern Med ; 17(1): 192, 2017 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-28376864

RESUMO

BACKGROUND: Oridonin, the major terpene found in Rabdosia rubescens (Henmsl.) Hara, is widely used as a dietary supplement and therapeutic drug. Oridonin has been proven to possess good anti-tumour activity, but little is known about its effect on angiogenesis. The aim of this study was to investigate the antiangiogenic effects of oridonin in vivo and in vitro and prove that oridonin anti-tumour activity is based on suppressing angiogenesis. METHODS: In vitro, the antiangiogenesis effect was studied by proliferation, apoptosis, migration, invasion, and tube formation experiments on human umbilical vascular endothelial cells (HUVECs). In vivo, using the Tg (fli1: GFP) zebrafish model, the embryonic vasculogenesis and postnatal regeneration were evaluated. The vascular endothelial growth factor (VEGF) signalling pathway gene expressions were assessed by reverse transcription-polymerase chain reaction (RT-PCR). Furthermore, the inhibition effects on tumour growth and metastasis were observed using a xenograft zebrafish tumour model and xenograft nude mouse tumour model. Angiogenesis was assayed by immunostaining with cluster of differentiation 31. Importantly, the proteins were identified as being differentially expressed in an in vivo model by two-dimensional electrophoresis-mass spectrometry (2D-MS) and western blot (WB). RESULTS: The results indicated that oridonin inhibited HUVEC proliferation, migration, invasion, and tube formation and induced cell apoptosis. Oridonin inhibited zebrafish angiogenesis during embryonic development and tail fin regeneration. RT-PCR showed that oridonin decreased the VEGFA, VEGFR2, and VEGFR3 expressions in zebrafish, while the TP53 expression increased. Moreover, oridonin had strong effects on tumour growth and metastasis in vivo. 2D-MS identified a total of 50 proteins differentially expressed (17 up-expressed, 28 down-expressed). Lastly, WB showed that Claudin 1, Claudin 4, and Claudin 7 were closely related to tumour growth and metastasis. CONCLUSION: This study demonstrated that oridonin could inhibit tumour growth and metastasis, which mainly based on oridonin antiangiogenic effects. Claudin 1, Claudin 4, and Claudin 7 were the main contributors to the mechanism.


Assuntos
Inibidores da Angiogênese/farmacologia , Diterpenos do Tipo Caurano/farmacologia , Isodon/química , Animais , Antineoplásicos Fitogênicos/isolamento & purificação , Antineoplásicos Fitogênicos/farmacologia , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Células Endoteliais da Veia Umbilical Humana , Humanos , Masculino , Camundongos , Camundongos Nus , Peixe-Zebra
16.
Biotechnol Appl Biochem ; 63(1): 138-44, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-25273976

RESUMO

This article presents a novel SPR imaging biomolecular interaction detection method based on time domain phase modulation. An experimental apparatus of SPR imaging biomolecular interaction detection based on TDPM is established to detect biomolecular interaction. During the experimental pretreatment process, we prepared the 2×2 lysozyme array chip and detected lysozyme thermal condensation state with the experimental apparatus. Using the Stoilov algorithm, we were able to extract the changed phase information as well as obtain the interactive SPR curves and calculate kinetic parameters. This method can sensitively acquire real-time phase change caused by biomolecular interaction based on interference imaging and resolve the related bioinformation, which is a potential tool for proteomics research.


Assuntos
Muramidase/química , Ressonância de Plasmônio de Superfície , Algoritmos , Animais , Desenho de Equipamento , Humanos , Conformação Proteica , Desnaturação Proteica , Ressonância de Plasmônio de Superfície/instrumentação , Ressonância de Plasmônio de Superfície/métodos , Temperatura
17.
Physiol Plant ; 136(1): 30-44, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19508366

RESUMO

Hydrogen peroxide (H(2)O(2)) plays a key role in the regulation of plant responses to various environmental stresses and modulates the expression of related genes including those encoding antioxidant enzymes. A wheat oxalate oxidase (OxO) gene was transformed and expressed in tobacco for production of H(2)O(2). The transgenic plants exhibited enhanced OxO activities and H(2)O(2) concentrations, which was blocked by inhibitors of OxO. The transgenic plants showed increased tolerance to methyl viologen (MV) or high light-induced oxidative stress in both short-time and long-time tests by measuring their maximal photochemical efficiency of PSII (F(v)/F(m)), ion leakage and malondialdehyde. Higher activities and transcripts of antioxidant enzymes (superoxide dismutase, catalase, ascorbate peroxidase and glutathione reductase) were observed in the transgenic plants compared to their wild-type controls under normal growth conditions. Pretreatments with inhibitors of OxO and scavenger of H(2)O(2) blocked the increase of tolerance to MV-induced or high light-induced oxidative stress, as well as the induction of antioxidant enzyme activities. Pretreatments with H(2)O(2) increased tolerance to oxidative stresses and antioxidant enzyme activities. It is suggested that H(2)O(2) produced by OxO in the transgenic tobacco plants triggers the signaling pathways to upregulate expressions of antioxidant enzyme genes, which in turn results in the increase of tolerance to MV-induced and high light-induced oxidative stresses.


Assuntos
Peróxido de Hidrogênio/metabolismo , Estresse Oxidativo , Oxirredutases/metabolismo , Antioxidantes/metabolismo , Clorofila/análise , Luz , Malondialdeído/metabolismo , Oxirredutases/genética , Paraquat/farmacologia , Complexo de Proteína do Fotossistema II/metabolismo , Plantas Geneticamente Modificadas/enzimologia , Plantas Geneticamente Modificadas/genética , /genética , Triticum/enzimologia , Triticum/genética
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