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1.
Br J Cancer ; 131(7): 1212-1223, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39174739

RESUMO

BACKGROUND: Liver cancer stem cells (LCSCs) significantly impact chemo-resistance and recurrence in liver cancer. Dopamine receptor D4 (DRD4) is known to enhance the cancer stem cell (CSC) phenotype in glioblastoma and correlates with poor prognosis in some non-central nervous system tumors; however, its influence on LCSCs remains uncertain. METHODS: To investigate the gene and protein expression profiles of DRD4 in LCSCs and non-LCSCs, we utilized transcriptome sequencing and Western blotting analysis. Bioinformatics analysis and immunohistochemistry were employed to assess the correlation between DRD4 expression levels and the pathological characteristics of liver cancer patients. The impact of DRD4 on LCSC phenotypes and signaling pathways were explored using pharmacological or gene-editing techniques. Additionally, the effect of DRD4 on the protein expression and intracellular localization of ß-catenin were examined using Western blotting and immunofluorescence. RESULTS: DRD4 expression is significantly elevated in LCSCs and correlates with short survival in liver cancer. The expression and activity of DRD4 are positive to resistance, self renewal and tumorigenicity in HCC. Mechanistically, DRD4 stabilizes ß-catenin and promotes its entry into the nucleus via activating the PI3K/Akt/GSK-3ß pathway, thereby enhancing LCSC phenotypes. CONCLUSIONS: Inhibiting DRD4 expression and activation offers a promising targeted therapy for eradicating LCSCs and relieve chemo-resistance.


Assuntos
Resistencia a Medicamentos Antineoplásicos , Neoplasias Hepáticas , Células-Tronco Neoplásicas , Proteínas Proto-Oncogênicas c-akt , Receptores de Dopamina D4 , Transdução de Sinais , beta Catenina , Humanos , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/patologia , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/tratamento farmacológico , Resistencia a Medicamentos Antineoplásicos/genética , beta Catenina/metabolismo , beta Catenina/genética , Receptores de Dopamina D4/genética , Receptores de Dopamina D4/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Camundongos , Animais , Linhagem Celular Tumoral , Fenótipo , Masculino , Regulação Neoplásica da Expressão Gênica , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/tratamento farmacológico , Feminino , Camundongos Nus
2.
Cancer Sci ; 114(10): 3914-3923, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37562810

RESUMO

Current studies have shown that ARNTL, an important clock gene, plays an anticancer role and is downregulated in certain types of cancer. However, the biological functions and mechanisms of ARNTL in tumors remain largely unknown. This study aimed to elucidate how ARNTL-induced autophagy impacts the biological properties of tongue squamous cell carcinoma (TSCC) cells and the mechanisms by which ARNTL expression activates autophagy. ARNTL was stably overexpressed in TSCC cells to investigate its functions in vitro and in vivo. We found that activation of autophagy induced by ARNTL decreases cell proliferation, enhances cell death, and hinders the migratory ability of TSCC cells. Moreover, ARNTL antagonizes the AKT/mTOR pathway, which potentiates autophagy induction. The manipulation of Akt activation cancels the effects of ARNTL overexpression on the biological behaviors of TSCC cells. Furthermore, after the addition of SC79, the upregulated BAX expression due to ARNTL overexpression and downregulated expressions of BCL-2 and MMP2 were remarkably rescued. In vivo tumorigenicity assays and immunohistochemistry also confirmed that ARNTL overexpression suppresses tumor development. Our study found for the first time that ARNTL inhibits the malignant behaviors of oral cancer cells by regulating autophagy in an AKT/mTOR pathway-dependent manner, which provides a novel theoretical basis for the potential future application of ARNTL to treat patients with oral cancer.

3.
Br J Cancer ; 129(9): 1397-1408, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37543671

RESUMO

BACKGROUND: Long non-coding RNAs (lncRNAs)-related immune genes (lrRIGs) play a crucial role in the development and progression of lung adenocarcinoma (LUAD). However, reliable prognostic signatures based on lrRIGs have not yet been identified. METHODS: We screened lrRIGs associated with the prognosis of LUAD using The Cancer Genome Atlas (TCGA) database and then established a novel prognostic nine-gene signature composed of CD79A, INHA, SHC3, LIFR, TNFRSF11A, GPI, F2RL1, SEMA7A and WFDC2 through bioinformatic approaches. A risk score derived from this gene signature was used to divide LUAD patients into the low- and high-risk groups. The latter was confirmed to have markedly worse overall survival (O.S.). A nomogram was developed using the risk score and other independent prognostic elements, demonstrating excellent performance in predicting the O.S. rate of LUAD patients. RESULTS: We observed that the infiltration of diverse immune cell subtypes and response to immunotherapy and chemotherapy significantly differed between the low- and high-risk groups. CONCLUSIONS: Overall, stratification based on this gene signature could be used to guide better therapeutic management and improve outcomes for LUAD patients.


Assuntos
Adenocarcinoma , Neoplasias Pulmonares , RNA Longo não Codificante , Humanos , Imunoterapia , Biologia Computacional , Pulmão , Prognóstico
4.
Breast Cancer Res Treat ; 197(2): 255-267, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36369502

RESUMO

PURPOSE: Triple-negative breast cancer (TNBC) represents the worst prognostic subtype of breast cancer and lacks targeted therapeutic drugs. Signal transducer and activator of transcription 3 (STAT3) is overexpressed and constitutively activated in TNBCs and associated with poor patient outcomes. However, no agents targeting STAT3 have been successfully developed and marketed. Selective Estrogen Receptor Modulators (SERMs) have been reported as potential inhibitors of the IL-6/STAT3 signaling pathway. Naphthalene compounds have good pharmacological activity and significant anti-cancer activity. In this study, we synthesized a new series of naphthalene derivatives with the general structure of SERM and evaluated their effects on TNBC and STAT3 signals. METHODS: A new series of compounds based on the scaffold of SERMs and an amino group were designed and screened based on the structure-activity relationship by MTT assay. The binding activity of SMY002 to STAT3 was predicted and validated by docking and SPR. The STAT3 signaling target and anti-cancer effects of SMY002 were evaluated with three TNBC cell lines and the mice transplanted tumor model. RESULTS: Among the compounds, SMY002 displayed the most potent activity, which could directly interact with STAT3 SH2-domain, and strongly inhibit the phosphorylation, dimerization, nuclear distribution, transcriptional activity, and target genes expression of STAT3. Furthermore, SMY002 markedly suppressed migration, invasion, survival, growth, and metastasis of TNBC cells in vitro and in vivo via down-regulating the expression of Cyclin D1 and MMP9. CONCLUSIONS: SMY002 can significantly inhibit the growth and metastasis of TNBC cells by targeting the STAT3 signal.


Assuntos
Neoplasias de Mama Triplo Negativas , Humanos , Animais , Camundongos , Neoplasias de Mama Triplo Negativas/patologia , Fator de Transcrição STAT3/metabolismo , Moduladores Seletivos de Receptor Estrogênico/farmacologia , Transdução de Sinais , Proliferação de Células , Naftalenos/farmacologia , Naftalenos/uso terapêutico , Linhagem Celular Tumoral
5.
J Gastroenterol Hepatol ; 38(1): 138-152, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36300571

RESUMO

BACKGROUND AND AIM: Liver cancer stem cells (LCSCs) cause therapeutic refractoriness and relapse in hepatocellular carcinoma. Heat shock factor 1 (HSF1) plays versatile roles in multiple cancers. However, the role of HSF1 in LCSCs is not well understood. This study investigated the function and signal mechanisms of HSF1 in maintaining LCSC phenotypes. METHODS: We established two LCSC lines, HepG2-R and HuH-7-R. Constitutive activation of HSF1 was observed in these LCSCs. Specific short hairpin RNAs (shRNAs) and chemical inhibitors were used to identify the relationship between HSF1 expression and LCSCs phenotypes. RESULTS: We revealed a concomitant activation modality involving HSF1 and STAT3 in LCSCs and liver cancer tissues. We also found that liver cancer patients whose HSF1 and STAT3 mRNA expression levels were high presented with unfavorable clinicopathological characteristics. Moreover, the secretion of interleukin-8 (IL-8) was elevated in the LCSC medium and was directly regulated by HSF1 at the transcriptional level. In turn, IL-8 activated HSF1 and STAT3 signaling, and a neutralizing IL-8 antibody inhibited HSF1 and STAT3 activity, reduced cancer stem cell marker expression, and decreased LCSC microsphere formation. Simultaneous intervention with HSF1 and STAT3 led to synergistically suppressed stemness acquisition and growth suppression in the LCSCs in vivo and in vitro. CONCLUSIONS: Our study indicates that IL-8 mediates the crosstalk between the HSF1 and Stat3 signaling pathways in LCSCs and that the combined targeting of HSF1 and STAT3 is a promising treatment strategy for patients with advanced liver cancer.


Assuntos
Fatores de Transcrição de Choque Térmico , Neoplasias Hepáticas , Células-Tronco Neoplásicas , Fator de Transcrição STAT3 , Humanos , Comunicação Autócrina , Linhagem Celular Tumoral , Fatores de Transcrição de Choque Térmico/metabolismo , Interleucina-8/metabolismo , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Recidiva Local de Neoplasia/patologia , Células-Tronco Neoplásicas/metabolismo , Fator de Transcrição STAT3/genética , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais
6.
BMC Oral Health ; 23(1): 400, 2023 06 16.
Artigo em Inglês | MEDLINE | ID: mdl-37328866

RESUMO

BACKGROUND: Caries in young children has received more and more attention. The study of the oral microbiota may help to understand the polymicrobial etiology of dental caries. OBJECTIVES: To investigate the diversity and structure of microbial communities in saliva samples from 5-year-old children with versus without dental caries. METHODS: A total of 36 saliva samples were collected from 18 children with high caries (HB group) and from 18 children without caries (NB group). Then, 16S rDNA was amplified from bacterial samples using polymerase chain reaction, and high-throughput sequencing was performed using Illumina Novaseq platforms. RESULTS: Sequences were clustered into operational taxonomic units (OTUs), which were distributed among 16 phyla, 26 classes, 56 orders, 93 families, 173 genera, and 218 species. Firmicutes, Bacteroides, Proteobacteria, Actinobacteria, Fusobacteria, Patescibacteria, Epsilonbacteraeota, Cyanobacteria, Acidobacteria and Spirochaetes were basically the same in different groups, but their relative abundances were different. The core microbiome was defined as the species from 218 shared microbial taxa. The alpha diversity test showed that there were no significant differences in microbial abundance and diversity between the high caries and no caries groups. The results from principal coordinate analysis (PCoA) and hierarchical clustering showed that the two groups had similar microorganisms. The biomarkers of different groups were defined by LEfSe analysis to identify potential caries-related and health-related bacteria. Co-occurrence network analysis of dominant genera showed that oral microbial communities in the no caries group were more complex and aggregated than those in the high caries group. Finally, the PICRUSt algorithm was used to predict the function of the microbial communities from saliva samples. The obtained results showed that mineral absorption was greater in the no caries group than in the high caries group. BugBase was used to determine phenotypes present in microbial community samples. The obtained results showed that Streptococcus was greater in the high caries group than in the no caries group. CONCLUSION: Findings of this study provide a comprehensive understanding of the microbiological etiology of dental caries in 5-year-old children and are expected to provide new methods for its prevention and treatment.


Assuntos
Cárie Dentária , Microbiota , Humanos , Cárie Dentária/microbiologia , Saliva/microbiologia , Bactérias/genética , Microbiota/genética , Streptococcus , RNA Ribossômico 16S/genética
7.
Sensors (Basel) ; 22(16)2022 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-36016027

RESUMO

Direction of arrival (DOA) estimation is an essential and fundamental part of array signal processing, which has been widely used in radio monitoring, autonomous driving of vehicles, intelligent navigation, etc. However, it remains a challenge to accurately estimate DOA for multiple-input multiple-output (MIMO) radar in impulsive noise environments. To address this problem, an off-grid DOA estimation method for monostatic MIMO radar is proposed to deal with non-circular signals under impulsive noise. In the proposed method, firstly, based on the property of non-circular signal and array structure, a virtual array output was built and a real-valued sparse representation for the signal model was constructed. Then, an off-grid sparse Bayesian learning (SBL) framework is proposed and further applied to the virtual array to construct novel off-grid sparse model. Finally, off-grid DOA estimation was realized through the solution of the sparse reconstruction with high accuracy even in impulsive noise. Numerous simulations were performed to compare the algorithm with existing methods. Simulation results verify that the proposed off-grid DOA method enables evident performance improvement in terms of accuracy and robustness compared with other works on impulsive noise.

8.
Sensors (Basel) ; 22(3)2022 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-35161668

RESUMO

Bars are significant load-carrying components in engineering structures. In particular, L-bars are typical structural components commonly used in truss structures and have typical irregular asymmetric cross-sections. To ensure the safety of load-carrying bars, much research has been done for non-destructive testing (NDT). Ultrasonic guided waves have been widely applied in various NDT techniques for bars as a result of the long-range propagation, low attenuation, and high sensitivity to damages. Though good for inspection of ultrasonic guided waves in symmetric cross-section bar-like structures, the application in asymmetric ones lacks further research. Moreover, traditional damage detection in bars using ultrasonic guided waves usually depends on a single-mode at a lower frequency with lower sensitivity and accuracy. To make full use of all frequencies and modes, a multi-mode characteristic-based damage detection method is presented with the sum of multiple signals (SoM) strategy for L-bars with asymmetric cross-section. To control the desired mode in multi-mode ultrasonic guided waves, excitation optimization and weighted gathering are carried out by the analysis of the semi-analytical finite element (SAFE) method and the normal mode expansion (NME) method. An L-bar example with the asymmetric cross-section of 35 mm × 20 mm × 3 mm is used to specialize the proposed method, and some finite element (FE) models have been simulated to validate the mode control. In addition, one PZT is applied as a contrast in order to validate the multielement mode control. Then, more FE simulations experiments for damage detection have been performed to validate the damage detection method and verify the improvement in detection accuracy and damage sensitivity.

9.
J Basic Microbiol ; 62(6): 740-749, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35199357

RESUMO

Phosphoglucose isomerase (PGI) is a key enzyme that participates in polysaccharide synthesis, which is responsible for the interconversion of glucose-6-phosphate (G-6-P) and fructose-6-phosphate (F-6-P), but there is little research focusing on its role in fungi, especially in higher basidiomycetes. The pgi gene was cloned from Lentinula edodes and named lepgi. Then, the lepgi-silenced strains were constructed by RNA interference. In this study, we found that lepgi-silenced strains had significantly less biomass than the wild-type (WT) strain. Furthermore, the extracellular polysaccharide (EPS) and intracellular polysaccharide (IPS) levels increased 1.5- to 3-fold and 1.5-fold, respectively, in lepgi-silenced strains. Moreover, the cell wall integrity in the silenced strains was also altered, which might be due to changes in the compounds and structure of the cell wall. The results showed that compared to WT, silencing lepgi led to a significant decrease of approximately 40% in the ß-1,3-glucan content, and there was a significant increase of 2-3-fold in the chitin content. These findings provide support for studying the biological functions of lepgi in L. edodes.


Assuntos
Cogumelos Shiitake , Parede Celular , Clonagem Molecular , Glucose-6-Fosfato Isomerase/genética , Polissacarídeos , Cogumelos Shiitake/genética
10.
Environ Microbiol ; 23(2): 682-695, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-32483888

RESUMO

Nitric oxide (NO) is an important signalling molecule in stress response of organisms. We previously reported that NO decreases heat stress (HS)-induced ganoderic acid (GA) accumulation in Ganoderma lucidum. To explore the mechanisms by which NO modulates GA biosynthesis under HS, the effect of NO on the reactive oxygen species (ROS) content was examined. The results showed that NO decreased the production of mitochondrial ROS (mitROS) by 60% under HS. Further research revealed that NO reduced the mitROS content by inhibiting aconitase (Acon) activity. The GA content in Acon-silenced (Aconi) strains treated with NO donor did not differ significantly from that in untreated Aconi strains. To study the mechanism by which Acon activity is inhibited, the S-nitrosylation level of Acon was determined. Biotin-switch technology and mass spectrometry analysis were used to show that Acon is S-nitrosylated at the Cys-594 amino acid residue. Substitution of Cys-594 with a Ser, which cannot be S-nitrosylated, abolished the responsiveness of Acon to the NO-induced reduction in its enzymatic activity. These findings demonstrate that NO inhibits Acon activity through S-nitrosylation at Cys-594. In summary, these findings describe mechanism by which NO regulates GA biosynthesis via S-nitrosylation of Acon under HS condition in G. lucidum.


Assuntos
Aconitato Hidratase/antagonistas & inibidores , Óxido Nítrico/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Reishi/metabolismo , Triterpenos/metabolismo , Aconitato Hidratase/metabolismo , Resposta ao Choque Térmico/fisiologia , Mitocôndrias/metabolismo , Estresse Oxidativo/fisiologia , Transdução de Sinais
11.
Biochem Biophys Res Commun ; 529(2): 133-139, 2020 08 20.
Artigo em Inglês | MEDLINE | ID: mdl-32703401

RESUMO

The unique metabolic characteristics and diverse functions of marrow adipose tissue (MAT) have drawn more attention recently. Previously, we have reported that CBFA2T2 is required for BMP2-induced osteogenic differentiation of mesenchymal stem/stromal cells (MSCs). In the present study, we further investigated the role of CBFA2T2 in regulation of adipogenic differentiation in mouse bone marrow-derived MSCs (mBMSCs) and human dental pulp stem cells (hDPSCs). We found CBFA2T2 expression was dramatically upregulated during adipogenesis of mBMSCs and hDPSCs. More importantly, knockdown of CBFA2T2 in mBMSCs and hDPSCs significantly inhibited the process of adipogenic differentiation, as revealed by the expression of adipogenic markers and Oil Red O staining. Mechanistically, we found knockdown of CBFA2T2 led to an increase in H3K9me2 and H3K9me3 levels at promoter of CEBPA, an essential transcription factor of adipogenesis. Taken together, these findings suggest CBFA2T2 is key regulator of adipogenic differentiation of MSCs, and it may represent a therapeutic target for conditions with excessive MAT.


Assuntos
Adipogenia , Proteínas Estimuladoras de Ligação a CCAAT/metabolismo , Polpa Dentária/citologia , Células-Tronco Mesenquimais/citologia , Proteínas Repressoras/metabolismo , Adulto , Animais , Proteínas Estimuladoras de Ligação a CCAAT/genética , Células Cultivadas , Polpa Dentária/metabolismo , Técnicas de Silenciamento de Genes , Humanos , Células-Tronco Mesenquimais/metabolismo , Camundongos , Proteínas Repressoras/genética , Adulto Jovem
12.
Med Sci Monit ; 26: e920776, 2020 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-32307404

RESUMO

BACKGROUND This study aimed to evaluate the desensitizing effect of toothpaste containing the active ingredients of an extract of Galla chinensis, both in vitro and in patients with dentin hypersensitivity. MATERIAL AND METHODS Ninety-eight patients with dentin hypersensitivity were divided into two study groups and given toothpaste containing either the active ingredients of Galla chinensis extract and sodium fluoride, or a control toothpaste containing only sodium fluoride. Assessments included the tactile stimulation test and the Schiff cold air sensitivity scale, which were conducted at the baseline examination and after 4 and 8 weeks of dental brushing. Twenty-five intact human premolars from 24 patients with dentin hypersensitivity were prepared and randomly divided into four groups, the untreated baseline group, the study group, the positive control group, and the control group. After brushing with different toothpaste for 7 days, the effects on dentinal tubule sealing in each group was determined by scanning electron microscopy (SEM), and the degree of dentinal tubule plugging and diameter of the open dentinal tubules were calculated. RESULTS Toothpaste containing the active ingredients of Galla chinensis and sodium fluoride significantly reduced the degree of dentin hypersensitivity when compared with toothpaste containing sodium fluoride alone after 4 weeks and 8 weeks of use. Toothpaste containing the active ingredients of Galla chinensis significantly reduced the number and diameter of the open dentinal tubules. CONCLUSIONS Toothpaste that contained the active ingredients of Galla chinensis and sodium fluoride reduced the symptoms of dentin hypersensitivity by sealing the dentinal tubules.


Assuntos
Sensibilidade da Dentina/tratamento farmacológico , Rhus/metabolismo , Cremes Dentais/farmacologia , Adulto , Idoso , Dentina/efeitos dos fármacos , Método Duplo-Cego , Feminino , Fluoretos , Humanos , Masculino , Medicina Tradicional Chinesa/métodos , Microscopia Eletrônica de Varredura , Pessoa de Meia-Idade , Fosfatos , Fluoreto de Sódio/farmacologia , Escovação Dentária , Cremes Dentais/uso terapêutico , Resultado do Tratamento
13.
Cell Mol Biol (Noisy-le-grand) ; 63(11): 1-4, 2017 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-29208185

RESUMO

Although many researchers have studied on the association between vitamin D receptor (VDR) BsmI polymorphism and periodontitis, this association remains elusive. To further assess the effects of VDR BsmI polymorphism on the risk of periodontitis, a meta-analysis was performed in a single ethnic group. We searched PubMed and Chinese databases for relevant studies till April 2017. The strength of the associations were assessed used pooled odds ratios (ORs) and 95% confidence intervals (CIs). Six studies including 757 periodontitis cases and 670 controls were identified at last. In the total analyses, VDR BsmI polymorphism was not associated with the risk of periodontitis in all models. The subgroup analyses suggested a significantly reduced risk of periodontitis in South China. In conclusion, our meta-analysis showed that VDR BsmI polymorphism was associated with the decreased risk of periodontitis in Chinese individuals from South China, and further studies in other ethic groups are required for definite conclusions.


Assuntos
Periodontite/genética , Polimorfismo Genético/genética , Receptores de Calcitriol/genética , Predisposição Genética para Doença/genética , Humanos
14.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 42(9): 1030-1036, 2017 Sep 28.
Artigo em Zh | MEDLINE | ID: mdl-28989147

RESUMO

OBJECTIVE: To explore the effect of low intensity pulsed ultrasound (LIPUS) on TGF-ß1/Smad 2, 3 signal pathway during the dentin injury and repair.
 Methods: Among 25 Sprague-Dawley rats, 5 rats served as a blank control group without treatment. The remaining 20 rats received modified caries preparation inbilateral maxillary first molars to establish a model of dentin-pulp injury and repair. The right maxillary first molars served as a LIPUS group, which received LIPUS irradiation (frequency: 1.5 MHz, pulse width: 200 µs, pulse repetition frequency: 1 kHz, spatial averaged temporal averaged intensity: 30 mW/cm2, 20 min/d), and the left maxillary first molars served as a cavity-prepared group, which received fake LIPUS irradiation. The rats were sacrificed at 1, 3, 5, 7 and 14 days after LIPUS irradiation. Immunohistochemical staining and Image-pro plus 6.0 were applied to detect the expression and distribution of transforming growth factor-beta1 (TGF-ß1) and small mothers against decapentaplegic 2/3(Smad 2 and Smad 3).
 Results: Immunohistochemical staining showed that the expression of TGF-ß1 and Smad 2, 3 were low innormal pulp, but they were increased in different degree after dentin injury. The result of image analysis showed that the expression of TGF-ß1 in the cavity-prepared group gradually increased at the first day and peaked at day 5, and then it returned to normal level at day 14. However, the expression of TGF-ß1 in the LIPUS group were significantly higher than that in the cavity-prepared group at day 3 and 5 (both P<0.05). The expressions of Smad 2,3 in both the LIPUS group and the cavity-prepared group were consistently increased all the way, but the expressions in the LIPUS group were higher compared with that in the cavity-prepared group (P<0.05).
 Conclusion: The TGF-ß1/Smad 2, 3 signal pathway can be activated during the dentin injury and repair. LIPUS can up-regulate the expression of TGF-ß1 and Smad 2, 3 in the early period, which may take part in the dentin-pulp complex injury and repair process.


Assuntos
Dentina , Regulação da Expressão Gênica , Fator de Crescimento Transformador beta1/genética , Ondas Ultrassônicas , Animais , Dentina/lesões , Ratos , Ratos Sprague-Dawley , Transdução de Sinais , Cicatrização/genética
15.
BMC Cancer ; 15: 832, 2015 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-26526356

RESUMO

BACKGROUND: Our previous studies show that ß2-adrenergic receptor (ß2-AR) is highly expressed in most Her2-overexpressing breast cancers. However, the mechanisms underlying upregulation of the ß2-AR expression in Her2-overexpressing breast cancer cells are not fully understood. The clinical significance of the ß2-AR overexpression in breast cancer is unclear. METHODS: Human breast cancer cells MCF-7 and MCF-7/Her2 were transfected with the let-7 mimics or inhibitors. The expression of ß2-AR was analyzed by Western blot. The ß2-AR status in primary and metastatic sites of breast cancer and the human breast cancer tissue microarrays containing 49 primary tumors and 50 metastatic lymph node tissues was analyzed by immunohistochemistry. The correlation of lymph node metastasis with the ß2-AR level was determined in 59 primary tumor tissues from the patients with Her2-positive breast cancer. The clinical prognostic significance of the ß2-AR overexpression in the patients with Her2-positive breast cancers was evaluated by a retrospective study. RESULTS: The let-7f level in Her2-overexpressing breast cancer cells SKBR3 and BT474 was significantly lower than that in MCF-7 cells, which express low level of Her2. Ectopic expression of Her2 in MCF-7 cells (MCF-7/Her2) represses the expression of microRNA let-7f, which is previously identified to regulate baseline ß2-AR expression. The treatment with MEK1/2 inhibitors PD98059 or PD184352 effectively restored the let-7f level, suggesting that Her2-overexpression-mediated ERK constitutive activation inhibited let-7f, leading to the upregulation of the ß2-AR expression. The transfection with the let-7f mimics markedly downregulated the ß2-AR level, whereas the let-7 inhibitor significantly upregulated the ß2-AR expression in both parental MCF-7 and MCF-7/Her2 cells. In addition, treatment of MCF-7/Her2 cells with isoproterenol resulted in a concentration-dependent reduction of the let-7f expression, demonstrating that the inhibitory effect of Her2 overexpression on let-7f can be reinforced by agonist-triggered ß2-AR activation. We further demonstrate that high level of ß2-AR associates with lymph node metastasis and poor outcome in the patients with Her2-positive breast cancer. CONCLUSIONS: The mutual and reciprocal interaction between Her2, ß2-AR, and let-7f may maintain a high level of ß2-AR in breast cancer cells. Our data suggest that ß2-AR may be a new useful biomarker for predicting prognosis in Her2-positive breast cancer and may also be a promising selective therapeutic target for the aggressive subtype of breast cancer.


Assuntos
Neoplasias da Mama/genética , MicroRNAs/biossíntese , Receptor ErbB-2/biossíntese , Receptores Adrenérgicos beta 2/biossíntese , Neoplasias da Mama/patologia , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Células MCF-7 , MicroRNAs/genética , Prognóstico , Receptor ErbB-2/genética , Receptores Adrenérgicos beta 2/genética , Transdução de Sinais
16.
J Immunol ; 190(11): 5600-8, 2013 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-23630346

RESUMO

Trastuzumab is currently used for patients with Her2(+) advanced gastric cancer. However, the response rate to trastuzumab among the patients is low. The molecular mechanisms underlying trastuzumab resistance in gastric cancer are unknown. Our in vitro data show that activation of ß2-adrenergic receptor (ß2-AR) triggered by catecholamine caused "targeting failure" of trastuzumab in gastric cancer cells. The antitumor activities of trastuzumab were significantly impeded by chronic catecholamine stimulation in gastric cancer cells and in the mice bearing human gastric cancer xenografts. Mechanistically, catecholamine induced upregulation of the MUC4 expression at both transcription and protein levels via activating STAT3 and ERK. The effects of catecholamine could be effectively blocked by ß2-AR antagonist ICI-118,551, indicating that ß2-AR-mediated signaling pathway plays a key role in upregulation of MUC4, which was previously demonstrated to interfere with the recognition and physical binding of trastuzumab to Her2 molecules. Moreover, a significant elevation of the MUC4 level was observed in the xenograft tissues in nude mice chronically treated with isoproterenol. Knockdown of MUC4 restored the binding activities of trastuzumab to Her2-overexpressing gastric cancer cells. In addition, coexpression of ß2-AR and MUC4 were observed in gastric cancer tissues. Our data indicated a novel trastuzumab resistance mechanism, by which catecholamine-induced ß2-AR activation mediates desensitization of gastric cancer cells to trastuzumab through upregulating the MUC4 expression.


Assuntos
Anticorpos Monoclonais Humanizados/farmacologia , Catecolaminas/farmacologia , Resistencia a Medicamentos Antineoplásicos/genética , Mucina-4/genética , Receptores Adrenérgicos beta 2/metabolismo , Neoplasias Gástricas/genética , Neoplasias Gástricas/metabolismo , Animais , Anticorpos Monoclonais Humanizados/metabolismo , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Modelos Animais de Doenças , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Feminino , Expressão Gênica , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Isoproterenol/farmacologia , Camundongos , Ligação Proteica , Receptor ErbB-2/genética , Receptor ErbB-2/metabolismo , Receptores Adrenérgicos beta 2/genética , Fator de Transcrição STAT3/metabolismo , Transcrição Gênica/efeitos dos fármacos , Trastuzumab , Ensaios Antitumorais Modelo de Xenoenxerto
17.
Cancer Metastasis Rev ; 32(3-4): 603-21, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23674223

RESUMO

Central and sympathetic nervous systems govern functional activities of many organs. Solid tumors like organs are also innervated by sympathetic nerve fibers. Neurotransmitters released from sympathetic nerve fibers can modulate biological behaviors of tumor cells. Multiple physiologic processes of tumor development may be dominated by central and sympathetic nervous systems as well. Recent studies suggest that dysfunction of central and sympathetic nervous systems and disorder of the hormone network induced by psychological stress may influence malignant progression of cancer by inhibiting the functions of immune system, regulating metabolic reprogramming of tumor cells, and inducing interactions between tumor and stromal cells. Over-release of inflammatory cytokines by tumors may aggravate emotional disorder, triggering the vicious cycles in tumor microenvironment and host macroenvironment. It is reasonable to hypothesize that cancer progression may be controlled by central and sympathetic nervous systems. In this review, we will focus on the recent information about the impacts of central and sympathetic nervous systems on tumor invasion and metastasis.


Assuntos
Sistema Nervoso Central , Neoplasias/etiologia , Neoplasias/patologia , Sistema Nervoso Periférico , Animais , Microambiente Celular , Sistema Nervoso Central/metabolismo , Sistema Nervoso Central/fisiopatologia , Hormônios/metabolismo , Humanos , Sistema Hipotálamo-Hipofisário/metabolismo , Metástase Neoplásica , Sistema Nervoso Periférico/metabolismo , Sistema Nervoso Periférico/fisiopatologia , Sistema Hipófise-Suprarrenal/metabolismo , Receptores Nicotínicos/metabolismo , Transdução de Sinais , Estresse Psicológico , Microambiente Tumoral
18.
Ultrasonics ; 138: 107253, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38309036

RESUMO

In ultrasonic reflection method, the precision of defect detection in thick carbon fiber reinforced plastics (CFRP) is compromised by acoustic energy attenuation. An energy-compensation reverse time migration (ECRTM) method is proposed to identify multiple defects accurately. Forward and backward wavefields are formed using the finite element method within an anisotropic acoustic model based on the Christoffel equation and Bond transformation. To enhance the imaging quality of CFRP laminates, a novel cross-correlation imaging condition is introduced to compensate for energy dissipation caused by geometric diffusion and variations of the far-field radiation intensity at the emitter with the propagation direction. Employing ultrasonic detection technology with a multi-element array, numerical and experimental research on defect imaging was conducted, considering delamination with various sizes and positions in a multidirectional CFRP laminate. In comparison to other ultrasonic imaging methods, the near-surface artifacts in RTM images are mitigated by the far-field radiation directivity factor, while the deep information is enhanced by the geometric diffusion compensation factor in the ECRTM images. As a result, the precise position of delamination in CFRP laminates is achievable, demonstrating superior imaging capabilities, especially for deep delamination.

19.
Ann Med Surg (Lond) ; 86(10): 5793-5801, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39359823

RESUMO

Radiotherapy is widely regarded as the primary therapeutic modality for nasopharyngeal cancer (NPC). Studies have shown that cancer cells with high resistance to radiation, known as radioresistant cancer cells, may cause residual illness, which in turn might contribute to the occurrence of cancer recurrence and metastasis. It has been shown that cancer stem-like cells (CSCs) exhibit resistance to radiation therapy. In the present study, fractionated doses of radiation-induced epithelial-mesenchymal transition (EMT) and ALDH+ CSCs phenotype of NPC tumor spheroids. Furthermore, it has been shown that cells with elevated ALDH activity have increased resistance to the effects of fractionated irradiation. Nuclear factor erythroid-2-related factor 2 (Nrf2) plays a pivotal role in regulating cellular antioxidant systems. A large body of evidence suggests that Nrf2 plays a significant role in the development of radioresistance in cancer. The authors' research revealed that the application of fractionated irradiation resulted in a decline in Nrf2-dependent reactive oxygen species (ROS) levels, thereby mitigating DNA damage in ALDH+ stem-like NPC cells. In addition, immunofluorescence analysis revealed that subsequent to the process of fractionated irradiation of ALDH+ cells, activated Nrf2 was predominantly localized inside the nucleus. Immunofluorescent analysis also revealed that the presence of the nuclear Nrf2+/NQO1+/ALDH1+ axis might potentially serve as an indicator of poor prognosis and resistance to radiotherapy in patients with NPC. Thus, the authors' findings strongly suggest that the radioresistance of ALDH-positive NPC CSCs to fractionated irradiation is regulated by nuclear Nrf2 accumulation. Nrf2 exerts its effects through the downstream effector NQO1/ALDH1, which depends on ROS attenuation.

20.
J Pathol ; 228(2): 148-57, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22287315

RESUMO

Glucocorticoids are stress-responsive neuroendocrine mediators and play an important role in malignant progression, especially in solid tumours. We demonstrate a novel mechanism by which glucocorticoids modulate p53-dependent miR-145 expression in HPV-positive cervical cancer cells through induction of E6 proteins. We found that expression of miR-145 was reduced in cervical cancer tissues. Cortisol induced HPV-E6 expression and suppressed p53 and miR-145 in cervical cancer cells. MiR-145 expression in cervical cancer cells was wild-type p53-dependent, and cortisol-induced down-regulation of miR-145 expression prevented chemotherapy-induced apoptosis, whereas over-expression of miR-145 enhanced sensitivity to mitomycin and reversed the chemoresistance induced by glucocorticoids. We also show that miR-145 augments the effects of p53 by suppressing the inhibitors of p53 in cervical cancer cells, suggesting that miR-145 plays a role in p53 tumour suppression. Finally, we demonstrate that miR-145 inhibits both the motility and invasion of cervical cancer cells. Our findings identify a novel pathway through which the neuroendocrine macroenvironment affects cervical tumour growth, invasion and therapy resistance and show that miR-145 may serve as a target for cervical cancer therapy. Copyright © 2012 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.


Assuntos
Adenocarcinoma/genética , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Hidrocortisona/farmacologia , MicroRNAs/genética , Proteínas Oncogênicas Virais/genética , Infecções por Papillomavirus/genética , Proteína Supressora de Tumor p53/genética , Neoplasias do Colo do Útero/genética , Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/virologia , Anti-Inflamatórios/farmacologia , Apoptose , Northern Blotting , Ensaios de Migração Celular , Proteínas de Ligação a DNA , Regulação para Baixo/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/genética , Feminino , Citometria de Fluxo , Células HeLa , Humanos , Infecções por Papillomavirus/tratamento farmacológico , Infecções por Papillomavirus/virologia , Reação em Cadeia da Polimerase em Tempo Real , Transfecção , Neoplasias do Colo do Útero/tratamento farmacológico , Neoplasias do Colo do Útero/virologia
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