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1.
Environ Res ; 252(Pt 1): 118745, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38527716

RESUMO

Exposure to cadmium may increase risk of urolithiasis, but the results remain inconclusive. This systematic review and meta-analysis aimed to access the association between cadmium exposure and urolithiasis. We searched Medline/PubMed, Embase, Web of Science Core Collection, and Cochrane Central for studies. The primary outcome was the incidence of urolithiasis compared to reference groups. We used relative risk as the summary effect measure. This meta-analysis included eight observational studies and divided into 39 study populations. Among 63,051 subjects, 5018 (7.96%) individuals had urolithiasis. The results indicated that people with an increment of 0.1 µg/g creatinine in urinary cadmium had a 2% increased risk of urolithiasis (pooled relative risk [RR], 1.02; 95% confidence interval [CI], 1.01-1.03) and there is no difference in the risk of urolithiasis in high and low cadmium exposure levels. Meanwhile, people with an increment of 0.1 µg/L in urinary cadmium had a 4% increased risk of urolithiasis (pooled RR, 1.04; 95% CI, 1.02-1.07). Our findings also showed similar associations in both sex, different region (Sweden, China, and Thailand), general and occupational population. The results indicate that cadmium exposure was significantly associated with an elevated risk of urolithiasis. Therefore, it is imperative to take steps to minimize cadmium exposure.


Assuntos
Cádmio , Urolitíase , Urolitíase/induzido quimicamente , Urolitíase/urina , Urolitíase/epidemiologia , Cádmio/urina , Humanos , Exposição Ambiental/análise , Exposição Ambiental/efeitos adversos , Poluentes Ambientais/urina
2.
Nat Commun ; 15(1): 1021, 2024 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-38310114

RESUMO

The epidermal growth factor receptor (EGFR) plays important roles in multiple cellular events, including growth, differentiation, and motility. A major mechanism of downregulating EGFR function involves its endocytic transport to the lysosome. Sorting of proteins into intracellular pathways involves cargo adaptors recognizing sorting signals on cargo proteins. A dileucine-based sorting signal has been identified previously for the sorting of endosomal EGFR to the lysosome, but a cargo adaptor that recognizes this signal remains unknown. Here, we find that phosphoglycerate kinase 1 (PGK1) is recruited to endosomal membrane upon its phosphorylation, where it binds to the dileucine sorting signal in EGFR to promote the lysosomal transport of this receptor. We also elucidate two mechanisms that act in concert to promote PGK1 recruitment to endosomal membrane, a lipid-based mechanism that involves phosphatidylinositol 4,5-bisphosphate [PI(4,5)P2] and a protein-based mechanism that involves hepatocyte growth factor receptor substrate (Hrs). These findings reveal an unexpected function for a metabolic enzyme and advance the mechanistic understanding of how EGFR is transported to the lysosome.


Assuntos
Receptores ErbB , Fosfoglicerato Quinase , Fosfoglicerato Quinase/metabolismo , Receptores ErbB/metabolismo , Endossomos/metabolismo , Proteínas/metabolismo , Lisossomos/metabolismo , Transporte Proteico/fisiologia , Complexos Endossomais de Distribuição Requeridos para Transporte/metabolismo
3.
ACS Pharmacol Transl Sci ; 7(1): 161-175, 2024 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-38230272

RESUMO

ATP-binding cassette (ABC) transporters, notably ABCB1 (P-glycoprotein) and ABCG2, play a crucial role in the development of multidrug resistance (MDR) during the administration of chemotherapy for cancer patients. With a lack of approved treatments for addressing multidrug-resistant cancers, MDR remains a substantial challenge to the effective management of cancer. Rather than focusing on developing novel synthetic inhibitors, a promising approach to combat MDR involves repurposing approved therapeutic agents to enhance the sensitivity to cytotoxic antiproliferative drugs of multidrug-resistant cancer cells with high expression of ABCB1 or ABCG2. In this investigation, we observed a substantial reversal of MDR conferred by ABCB1 and ABCG2 in multidrug-resistant cancer cells through the use of mobocertinib, an approved third-generation inhibitor of the epidermal growth factor receptor (EGFR) tyrosine kinase. Mobocertinib demonstrated the ability to hinder drug transport function without causing changes in protein expression. The interactions between mobocertinib and ABCB1, as well as ABCG2, were validated through ATPase assays. Furthermore, in silico docking simulations were utilized to substantiate the binding of mobocertinib within the drug-binding pockets of both ABCB1 and ABCG2. We conclude that further testing of mobocertinib in combination therapy is warranted for patients with tumors expressing elevated levels of the ABC drug transporters ABCB1 and ABCG2.

4.
Pharmaceuticals (Basel) ; 16(11)2023 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-38004460

RESUMO

The high expression of the ATP-binding cassette (ABC) drug transporter ABCG2 in cancer cells contributes to the emergence of multidrug resistance (MDR) in individuals afflicted with either solid tumors or blood cancers. MDR poses a major impediment in the realm of clinical cancer chemotherapy. Recently, substantial endeavors have been dedicated to identifying bioactive compounds isolated from nature capable of counteracting ABCG2-mediated MDR in cancer cells. Imperatorin, a natural coumarin derivative renowned for its diverse pharmacological properties, has not previously been explored for its impact on cancer drug resistance. This study investigates the chemosensitizing potential of imperatorin in ABCG2-overexpressing cancer cells. Experimental results reveal that at sub-toxic concentrations, imperatorin significantly antagonizes the activity of ABCG2 and reverses ABCG2-mediated MDR in a concentration-dependent manner. Furthermore, biochemical data and in silico analysis of imperatorin docking to the inward-open conformation of human ABCG2 indicate that imperatorin directly interacts with multiple residues situated within the transmembrane substrate-binding pocket of ABCG2. Taken together, these results furnish substantiation that imperatorin holds promise for further evaluation as a potent inhibitor of ABCG2, warranting exploration in combination drug therapy to enhance the effectiveness of therapeutic agents for patients afflicted with tumors that exhibit high levels of ABCG2.

5.
Int J Mol Sci ; 24(18)2023 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-37762275

RESUMO

ATP-binding cassette transporters, including ABCB1 (P-glycoprotein) and ABCG2 (BCRP/MXR/ABCP), are pivotal in multidrug resistance (MDR) development in cancer patients undergoing conventional chemotherapy. The absence of approved therapeutic agents for multidrug-resistant cancers presents a significant challenge in effectively treating cancer. Researchers propose repurposing existing drugs to sensitize multidrug-resistant cancer cells, which overexpress ABCB1 or ABCG2, to conventional anticancer drugs. The goal of this study is to assess whether furmonertinib, a third-generation epidermal growth factor receptor tyrosine kinase inhibitor overcomes drug resistance mediated by ABCB1 and ABCG2 transporters. Furmonertinib stands out due to its ability to inhibit drug transport without affecting protein expression. The discovery of this characteristic was validated through ATPase assays, which revealed interactions between furmonertinib and ABCB1/ABCG2. Additionally, in silico docking of furmonertinib offered insights into potential interaction sites within the drug-binding pockets of ABCB1 and ABCG2, providing a better understanding of the underlying mechanisms responsible for the reversal of MDR by this repurposed drug. Given the encouraging results, we propose that furmonertinib should be explored as a potential candidate for combination therapy in patients with tumors that have high levels of ABCB1 and/or ABCG2. This combination therapy holds the potential to enhance the effectiveness of conventional anticancer drugs and presents a promising strategy for overcoming MDR in cancer treatment.

6.
Ann Plast Surg ; 89(4): 373-375, 2022 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-36149977

RESUMO

ABSTRACT: Metabolic disturbance in patients of amyotrophic lateral sclerosis is a rare presentation that might be related to disease progression and outcomes. Hypermetabolic status after major burn injury remains a critical issue in the modern medical care. Here, we present a rare case of a patient sporadic amyotrophic lateral sclerosis who suffered from minor burn injury (8% total body surface area), developing critical hyperosmolar hyperglycemic state during early hospitalization. Newly diagnosed diabetes is established and found related to the underlying disease of this patient. The accumulative metabolic alteration among vulnerable patients of amyotrophic lateral sclerosis and burn injury is noteworthy. Judicious monitoring of fluid and metabolic status helps to prevent the occurrence of acute hyperosmolar hyperglycemic state.


Assuntos
Esclerose Lateral Amiotrófica , Queimaduras , Coma Hiperglicêmico Hiperosmolar não Cetótico , Esclerose Lateral Amiotrófica/complicações , Queimaduras/complicações , Progressão da Doença , Humanos , Coma Hiperglicêmico Hiperosmolar não Cetótico/complicações , Coma Hiperglicêmico Hiperosmolar não Cetótico/diagnóstico
7.
Environ Int ; 169: 107533, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36150296

RESUMO

It is always difficult to compare, let alone estimate, the difference of air pollutant concentrations before and after closure of a major source because the pollutants cannot be traced or predicted after entering the ambient. Indeed, we are not aware of any studies specifically related to the air pollutants impacted by a winding-down source. In this work, we applied nine years (2010-2018) online measurement of air pollutants (including PM10, PM2.5, NO2, SO2, O3 and VOCs) to investigate (i) the temporal behavior of air pollutants before and after closure of an oil refinery park by using pair-wise statistics and correlations between wind speed and direction, and (ii) the source impacts on O3 concentrations using PMF coupled with multiple linear regression (MLR) analysis (PMF-MLR). Example applications are presented at two monitoring sites (A and B) close to the Kaohsiung Oil Refinery (KOR), located in the southern industrial city of Taiwan. The results show that the KOR shutdown changed air pollutant concentrations to a certain extent in these study areas. We also conclude that, instead of using propylene-equivalent and ozone formation potential (OFP) concentrations, it is better to estimate the formation of O3 based on PMF-MLR analysis as developed in this study. The PMF analysis has identified various VOCs sources at both sites including solvent usage, petrochemical industrial sources, industrial emissions, vehicle-related sources, vegetation emissions and aged air-masses. Also, the MLR model shows that both the background sources and petrochemical industrial sources may significantly change O3 concentrations.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Ozônio , Compostos Orgânicos Voláteis , Poluentes Atmosféricos/análise , Poluição do Ar/análise , China , Monitoramento Ambiental/métodos , Dióxido de Nitrogênio/análise , Indústria de Petróleo e Gás , Ozônio/análise , Material Particulado/análise , Solventes/análise , Emissões de Veículos/análise , Compostos Orgânicos Voláteis/análise
8.
Int J Mol Sci ; 23(6)2022 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-35328658

RESUMO

Deficiency in DNA damage response (DDR) genes leads to impaired DNA repair functions that will induce genomic instability and facilitate cancer development. However, alterations of DDR genes can serve as biomarkers for the selection of suitable patients to receive specific therapeutics, such as immune checkpoint blockade (ICB) therapy. In addition, certain altered DDR genes can be ideal therapeutic targets through adapting the mechanism of synthetic lethality. Recent studies indicate that targeting DDR can improve cancer immunotherapy by modulating the immune response mediated by cGAS-STING-interferon signaling. Investigations of the interplay of DDR-targeting and ICB therapies provide more effective treatment options for cancer patients. This review introduces the mechanisms of DDR and discusses their crucial roles in cancer therapy based on the concepts of synthetic lethality and ICB. The contemporary clinical trials of DDR-targeting and ICB therapies in breast, colorectal, and pancreatic cancers are included.


Assuntos
Dano ao DNA , Neoplasias , Reparo do DNA , Humanos , Imunidade , Imunoterapia , Neoplasias/tratamento farmacológico , Neoplasias/genética
9.
Front Immunol ; 13: 807454, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35145520

RESUMO

Background: Innate immunity, armed with pattern recognition receptors including Toll-like receptors (TLR), is critical for immune cell activation and the connection to anti-microbial adaptive immunity. However, information regarding the impact of age on the innate immunity in response to SARS-CoV2 adenovirus vector vaccines and its association with specific immune responses remains scarce. Methods: Fifteen subjects between 25-35 years (the young group) and five subjects between 60-70 years (the older adult group) were enrolled before ChAdOx1 nCoV-19 (AZD1222) vaccination. We determined activation markers and cytokine production of monocyte, natural killer (NK) cells and B cells ex vivo stimulated with TLR agonist (poly (I:C) for TLR3; LPS for TLR4; imiquimod for TLR7; CpG for TLR9) before vaccination and 3-5 days after each jab with flow cytometry. Anti-SARS-CoV2 neutralization antibody titers (surrogate virus neutralization tests, sVNTs) were measured using serum collected 2 months after the first jab and one month after full vaccination. Results: The older adult vaccinees had weaker vaccine-induced sVNTs than young vaccinees after 1st jab (47.2±19.3% vs. 21.2±22.2%, p value<0.05), but this difference became insignificant after the 2nd jab. Imiquimod, LPS and CpG strongly induced CD86 expression in IgD+CD27- naïve and IgD-CD27+ memory B cells in the young group. In contrast, only the IgD+ CD27- naïve B cells responded to these TLR agonists in the older adult group. Imiquimode strongly induced the CD86 expression in CD14+ monocytes in the young group but not in the older adult group. After vaccination, the young group had significantly higher IFN-γ expression in CD3- CD56dim NK cells after the 1st jab, whilst the older adult group had significantly higher IFN-γ and granzyme B expression in CD56bright NK cells after the 2nd jab (all p value <0.05). The IFN-γ expression in CD56dim and CD56bright NK cells after the first vaccination and CD86 expression in CD14+ monocyte and IgD-CD27-double-negative B cells after LPS and imiquimod stimulation correlated with vaccine-induced antibody responses. Conclusions: The innate immune responses after the first vaccination correlated with the neutralizing antibody production. Older people may have defective innate immune responses by TLR stimulation and weak or delayed innate immune activation profile after vaccination compared with young people.


Assuntos
Anticorpos Neutralizantes/sangue , Anticorpos Antivirais/sangue , Linfócitos B/imunologia , ChAdOx1 nCoV-19/imunologia , Células Matadoras Naturais/imunologia , SARS-CoV-2/imunologia , Adulto , Idoso , COVID-19/prevenção & controle , Feminino , Humanos , Imiquimode/farmacologia , Imunidade Inata/imunologia , Imunossenescência/imunologia , Interferon gama/sangue , Masculino , Pessoa de Meia-Idade , Poli I-C/administração & dosagem , Poli I-C/imunologia , Receptores Toll-Like/imunologia , Vacinação
11.
J Nat Prod ; 84(9): 2544-2553, 2021 09 24.
Artigo em Inglês | MEDLINE | ID: mdl-34496204

RESUMO

Elevated expression of the ATP-binding cassette (ABC) drug transporter ABCG2 in cancer cells contributes to the development of the multidrug resistance phenotype in patients with advanced non-small-cell lung cancer (NSCLC). Due to the lack of U.S. Food and Drug Administration (FDA)-approved synthetic inhibitors of ABCG2, significant efforts have been invested in discovering bioactive compounds of plant origin that are capable of reversing ABCG2-mediated multidrug resistance in cancer cells. Sophoraflavanone G (SFG), a phytoncide isolated from the plant species Sophora flavescens, is known to possess a wide spectrum of pharmacological activities, including antibacterial, anti-inflammatory, antimalarial, and antiproliferative effects. In the present study, the chemosensitizing effect of SFG in ABCG2-overexpressing NSCLC cells was investigated. Experimental results demonstrate that at subtoxic concentrations SFG significantly reversed ABCG2-mediated multidrug resistance in a concentration-dependent manner. Additional biochemical data and in silico docking analysis of SFG to the inward-open conformation of human ABCG2 indicate that SFG inhibited the drug transport function of ABCG2 by interacting with residues within the transmembrane substrate-binding pocket of ABCG2. Collectively, these findings provide evidence that SFG has the potential to be further tested as an effective inhibitor of ABCG2 to improve the efficacy of therapeutic drugs in patients with advanced NSCLC.


Assuntos
Antineoplásicos/farmacologia , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Resistência a Múltiplos Medicamentos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Flavanonas/farmacologia , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP , Linhagem Celular Tumoral , Humanos , Simulação de Acoplamento Molecular , Proteínas de Neoplasias
12.
Biochem Pharmacol ; 188: 114516, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33713643

RESUMO

The overexpression of the human ATP-binding cassette (ABC) drug transporter ABCB1 (P-glycoprotein, P-gp) or ABCG2 (breast cancer resistance protein, BCRP) in cancer cells often contributes significantly to the development of multidrug resistance (MDR) in cancer patients. Previous reports have demonstrated that some epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) could modulate the activity of ABCB1 and/or ABCG2 in human cancer cells, whereas some EGFR TKIs are transport substrates of these transporters. Almonertinib (HS-10296) is a promising, orally available third-generation EGFR TKI for the treatment of EGFR T790M mutation-positive non-small cell lung cancer (NSCLC) in patients who have progressed on or after other EGFR TKI therapies. Additional clinical trials are currently in progress to study almonertinib as monotherapy and in combination with other agents in patients with NSCLC. In the present work, we found that neither ABCB1 nor ABCG2 confers significant resistance to almonertinib. More importantly, we discovered that almonertinib was able to reverse MDR mediated by ABCB1, but not ABCG2, in multidrug-resistant cancer cells at submicromolar concentrations by inhibiting the drug transport activity of ABCB1 without affecting its expression level. These findings are further supported by in silico docking of almonertinib in the drug-binding pocket of ABCB1. In summary, our study revealed an additional activity of almonertinib to re-sensitize ABCB1-overexpressing multidrug-resistant cancer cells to conventional chemotherapeutic drugs, which may be beneficial for cancer patients and warrant further investigation.


Assuntos
Acrilamidas/farmacologia , Antineoplásicos/farmacologia , Resistência a Múltiplos Medicamentos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Indóis/farmacologia , Pirimidinas/farmacologia , Subfamília B de Transportador de Cassetes de Ligação de ATP/antagonistas & inibidores , Subfamília B de Transportador de Cassetes de Ligação de ATP/biossíntese , Subfamília B de Transportador de Cassetes de Ligação de ATP/genética , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Relação Dose-Resposta a Droga , Resistencia a Medicamentos Antineoplásicos/fisiologia , Receptores ErbB/antagonistas & inibidores , Receptores ErbB/biossíntese , Regulação Neoplásica da Expressão Gênica , Células HEK293 , Humanos , Estrutura Secundária de Proteína
13.
Urology ; 144: 38-45, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32711011

RESUMO

OBJECTIVE: To examine the utility of the Clinical Frailty Scale (CFS) in predicting outcomes in older adults with urologic malignancies undergoing curative surgeries. METHODS: This prospective observational cohort study was conducted in a university-based tertiary medical center. Patients aged 75 years or older who were scheduled to undergo curative surgery for a urologic malignancy from January 2017 to December 2017 were recruited. Patients were grouped according to the CFS scores. The primary postoperative outcome measures were a major complication within 30 days and a decline in the activities of daily living (ADL) within 30 days and 90 days. Multivariable analyses and the area under the receiver operating characteristic curve were performed to investigate the association between the CFS and postoperative outcomes. RESULTS: A total of 82 patients, 50% women, were enrolled with mean age 81.6 years. The CFS was significantly associated with postoperative outcomes in a dose-response relationship. When compared with those with a CFS <5, patients with CFS scores ≥5 had a 10.3-times higher risk for a major complication, 8.5-times and 21.4-times higher risk for a decline in ADL within 30 days and 90 days. The area under the receiver operating characteristic curves for the CFS to predict a major complication, the 30-day decline in ADL and the 90-day decline in ADL were 0.60, 0.73, and 0.79. CONCLUSION: A higher CFS score predicted a higher risk of poor outcomes in this population. It is recommended that patients with higher CFS scores, especially above 5, are needed to receive further multidisciplinary perioperative care.


Assuntos
Atividades Cotidianas , Fragilidade/classificação , Complicações Pós-Operatórias/etiologia , Neoplasias Urológicas/cirurgia , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Análise Multivariada , Estudos Prospectivos , Neoplasias da Próstata/cirurgia , Curva ROC , Risco , Fatores de Tempo , Resultado do Tratamento
14.
Cancers (Basel) ; 12(6)2020 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-32466597

RESUMO

The development of multidrug resistance (MDR) in cancer patients, which is often associated with the overexpression of ABCB1 (MDR1, P-glycoprotein) in cancer cells, remains a significant problem in cancer chemotherapy. ABCB1 is one of the major adenosine triphosphate (ATP)-binding cassette (ABC) transporters that can actively efflux a range of anticancer drugs out of cancer cells, causing MDR. Given the lack of Food and Drug Administration (FDA)-approved treatment for multidrug-resistant cancers, we explored the prospect of repurposing erdafitinib, the first fibroblast growth factor receptor (FGFR) kinase inhibitor approved by the FDA, to reverse MDR mediated by ABCB1. We discovered that by reducing the function of ABCB1, erdafitinib significantly resensitized ABCB1-overexpressing multidrug-resistant cancer cells to therapeutic drugs at sub-toxic concentrations. Results of erdafitinib-stimulated ABCB1 ATPase activity and in silico docking analysis of erdafitinib binding to the substrate-binding pocket of ABCB1 further support the interaction between erdafitinib and ABCB1. Moreover, our data suggest that ABCB1 is not a major mechanism of resistance to erdafitinib in cancer cells. In conclusion, we revealed an additional action of erdafitinib as a potential treatment option for multidrug-resistant cancers, which should be evaluated in future drug combination trials.

15.
Cancers (Basel) ; 12(1)2020 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-31941029

RESUMO

The development of multidrug resistance (MDR) in cancer patients driven by the overexpression of ATP-binding cassette (ABC) transporter ABCB1 or ABCG2 in cancer cells presents one of the most daunting therapeutic complications for clinical scientists to resolve. Despite many novel therapeutic strategies that have been tested over the years, there is still no approved treatment for multidrug-resistant cancers to date. We have recently adopted a drug repurposing approach to identify therapeutic agents that are clinically active and at the same time, capable of reversing multidrug resistance mediated by ABCB1 and ABCG2. In the present study, we investigated the effect of sitravatinib, a novel multitargeted receptor tyrosine kinase inhibitor, on human ABCB1 and ABCG2 in multidrug-resistant cancer cell lines. We discovered that at submicromolar concentrations, sitravatinib re-sensitizes ABCB1- and ABCG2-overexpressing multidrug-resistant cancer cells to chemotherapeutic drugs. We found that sitravatinib blocks the drug efflux function of ABCB1 and ABCG2 in a concentration-dependent manner but does not significantly alter the protein expression of ABCB1 or ABCG2 in multidrug-resistant cancer cells. In conclusion, we reveal a potential drug repositioning treatment option for multidrug-resistant cancers by targeting ABCB1 and ABCG2 with sitravatinib and should be further investigated in future clinical trials.

16.
Biomed Res Int ; 2019: 3843295, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31467888

RESUMO

Breast cancer is a main cause of disease and death for women globally. Because of the limitations of traditional mammography and ultrasonography, magnetic resonance imaging (MRI) has gradually become an important radiological method for breast cancer assessment over the past decades. MRI is free of the problems related to radiation exposure and provides excellent image resolution and contrast. However, a disadvantage is the injection of contrast agent, which is toxic for some patients (such as patients with chronic renal disease or pregnant and lactating women). Recent findings of gadolinium deposits in the brain are also a concern. To address these issues, this paper develops an intravoxel incoherent motion- (IVIM-) MRI-based histogram analysis approach, which takes advantage of several hyperspectral techniques, such as the band expansion process (BEP), to expand a multispectral image to hyperspectral images and create an automatic target generation process (ATGP). After automatically finding suspected targets, further detection was attained by using kernel constrained energy minimization (KCEM). A decision tree and histogram analysis were applied to classify breast tissue via quantitative analysis for detected lesions, which were used to distinguish between three categories of breast tissue: malignant tumors (i.e., central and peripheral zone), cysts, and normal breast tissues. The experimental results demonstrated that the proposed IVIM-MRI-based histogram analysis approach can effectively differentiate between these three breast tissue types.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Imagem de Difusão por Ressonância Magnética/métodos , Aumento da Imagem/métodos , Interpretação de Imagem Assistida por Computador/métodos , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/patologia , Meios de Contraste/uso terapêutico , Feminino , Humanos , Imageamento Tridimensional/métodos , Mamografia/métodos
17.
Cancer Res ; 79(21): 5550-5562, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31431462

RESUMO

Neuroblastoma is the most common malignant disease of infancy, and amplification of the MYCN oncogene is closely associated with poor prognosis. Recently, expression of MYCN was shown to be inversely correlated with aryl hydrocarbon receptor (AHR) expression in neuroblastoma, and overexpression of AHR downregulated MYCN expression, promoting cell differentiation. Therefore, we further investigated the potential of AHR to serve as a prognostic indicator or a therapeutic target in neuroblastoma. First, the clinical significance of AHR in neuroblastoma was examined. Positive AHR immunostaining strongly correlated with differentiated histology of neuroblastoma and predicted better survival for patients. The mouse xenograft model showed that overexpression of AHR significantly suppressed neuroblastoma tumor growth. In addition, activation of AHR by the endogenous ligand kynurenine inhibited cell proliferation and promoted cell differentiation in vitro and in vivo. kynurenine treatment also upregulated the expression of KISS1, a tumor metastasis suppressor, and attenuated metastasis in the xenograft model. Finally, analysis of KISS1 levels in neuroblastoma patient tumors using the R2: Genomics Analysis and Visualization Platform revealed that KISS1 expression positively correlated with AHR, and high KISS1 expression predicted better survival for patients. In conclusion, our results indicate that AHR is a novel prognostic biomarker for neuroblastoma, and that overexpression or activation of AHR offers a new therapeutic possibility for patients with neuroblastoma. SIGNIFICANCE: These findings show that AHR may function as a tumor suppressor in childhood neuroblastoma, potentially influencing the aetiologic and therapeutic targeting of the disease.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Cinurenina/genética , Neuroblastoma/genética , Neuroblastoma/patologia , Receptores de Hidrocarboneto Arílico/genética , Animais , Diferenciação Celular/genética , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Criança , Pré-Escolar , Progressão da Doença , Feminino , Amplificação de Genes/genética , Regulação Neoplásica da Expressão Gênica/genética , Genes Supressores de Tumor/fisiologia , Humanos , Lactente , Recém-Nascido , Kisspeptinas/genética , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Proteína Proto-Oncogênica N-Myc/genética
18.
BMC Nephrol ; 20(1): 266, 2019 07 17.
Artigo em Inglês | MEDLINE | ID: mdl-31315601

RESUMO

BACKGROUND: Sclerostin, an antagonist of the Wingless-type mouse mammary tumor virus integration site (Wnt) pathway that regulates bone metabolism, is a potential contributor of chronic kidney disease (CKD)-mineral and bone disorder (MBD), which has various forms of presentation, from osteoporosis to vascular calcification. The positive association of sclerostin with bone mineral density (BMD) has been demonstrated in CKD and hemodialysis (HD) patients but not in peritoneal dialysis (PD) patients. This study assessed the association between sclerostin and BMD in PD patients. METHODS: Eighty-nine PD patients were enrolled; their sera were collected for measurement of sclerostin and other CKD-MBD-related markers. BMD was also assessed simultaneously. We examined the relationship between sclerostin and each parameter through Spearman correlation analysis and by comparing group data between patients with above- and below-median sclerostin levels. Univariate and multiple logistic regression models were employed to define the most predictive of sclerostin levels in the above-median category. RESULTS: Bivariate analysis revealed that sclerostin was correlated with spine BMD (r = 0.271, P = 0.011), spine BMD T-score (r = 0.274, P = 0.010), spine BMD Z-score (r = 0.237, P = 0.027), and intact parathyroid hormone (PTH; r = - 0.357, P < 0.001) after adjustments for age and sex. High BMD, old age, male sex, increased weight and height, diabetes, and high osteocalcin and uric acid levels were observed in patients with high serum sclerostin levels and an inverse relation was noticed between PTH and sclerostin. Univariate logistic regression analysis demonstrated that BMD is positively correlated with above-median sclerostin levels (odds ratio [OR] = 65.61, P = 0.002); the correlation was retained even after multivariate adjustment (OR = 121.5, P = 0.007). CONCLUSIONS: For the first time, this study demonstrated a positive association between serum sclerostin levels and BMD in the PD population.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/sangue , Densidade Óssea , Diálise Peritoneal , Insuficiência Renal Crônica/sangue , Insuficiência Renal Crônica/terapia , Adulto , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Insuficiência Renal Crônica/metabolismo
19.
J Food Drug Anal ; 26(3): 1024-1032, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29976395

RESUMO

Epidemiological studies have revealed that obesity and being overweight are associated with increased cancer risk. Adipose tissue is regarded as an endocrine organ that secretes proinflammatory cytokines such as tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6), which are related to the progression of hepatocellular carcinoma (HCC). In this study, adipocytes from 3T3-L1 cells were induced and stained with Oil Red O, which revealed marked intracellular lipid accumulation. Adding 15% conditioned medium (CM) from adipogenic -differentiated 3T3-L1 cells, which contained adipocyte-derived factors, to a culture medium of HepG2 cells was discovered to promote cell proliferation by a factor of up to 1.3 compared with the control. Mulberry leaf extract (MLE), with major components including chlorogenic acid and neochlorogenic acid, was revealed to inhibit CM-promoted HepG2 cell proliferation. The inhibitory effect of MLE on the proliferation of the signal network was evaluated. Expression of the CM-activated IκB/NFκB, STAT3, and Akt/mTOR pathways were reduced when MLE was administered. Although adipocyte-derived factors are complex, administrating anti-TNF-α and anti-IL-6 revealed that MLE blocks signal activation promoted by TNF-α and IL-6. Taken together, these results demonstrated that MLE targets the proliferation signal pathway of the inflammatory response of adipocytes in HCC and could be to prevent obesity-mediated liver cancer.


Assuntos
Adipócitos/efeitos dos fármacos , Carcinoma Hepatocelular/fisiopatologia , Proliferação de Células/efeitos dos fármacos , Interleucina-6/metabolismo , Neoplasias Hepáticas/fisiopatologia , Morus/química , Extratos Vegetais/farmacologia , Fator de Necrose Tumoral alfa/metabolismo , Células 3T3-L1 , Adipócitos/citologia , Adipócitos/metabolismo , Animais , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Diferenciação Celular/efeitos dos fármacos , Regulação para Baixo/efeitos dos fármacos , Células Hep G2 , Humanos , Interleucina-6/genética , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Camundongos , NF-kappa B/genética , NF-kappa B/metabolismo , Fator de Necrose Tumoral alfa/genética
20.
J Vis Exp ; (131)2018 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-29443039

RESUMO

We have developed a pair of cell-based reporter gene assays to quantitatively measure γ-secretase cleavage of distinct substrates. This manuscript describes procedures that may be used to monitor γ-secretase-mediated cleavage of either APP-C99 or Notch, using a Gal4 promoter-driven firefly luciferase reporter system. These assays were established by stably co-transfecting HEK293 cells with the Gal4-driven luciferase reporter gene and either the Gal4/VP16-tagged C-terminal fragment of APP (APP-C99; CG cells), or the Gal4/VP16-tagged Notch-ΔE (NΔE; NG cells). Using these reporter assays in parallel, we have demonstrated that an ErbB2 inhibitor, CL-387,785, can preferentially suppress γ-secretase cleavage of APP-C99 in CG cells, but not NΔE in NG cells. The differential responses exhibited by the CG and NG cells, when treated with CL-387,785, represent a preferred characteristic for γ-secretase modulators, and these responses are in stark contrast to the pan-inhibition of γ-secretase induced by DAPT. Our studies provide direct evidence that γ-secretase activities toward different substrates can be differentiated in a cellular context. These new assays may therefore be useful tools in drug discovery for improved AD therapies.


Assuntos
Secretases da Proteína Precursora do Amiloide/análise , Luciferases de Vaga-Lume/química , Receptores Notch/metabolismo , Secretases da Proteína Precursora do Amiloide/metabolismo , Diferenciação Celular/fisiologia , Células HEK293 , Humanos , Luciferases de Vaga-Lume/metabolismo , Especificidade por Substrato , Transfecção
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