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1.
J Cell Sci ; 137(8)2024 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-38661040

RESUMO

Expression levels of the lactate-H+ cotransporter MCT4 (also known as SLC16A3) and its chaperone CD147 (also known as basigin) are upregulated in breast cancers, correlating with decreased patient survival. Here, we test the hypothesis that MCT4 and CD147 favor breast cancer invasion through interdependent effects on extracellular matrix (ECM) degradation. MCT4 and CD147 expression and membrane localization were found to be strongly reciprocally interdependent in MDA-MB-231 breast cancer cells. Overexpression of MCT4 and/or CD147 increased, and their knockdown decreased, migration, invasion and the degradation of fluorescently labeled gelatin. Overexpression of both proteins led to increases in gelatin degradation and appearance of the matrix metalloproteinase (MMP)-generated collagen-I cleavage product reC1M, and these increases were greater than those observed upon overexpression of each protein alone, suggesting a concerted role in ECM degradation. MCT4 and CD147 colocalized with invadopodia markers at the plasma membrane. They also colocalized with MMP14 and the lysosomal marker LAMP1, as well as partially with the autophagosome marker LC3, in F-actin-decorated intracellular vesicles. We conclude that MCT4 and CD147 reciprocally regulate each other and interdependently support migration and invasiveness of MDA-MB-231 breast cancer cells. Mechanistically, this involves MCT4-CD147-dependent stimulation of ECM degradation and specifically of MMP-mediated collagen-I degradation. We suggest that the MCT4-CD147 complex is co-delivered to invadopodia with MMP14.


Assuntos
Basigina , Neoplasias da Mama , Matriz Extracelular , Proteína 1 de Membrana Associada ao Lisossomo , Metaloproteinase 14 da Matriz , Transportadores de Ácidos Monocarboxílicos , Invasividade Neoplásica , Podossomos , Feminino , Humanos , Basigina/metabolismo , Basigina/genética , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Neoplasias da Mama/genética , Linhagem Celular Tumoral , Membrana Celular/metabolismo , Movimento Celular , Matriz Extracelular/metabolismo , Gelatina/metabolismo , Proteínas de Membrana Lisossomal/metabolismo , Proteínas de Membrana Lisossomal/genética , Metaloproteinase 14 da Matriz/metabolismo , Metaloproteinase 14 da Matriz/genética , Proteínas Associadas aos Microtúbulos/metabolismo , Proteínas Associadas aos Microtúbulos/genética , Transportadores de Ácidos Monocarboxílicos/metabolismo , Transportadores de Ácidos Monocarboxílicos/genética , Proteínas Musculares/metabolismo , Proteínas Musculares/genética , Invasividade Neoplásica/genética , Podossomos/metabolismo
2.
EMBO J ; 40(7): e106065, 2021 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-33615517

RESUMO

5-Fluorouracil (5-FU) is a widely used chemotherapeutic drug, but the mechanisms underlying 5-FU efficacy in immunocompetent hosts in vivo remain largely elusive. Through modeling 5-FU response of murine colon and melanoma tumors, we report that effective reduction of tumor burden by 5-FU is dependent on anti-tumor immunity triggered by the activation of cancer-cell-intrinsic STING. While the loss of STING does not induce 5-FU resistance in vitro, effective 5-FU responsiveness in vivo requires cancer-cell-intrinsic cGAS, STING, and subsequent type I interferon (IFN) production, as well as IFN-sensing by bone-marrow-derived cells. In the absence of cancer-cell-intrinsic STING, a much higher dose of 5-FU is needed to reduce tumor burden. 5-FU treatment leads to increased intratumoral T cells, and T-cell depletion significantly reduces the efficacy of 5-FU in vivo. In human colorectal specimens, higher STING expression is associated with better survival and responsiveness to chemotherapy. Our results support a model in which 5-FU triggers cancer-cell-initiated anti-tumor immunity to reduce tumor burden, and our findings could be harnessed to improve therapeutic effectiveness and toxicity for colon and other cancers.


Assuntos
Antineoplásicos/farmacologia , Resistencia a Medicamentos Antineoplásicos , Fluoruracila/farmacologia , Proteínas de Membrana/metabolismo , Microambiente Tumoral/imunologia , Animais , Linhagem Celular Tumoral , Células Cultivadas , Feminino , Humanos , Interferon Tipo I/metabolismo , Proteínas de Membrana/genética , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Nucleotidiltransferases/metabolismo , Linfócitos T/imunologia , Microambiente Tumoral/efeitos dos fármacos
3.
Kidney Int ; 106(4): 679-687, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38964736

RESUMO

The fluorescent compound relmapirazin has been rationally designed for use in point-of-care measurement of glomerular filtration rate (GFR), with attributes including negligible protein binding, negligible metabolites in vivo, negligible tubular secretion, and excellent chemical and photo stability. Twenty-four nonclinical assays were performed in accordance with FDA requirements yielding negligible toxicology concerns. Here, a clinical study was performed to validate relmapirazin as a GFR tracer in patients by comparison to iohexol. This was evaluated in 120 adults at three clinical sites with eGFR values ranging from normal to Stage 4 chronic kidney disease. Relmapirazin and iohexol were administered intravenously in consecutive boluses to each subject and serial blood samples obtained over the subsequent 12 hours. Plasma concentrations were measured and the corresponding plasma GFR for each agent was determined using a standard two-compartment pharmacokinetic assessment. Urine from each subject was collected for the entire 12-hour study period to measure the amount of administered dose appearing in the urine. A near perfect linear regression correlation was observed between the GFRs measured by these two tracers (r2=0.99). Bland-Altman analysis confirmed agreement between these two measures of GFR (limits of agreement -7.0 to +5.6 mL/min; mean of -0.7 mL/min). The GFR determined by relmapirazin was independent of GFR stratification by chronic kidney disease stage, and importantly by race. The percent of the administered relmapirazin dose recovered in the urine was greater than or equal to that of iohexol with no reported severe adverse events. Thus, relmapirazin may be used as a GFR tracer agent in humans.


Assuntos
Corantes Fluorescentes , Taxa de Filtração Glomerular , Iohexol , Insuficiência Renal Crônica , Humanos , Iohexol/farmacocinética , Iohexol/administração & dosagem , Iohexol/análise , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Insuficiência Renal Crônica/diagnóstico , Insuficiência Renal Crônica/fisiopatologia , Insuficiência Renal Crônica/sangue , Insuficiência Renal Crônica/urina , Corantes Fluorescentes/administração & dosagem , Adulto , Meios de Contraste/farmacocinética , Meios de Contraste/administração & dosagem , Meios de Contraste/efeitos adversos , Rim/fisiopatologia , Reprodutibilidade dos Testes , Adulto Jovem
4.
J Cell Sci ; 135(20)2022 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-36148554

RESUMO

SHARPIN is involved in several cellular processes and promotes cancer progression. However, how the choice between different functions of SHARPIN is post-translationally regulated is unclear. Here, we characterized SHARPIN phosphorylation by mass spectrometry and in vitro kinase assay. Focusing on S131 and S146, we demonstrate that they have a role in SHARPIN-ARP2/3 complex interaction, but play no role in integrin inhibition or LUBAC activation. Consistent with its novel role in ARP2/3 regulation, S146 phosphorylation of SHARPIN promoted lamellipodia formation. We also demonstrate that SHARPIN S146 phosphorylation-mediated ARP2/3 interaction is sensitive to inhibition of ERK1/2 or reactivation of protein phosphatase 2A (PP2A). Notably, CRISPR/Cas9-mediated knockout of SHARPIN abrogated three-dimensional (3D) invasion of several cancer cell lines. The 3D invasion of cancer cells was rescued by overexpression of the wild-type SHARPIN, but not by SHARPIN S146A mutant. Finally, we demonstrate that inhibition of phosphorylation at S146 significantly reduces in vivo metastasis in a zebrafish model. Collectively, these results map SHARPIN phosphorylation sites and identify S146 as a novel phosphorylation switch defining ARP2/3 interaction and cancer cell invasion. This article has an associated First Person interview with the first author of the paper.


Assuntos
Proteína Fosfatase 2 , Peixe-Zebra , Animais , Integrinas , Invasividade Neoplásica , Proteínas do Tecido Nervoso , Fosforilação
5.
Oncologist ; 29(7): 619-628, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38655867

RESUMO

BACKGROUND: CD8+ tumor-infiltrating lymphocyte (TIL) predicts response to anti-PD-(L)1 therapy. However, there remains no standardized method to assess CD8+ TIL in melanoma, and developing a specific, cost-effective, reproducible, and clinically actionable biomarker to anti-PD-(L)1 remains elusive. We report on the development of automatic CD8+ TIL density quantification via whole slide image (WSI) analysis in advanced melanoma patients treated with front-line anti-PD-1 blockade, and correlation immunotherapy response. METHODS: Seventy-eight patients treated with PD-1 inhibitors in the front-line setting between January 2015 and May 2023 at the University of Pittsburgh Cancer Institute were included. CD8+ TIL density was quantified using an image analysis algorithm on digitized WSI. Targeted next-generation sequencing (NGS) was performed to determine tumor mutation burden (TMB) in a subset of 62 patients. ROC curves were used to determine biomarker cutoffs and response to therapy. Correlation between CD8+ TIL density and TMB cutoffs and response to therapy was studied. RESULTS: Higher CD8+ TIL density was significantly associated with improved response to front-line anti-PD-1 across all time points measured. CD8+ TIL density ≥222.9 cells/mm2 reliably segregated responders and non-responders to front-line anti-PD-1 therapy regardless of when response was measured. In a multivariate analysis, patients with CD8+ TIL density exceeding cutoff had significantly improved PFS with a trend toward improved OS. Similarly, increasing TMB was associated with improved response to anti-PD-1, and a cutoff of 14.70 Mut/Mb was associated with improved odds of response. The correlation between TMB and CD8+ TIL density was low, suggesting that each represented independent predictive biomarkers of response. CONCLUSIONS: An automatic digital analysis algorithm provides a standardized method to quantify CD8+ TIL density, which predicts response to front-line anti-PD-1 therapy. CD8+ TIL density and TMB are independent predictors of response to anti-PD-1 blockade.


Assuntos
Biomarcadores Tumorais , Linfócitos T CD8-Positivos , Imunoterapia , Linfócitos do Interstício Tumoral , Melanoma , Mutação , Humanos , Melanoma/tratamento farmacológico , Melanoma/genética , Melanoma/patologia , Melanoma/imunologia , Linfócitos do Interstício Tumoral/imunologia , Linfócitos T CD8-Positivos/imunologia , Feminino , Masculino , Pessoa de Meia-Idade , Biomarcadores Tumorais/genética , Idoso , Imunoterapia/métodos , Adulto , Inibidores de Checkpoint Imunológico/uso terapêutico , Inibidores de Checkpoint Imunológico/farmacologia , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Idoso de 80 Anos ou mais
6.
Breast Cancer Res Treat ; 204(1): 133-149, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38057687

RESUMO

PURPOSE: Breast cancer is one of the leading types of cancer diagnosed in women. Despite the improvements in chemotherapeutic cure strategies, drug resistance is still an obstacle leading to disease aggressiveness. The small non-coding RNA molecules, miRNAs, have been implicated recently to be involved as regulators of gene expression through the silencing of mRNA targets that contributed to several cellular processes related to cancer metastasis. Hence, the present study aimed to investigate the beneficial role and mechanism of miRNA-34a-based gene therapy as a novel approach for conquering drug resistance mediated by ATP-binding cassette (ABC) transporters in breast cancer cells, besides exploring the associated invasive behaviors. MATERIAL AND METHODS: Bioinformatics tools were used to predict miRNA ABC transporter targets by tracking the ABC transporter pathway. After the establishment of drug-resistant breast cancer MCF-7 and MDA-MB-231 sublines, cells were transfected with the mimic or inhibitor of miRNA-34a-5p. The quantitative expression of genes involved in drug resistance was performed by QRT-PCR, and the exact ABC transporter target specification interaction was confirmed by dual-luciferase reporter assay. Furthermore, flow cytometric analysis was utilized to determine the ability of miRNA-34a-treated cells against doxorubicin uptake and accumulation in cell cycle phases. The spreading capability was examined by colony formation, migration, and wound healing assays. The apoptotic activity was estimated as well. RESULTS: Our findings firstly discovered the mechanism of miRNA-34a-5p restoration as an anti-drug-resistant molecule that highly significantly attenuates the expression of ABCC1 via the direct targeting of its 3'- untranslated regions in resistant breast cancer cell lines, with a significant increase of doxorubicin influx by MDA-MB-231/Dox-resistant cells. Additionally, the current data validated a significant reduction of metastatic potentials upon miRNA-34a-5p upregulation in both types of breast cancer-resistant cells. CONCLUSION: The ectopic expression of miRNA-34a ameliorates the acquired drug resistance and the migration properties that may eventually lead to improved clinical strategies and outcomes for breast cancer patients. Additionally, miRNA-34a could be monitored as a diagnostic/prognostic biomarker for resistant conditions.


Assuntos
Neoplasias da Mama , MicroRNAs , Feminino , Humanos , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Progressão da Doença , Doxorrubicina/farmacologia , Doxorrubicina/uso terapêutico , Resistencia a Medicamentos Antineoplásicos/genética , Regulação Neoplásica da Expressão Gênica , Células MCF-7 , MicroRNAs/genética , Proteínas Associadas à Resistência a Múltiplos Medicamentos/genética , Proteínas Associadas à Resistência a Múltiplos Medicamentos/metabolismo , Proteínas Associadas à Resistência a Múltiplos Medicamentos/uso terapêutico
7.
Plant Biotechnol J ; 2024 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-39387219

RESUMO

Class 2 Type V-A CRISPR-Cas (Cas12a) nucleases are powerful genome editing tools, particularly effective in A/T-rich genomic regions, complementing the widely used CRISPR-Cas9 in plants. To enhance the utility of Cas12a, we investigate three Cas12a orthologs-Mb3Cas12a, PrCas12a, and HkCas12a-in plants. Protospacer adjacent motif (PAM) requirements, editing efficiencies, and editing profiles are compared in rice. Among these orthologs, Mb3Cas12a exhibits high editing efficiency at target sites with a simpler, relaxed TTV PAM which is less restrictive than the canonical TTTV PAM of LbCas12a and AsCas12a. To optimize Mb3Cas12a, we develop an efficient single transcription unit (STU) system by refining the linker between Mb3Cas12a and CRISPR RNA (crRNA), nuclear localization signal (NLS), and direct repeat (DR). This optimized system enables precise genome editing in rice, particularly for fine-tuning target gene expression by editing promoter regions. Further, we introduced Arginine (R) substitutions at Aspartic acid (D) 172, Asparagine (N) 573, and Lysine (K) 579 of Mb3Cas12a, creating two temperature-tolerant variants: Mb3Cas12a-R (D172R) and Mb3Cas12a-RRR (D172R/N573R/K579R). These variants demonstrate significantly improved editing efficiency at lower temperatures (22 °C and 28 °C) in rice cells, with Mb3Cas12a-RRR showing the best performance. We extend this approach by developing efficient Mb3Cas12a-RRR STU systems in maize and tomato, achieving biallelic mutants targeting single or multiple genes in T0 lines cultivated at 28 °C and 25 °C, respectively. This study significantly expands Cas12a's targeting capabilities in plant genome editing, providing valuable tools for future research and practical applications.

8.
Anal Biochem ; 692: 115571, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38796119

RESUMO

Markers of myocardial injury, such as myoglobin (Mb), are substances swiftly released into the peripheral bloodstream upon myocardial cell injury or altered cardiac activity. During the onset of acute myocardial infarction, patients experience a significant surge in serum Mb levels. Given this, precise detection of Mb is essential, necessitating the development of innovative assays to optimize detection capabilities. This study introduces the synthesis of a three-dimensional hierarchical nanocomposite, Cubic-ZIF67@Au-rGOF-NH2, utilizing aminated reduced graphene oxide and zeolite imidazolium ester framework-67 (ZIF67) as foundational structures. Notably, this novel material, applied in a label-free electrochemical immunosensor, presents a groundbreaking approach for detecting myocardial injury markers. Experimental outcomes revealed ZIF67 and AuNPs exhibit enhanced affinity and growth on the 3D-rGOF-NH2 matrix, thus amplifying electrical conductivity while preserving the inherent electrochemical attributes of ZIF67. As a result, the Cubic-ZIF67@Au-rGOF-NH2 label-free electrochemical immunosensor exhibited a broad detection range and high sensitivity for Mb. The derived standard curve was ΔIp = 16.67552lgC+275.245 (R = 0.993) with a detection threshold of 3.47 fg/ml. Moreover, recoveries of standards spiked into samples ranged between 96.3% and 108.7%. Importantly, the devised immunosensor retained notable selectivity against non-target proteins, proving its potential clinical utility based on exemplary sample analysis performance.


Assuntos
Técnicas Eletroquímicas , Ouro , Grafite , Estruturas Metalorgânicas , Mioglobina , Mioglobina/análise , Técnicas Eletroquímicas/métodos , Grafite/química , Estruturas Metalorgânicas/química , Ouro/química , Humanos , Técnicas Biossensoriais/métodos , Nanocompostos/química , Zeolitas/química , Imidazóis/química , Limite de Detecção , Nanopartículas Metálicas/química
9.
Chemphyschem ; 25(19): e202400488, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-39005001

RESUMO

In a recent paper (ChemPhysChem, 2023, 24, e202200947), based on the results computed using DFT method, the perfect core-shell octahedral configuration Be@B38 and Zn@B38 was reported to be the global minima of the MB38(M=Be and Zn) clusters. However, this paper presents the lower energy structures of MB38(M=Be and Zn) clusters as a quasi-planar configuration, the Be atom is found to reside on the convex surface of the quasi-planar B38 isomer, while the Zn atom tends to be attached to the top three B atoms of the quasi-planar B38 isomer. Our results show that quasi-planar MB38(M=Be and Zn) at DFT method have lower energy than core-shell octahedral configuration M@B38(M=Be and Zn). Natural atomic charges, valence electron density, electron localization function (ELF) analyses identify the MB38(M=Be and Zn) to be charge transfer complexes (Be2+B38 2-and Zn1+B38 1-) and suggest primarily the electrostatic interactions between doped atom and B38 fragment. The photoelectron spectra of the corresponding anionic structures were simulated, providing theoretical basis for future structural identification.

10.
Cell Commun Signal ; 22(1): 161, 2024 03 06.
Artigo em Inglês | MEDLINE | ID: mdl-38448989

RESUMO

BACKGROUND: Breast cancer is the most common cancer in women worldwide. Triple-negative breast cancer (TNBC) is especially aggressive and associated with high metastasis. The aetiology of TNBC is heterogeneous and characterised by multiple different mutations that amongst others cause constitutive and dysregulated MAPK and PI3K signalling. Additionally, in more than 50% of TNBC patients, the epidermal growth factor receptor (EGFR) is overexpressed and constitutively active. The multi-site docking protein Grb2-associated binder 1 (Gab1) is a central signalling hub that connects MAPK and PI3K signalling. METHODS: Expression and activation of members of the Gab1/PI3K/MAPK signalling network were assessed in cells from different breast cancer subtypes. Influence of short- and long-term inhibition of EGFR, MAPK and PI3K on the activation of the Gab1/PI3K/MAPK signalling network as well as on cell viability, proliferation and migration was determined. Additionally, cellular localisation of Gab1 and Gab1 variants in naive cells and cells treated with the above-mentioned inhibitors was investigated. RESULTS: We show that, activation of the Gab1/PI3K/MAPK signalling network is heterogeneous between different breast cancer subtypes. Gab1 phosphorylation and plasma membrane recruitment of Gab1 are dysregulated in the EGFRhigh TNBC cell line MDA-MB-468. While the Gab1/MAPK/PI3K signalling network follows canonical Gab1 signalling in naive MDA-MB-468 cells, Gab1 signalling is changed in cells that acquired resistance towards MAPK and PI3K inhibition. In resistant cells, Gab1 is not located at the plasma membrane despite strong activation of PI3K and MAPK. Furthermore, Gab1 tyrosine phosphorylation is uncoupled from plasma membrane recruitment. CONCLUSION: Our study indicates that Gab1 signalling changes fundamentally during the acquisition of resistance to pharmacological inhibitors. Given the molecular heterogeneity between breast cancer subtypes, the detailed understanding of dysregulated and aberrant signalling is an absolute necessity in order to develop personalised therapies for patients with TNBC.


Breast cancer is very diverse among different patients. Understanding these differences is important for specific and successful treatment of breast cancer patients. About 15% of breast cancer patients have a very severe form of breast cancer called triple negative breast cancer. So far, no specific treatment for these patients exists. Triple-negative breast cancer cells divide without external stimuli as intracellular signalling is constitutively activated in these cells. We show that, in a specific type of triple negative breast cancer, an intracellular signalling network called Gab1/MAPK/PI3K signalling is disturbed. In these breast cancer cells, the Gab1/MAPK/PI3K network is initiated by hyperactive epidermal growth factor receptor (EGFR). In naive untreated breast cancer cells, the EGFR-induced Gab1/MAPK/PI3K network follows the rules described for healthy cells. However, when the cells acquire resistance to pharmacological inhibition of this network, substantial changes in this network happen. This study is the first showing that Gab1 signalling fundamentally changes during resistance development. Understanding the underlying molecular changes during cancer progression is fundamental for future development of personalised therapies for patients with triple negative breast cancer.


Assuntos
Neoplasias de Mama Triplo Negativas , Humanos , Feminino , Transdução de Sinais , Receptores ErbB , Membrana Celular , Fosfatidilinositol 3-Quinases
11.
J Neurooncol ; 168(1): 139-149, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38662151

RESUMO

PURPOSE: Medulloblastoma (MB), a common and heterogeneous posterior fossa tumor in pediatric patients, presents diverse prognostic outcomes. To advance our understanding of MB's intricate biology, the development of novel patient tumor-derived culture MB models with necessary data is still an essential requirement. METHODS: We continuously passaged PUMC-MB1 in vitro in order to establish a continuous cell line. We examined the in vitro growth using Cell Counting Kit-8 (CCK-8) and in vivo growth with subcutaneous and intracranial xenograft models. The xenografts were investigated histopathologically with Hematoxylin and Eosin (HE) staining and immunohistochemistry (IHC). Concurrently, we explored its molecular features using Whole Genome Sequencing (WGS), targeted sequencing, and RNA sequecing. Guided by bioinformatics analysis, we validated PUMC-MB1's drug sensitivity in vitro and in vivo. RESULTS: PUMC-MB1, derived from a high-risk MB patient, displayed a population doubling time (PDT) of 48.18 h and achieved 100% tumor growth in SCID mice within 20 days. HE and Immunohistochemical examination of the original tumor and xenografts confirmed the classification of PUMC-MB1 as a classic MB. Genomic analysis via WGS revealed concurrent MYC and OTX2 amplifications. The RNA-seq data classified it within the Group 3 MB subgroup, while according to the WHO classification, it fell under the Non-WNT/Non-SHH MB. Comparative analysis with D283 and D341med identified 4065 differentially expressed genes, with notable enrichment in the PI3K-AKT pathway. Cisplatin, 4-hydroperoxy cyclophosphamide/cyclophosphamide, vincristine, and dactolisib (a selective PI3K/mTOR dual inhibitor) significantly inhibited PUMC-MB1 proliferation in vitro and in vivo. CONCLUSIONS: PUMC-MB1, a novel Group 3 (Non-WNT/Non-SHH) MB cell line, is comprehensively characterized for its growth, pathology, and molecular characteristics. Notably, dactolisib demonstrated potent anti-proliferative effects with minimal toxicity, promising a potential therapeutic avenue. PUMC-MB1 could serve as a valuable tool for unraveling MB mechanisms and innovative treatment strategies.


Assuntos
Neoplasias Cerebelares , Meduloblastoma , Inibidores de Fosfoinositídeo-3 Quinase , Serina-Treonina Quinases TOR , Animais , Humanos , Camundongos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Neoplasias Cerebelares/tratamento farmacológico , Neoplasias Cerebelares/patologia , Neoplasias Cerebelares/genética , Neoplasias Cerebelares/metabolismo , Meduloblastoma/tratamento farmacológico , Meduloblastoma/patologia , Meduloblastoma/genética , Meduloblastoma/metabolismo , Camundongos SCID , Fosfatidilinositol 3-Quinases/metabolismo , Fosfatidilinositol 3-Quinases/genética , Inibidores de Fosfoinositídeo-3 Quinase/farmacologia , Serina-Treonina Quinases TOR/antagonistas & inibidores , Serina-Treonina Quinases TOR/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
12.
Malar J ; 23(1): 113, 2024 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-38643165

RESUMO

BACKGROUND: Microsporidia MB, an endosymbiont naturally found in Anopheles mosquitoes inhibits transmission of Plasmodium and is a promising candidate for a transmission-blocking strategy that may involve mosquito release. A rapid assessment was carried out to develop insight into sociodemographic factors, public health concerns, and malaria awareness, management, and prevention practices with the willingness to accept and participate in Microsporidia MB-based transmission-blocking strategy to develop an informed stakeholder engagement process. METHODS: The assessment consisted of a survey conducted in two communities in western Kenya that involved administering a questionnaire consisting of structured, semi-structured, and open questions to 8108 household heads. RESULTS: There was an overall high level of willingness to accept (81%) and participate in the implementation of the strategy (96%). Although the willingness to accept was similar in both communities, Ombeyi community was more willing to participate (OR 22, 95% CI 13-36). Women were less willing to accept (OR 0.8, 95% CI 0.7-0.9) compared to men due to fear of increased mosquito bites near homes. Household heads with incomplete primary education were more willing to accept (OR 1.6, 95% CI 01.2-2.2) compared to those educated to primary level or higher. Perceiving malaria as a moderate or low public health issue was also associated with a lower willingness to accept and participate. Experience of > 3 malaria cases in the family over the last six months and knowledge that malaria is transmitted by only mosquito bites, increased the willingness to accept but reduced the willingness to participate. Awareness of malaria control methods based on mosquitoes that cannot transmit malaria increases the willingness to participate. CONCLUSION: The study showed a high level of willingness to accept and participate in a Microsporidia MB-based strategy in the community, which is influenced by several factors such as community, disease risk perception, gender, education level, knowledge, and experience of malaria. Further research will need to focus on understanding the concerns of women, educated, and employed community members, and factors that contribute to the lower disease risk perception. This improved understanding will lead to the development of an effective communication strategy.


Assuntos
Mordeduras e Picadas de Insetos , Malária , Microsporídios , Masculino , Animais , Humanos , Feminino , Quênia , Malária/prevenção & controle , Saúde Pública , Controle de Mosquitos/métodos , Mosquitos Vetores
13.
Cell Biol Int ; 48(2): 162-173, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37818706

RESUMO

For cells to obtain inorganic phosphate, ectoenzymes in the plasma membrane, which contain a catalytic site facing the extracellular environment, hydrolyze phosphorylated molecules. In this study, we show that increased Pi levels in the extracellular environment promote a decrease in ecto-phosphatase activity, which is associated with Pi-induced oxidative stress. High levels of Pi inhibit ecto-phosphatase because Pi generates H2 O2 . Ecto-phosphatase activity is inhibited by H2 O2 , and this inhibition is selective for phospho-tyrosine hydrolysis. Additionally, it is shown that the mechanism of inhibition of ecto-phosphatase activity involves lipid peroxidation. In addition, the inhibition of ecto-phosphatase activity by H2 O2 is irreversible. These findings have new implications for understanding ecto-phosphatase regulation in the tumor microenvironment. H2 O2 stimulated by high Pi inhibits ecto-phosphatase activity to prevent excessive accumulation of extracellular Pi, functioning as a regulatory mechanism of Pi variations in the tumor microenvironment.


Assuntos
Neoplasias da Mama , Peróxido de Hidrogênio , Humanos , Feminino , Peróxido de Hidrogênio/farmacologia , Fosfatos/farmacologia , Fosfatos/metabolismo , Monoéster Fosfórico Hidrolases , Hidrólise , Microambiente Tumoral
14.
Cell Biol Int ; 48(9): 1354-1363, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38894528

RESUMO

Ecto-5'-nucleotidase (CD73) hydrolyses 5'AMP to adenosine and inorganic phosphate. Breast cancer cells (MDA-MB-231) express high CD73 levels, and this enzyme has been found to play a tumour-promoting role in breast cancer. However, no studies have sought to investigate whether CD73 has differential affinity or substrate preferences between noncancerous and cancerous breast cells. In the present study, we aimed to biochemically characterise ecto-5'-nucleotidase in breast cancer cell lines and assess whether its catalytic function and tumour progression are correlated in breast cancer cells. The results showed that compared to nontumoral breast MCF-10A cells, triple-negative breast cancer MDA-MB-231 cells had a higher ecto-5'-nucleotidase expression level and enzymatic activity. Although ecto-5'-nucleotidase activity in the MDA-MB-231 cell line showed no selectivity among monophosphorylated substrates, 5'AMP was preferred by the MCF-10A cell line. Compared to the MCF-10A cell line, the MDA-MB-231 cell line has better hydrolytic ability, lower substrate affinity, and high inhibitory potential after treatment with a specific CD73 inhibitor α,ß­methylene ADP (APCP). Therefore, we demonstrated that a specific inhibitor of the ecto-5-nucleotidase significantly reduced the migratory and invasive capacity of MDA-MB-231 cells, suggesting that ecto-5-nucleotidase activity might play an important role in metastatic progression.


Assuntos
5'-Nucleotidase , Neoplasias de Mama Triplo Negativas , Humanos , 5'-Nucleotidase/metabolismo , Neoplasias de Mama Triplo Negativas/patologia , Neoplasias de Mama Triplo Negativas/metabolismo , Linhagem Celular Tumoral , Feminino , Proteínas Ligadas por GPI/metabolismo , Neoplasias da Mama/patologia , Neoplasias da Mama/metabolismo , Movimento Celular , Adenosina/metabolismo , Adenosina/análogos & derivados
15.
Biomarkers ; 29(6): 376-383, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39234754

RESUMO

BACKGROUND: In Egypt, aluminum phosphide (ALP) is a known lethal poison due to its cardiotoxicity. This study aimed to evaluate the predictive ability of N-terminal pro-B-type natriuretic peptide (NT-proBNP) for mortality in ALP-poisoned patients. METHODS: This prospective study was conducted on patients with ALP poisoning admitted to the Poison Control Center Ain Shams University Hospitals between July and December 2022. Upon admission, all patients were followed up and had their levels of NT-proBNP, troponin I (cTnI), and creatine kinase myocardial band (CK-MB) analyzed. RESULTS: Thirty patients were enrolled in the study and were divided into survivors and non-survivors. The initial NT-proBNP levels were significantly higher among non-survivors in contrast to the initial cTnI and CK-MB levels. The study identified that the best cutoff point of NT-proBNP for predicting mortality was ≥72 pg/ml, with AUC (0.869). CONCLUSION: It can be concluded that NT-proBNP can serve as an early predictor of mortality in ALP poisoning.


Assuntos
Compostos de Alumínio , Biomarcadores , Peptídeo Natriurético Encefálico , Fragmentos de Peptídeos , Fosfinas , Humanos , Peptídeo Natriurético Encefálico/sangue , Fosfinas/intoxicação , Biomarcadores/sangue , Compostos de Alumínio/intoxicação , Fragmentos de Peptídeos/sangue , Feminino , Masculino , Estudos Prospectivos , Adulto , Troponina I/sangue , Egito , Pessoa de Meia-Idade , Creatina Quinase Forma MB/sangue , Intoxicação/mortalidade , Intoxicação/sangue , Intoxicação/diagnóstico , Adulto Jovem , Valor Preditivo dos Testes
16.
Bioorg Med Chem Lett ; 107: 129795, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38750906

RESUMO

Chalcones are chemical scaffolds found in natural products, particularly in plants, and are considered for structural diversity in medicinal chemistry for drug development. Herein, we designed and synthesised novel acetamide derivatives of chalcone, characterizing them using 1H NMR, 13C NMR, HRMS, and IR spectroscopic methods. These derivatives were then screened against human cancer cells for cytotoxicity using the SRB assay. Among the tested derivatives, 7g, with a pyrrolidine group, exhibited better cell growth inhibition activity against triple-negative breast cancer (TNBC) cells. Further assays, including SRB, colony formation, and fluorescent dye-based microscopic analysis, confirmed that 7g significantly inhibited MDA-MB-231 cell proliferation. Furthermore, 7g promoted apoptosis by upregulating cellular reactive oxygen species (ROS) levels and disrupting mitochondrial membrane potential (MMP). Elevated expression of pro-apoptotic proteins (Bax and caspase-3) and a higher Bax/Bcl-2 ratio with downregulation of anti-apoptotic (Bcl-2) protein levels were observed in TNBC cells. The above results suggest that 7g can promote cellular death through apoptotic mechanisms in TNBC cells.


Assuntos
Acetamidas , Antineoplásicos , Apoptose , Proliferação de Células , Desenho de Fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Neoplasias de Mama Triplo Negativas , Humanos , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/patologia , Neoplasias de Mama Triplo Negativas/metabolismo , Antineoplásicos/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Relação Estrutura-Atividade , Proliferação de Células/efeitos dos fármacos , Acetamidas/farmacologia , Acetamidas/síntese química , Acetamidas/química , Apoptose/efeitos dos fármacos , Estrutura Molecular , Linhagem Celular Tumoral , Chalconas/farmacologia , Chalconas/química , Chalconas/síntese química , Relação Dose-Resposta a Droga , Chalcona/farmacologia , Chalcona/química , Chalcona/síntese química , Espécies Reativas de Oxigênio/metabolismo , Potencial da Membrana Mitocondrial/efeitos dos fármacos
17.
Nanotechnology ; 35(26)2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38527359

RESUMO

A novel, rapid, and facile method for one-step sonoelectrochemical synthesis of zinc oxide nanoparticles (UEZ) was introduced in this study. The optimum operating parameters have been selected at a voltage of 7.5 V, KCl concentration of 0.5 M, and the reaction time of 60 min. The as-prepared UEZ were characterized by XRD, SEM, and HRTEM. It was found that the UEZ has a hexagonal wurtzite structure with high crystalline quality, good purity, a size range of 30-100 nm, and good photocatalytic degradation of methylene blue. This work provides a facile route for large-scale synthesizing ZnO nanoparticles via anodization.

18.
Nanotechnology ; 35(33)2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38746972

RESUMO

Traditional therapies often struggle with specificity and resistance in case of cancer treatments. It is therefore important to investigate new approaches for cancer treatment based on nanotechnology. Zinc oxide nanoparticles (ZnONPs) are known to exhibit anti-cancer properties by inducing oxidative stress, apoptosis, and cell cycle arrest. Methotrexate (MTX) a known anti-folate shows specificity to folate receptors and interrupts healthy functioning of cells. This study proposes the use of previously characterized biocompatible Methotrexate loaded Zinc oxide nanoparticles (MTX-ZnONPs) as a dual action therapeutic strategy against breast cancer cell lines, MCF-7 (MTX-sensitive) and MDA-MB-231 (MTX-resistant). To elucidate the cytotoxicity mechanism of MTX-ZnONPs an in depthIn vitrostudy was carried out.In vitroassays, including cell cycle analysis, apoptosis assay, and western blot analysis to study the protein expression were performed. Results of these assays, further supported the anti-cancer activity of MTX-ZnONPs showing apoptotic and necrotic activity in MCF-7 and MDA-MB-231 cell line respectively.In vivoacute oral toxicity study to identify the LD50in animals revealed no signs of toxicity and mortality up to 550 mg kg-1body weight of animal, significantly higher LD50values than anticipated therapeutic levels and safety of the synthesized nanosystem. The study concludes that MTX-ZnONPs exhibit anti-cancer potential against breast cancer cells offering a promising strategy for overcoming resistance.


Assuntos
Apoptose , Neoplasias da Mama , Metotrexato , Óxido de Zinco , Metotrexato/farmacologia , Metotrexato/química , Metotrexato/administração & dosagem , Humanos , Óxido de Zinco/química , Óxido de Zinco/farmacologia , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Feminino , Células MCF-7 , Apoptose/efeitos dos fármacos , Animais , Linhagem Celular Tumoral , Nanopartículas/química , Antineoplásicos/farmacologia , Antineoplásicos/química , Sobrevivência Celular/efeitos dos fármacos
19.
Nanotechnology ; 35(47)2024 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-39168138

RESUMO

The objective of this study is to develop an efficient, easily recoverable membrane-based photocatalyst for removing organic pollutants from aqueous solutions. This study documents the effective synthesis of a novel composite photocatalyst comprising WO3/g-C3N4(WCN) loaded onto cellulose acetate (CA). The physicochemical properties of the synthesized nanocomposites were validated using a range of techniques, including Fourier transform infrared spectroscopy, x-ray diffraction, scanning electron microscopy (SEM), energy-dispersive x-ray spectroscopy, and UV-visible diffuse reflectance spectroscopy. SEM analysis revealed that the WCN particles exhibited a well-decorated arrangement on the CA surface in the form of spherical particles. The successfully synthesized film was utilized as a potential adsorbent for removing organic pollutants such as Rhodamine B (Rh-B) and Methylene blue (MB) from aqueous solutions under UV light illumination. The results showcased the significant potential of the WCN@CA nanocomposite, achieving a remarkable 83% and 85% efficiency in eliminating Rh-B and MB. The pseudo-first-order kinetic models were found to be appropriate for both dye adsorption onto the WCN@CA nanocomposite. The WCN@CA catalyst, capable of being reused five times without significant loss of efficiency, shows great potential for decomposing toxic organic pollutants. The novelty of this work lies in the innovative combination of WCN with CA, resulting in a highly efficient and reusable photocatalyst for environmental remediation.

20.
Mol Biol Rep ; 51(1): 646, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38727931

RESUMO

BACKGROUND: Breast cancer (BC) is one of the most common cancers in the world. Despite the many advances that have been made in treating patients, many patients are still resistant to treatment. CD44 is one of the surface glycoproteins of BC cells that plays an important role in the proliferation of these cells and inhibition of their apoptosis. Therefore, targeting it can be a treatment way for BC patients. METHODS: In this study, the effect of anti-CD44 siRNA on the proliferation, apoptosis, and migration rate of MDA-MB-231 and 4T1 cells was investigated. The techniques used in this study were MTT assay, RT-PCR, and flow cytometry. RESULTS: The apoptosis and proliferation rates in CD44 siRNA-treated cells were higher and lower, respectively, compared to untreated cells. Also, cell migration was less in treated cells compared to untreated cells. CD44 siRNA also decreased the expression of CXCR4, c-myc, Vimentin, ROCK, and MMP-9. CONCLUSION: Finally, CD44 targeting can be a good treatment option to make BC cells more sensitive to apoptosis.


Assuntos
Apoptose , Neoplasias da Mama , Receptores de Hialuronatos , RNA Interferente Pequeno , Feminino , Humanos , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Sobrevivência Celular , Regulação Neoplásica da Expressão Gênica , Receptores de Hialuronatos/antagonistas & inibidores , Metaloproteinase 9 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/genética , Receptores CXCR4/genética , Receptores CXCR4/metabolismo , RNA Interferente Pequeno/genética , Vimentina/metabolismo , Vimentina/genética
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