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1.
Int J Mol Sci ; 25(2)2024 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-38255835

RESUMO

This study aimed to identify microRNAs (miRNAs) whose expression levels are altered by high-risk human papillomavirus (HR-HPV) infection in women with epithelial ovarian neoplasms. MiRNA expression was quantified by real-time polymerase chain reaction, while HR-HPV DNA was quantified using digital-droplet PCR. Analysis of 11 miRNAs demonstrated significantly lower hsa-miR-25-5p expression in HPV-infected compared to uninfected ovarian tissues (p = 0.0405), while differences in miRNA expression in corresponding serum were statistically insignificant. The expression of hsa-miR-218-5p in ovarian tumors was significantly higher in high-grade serous ovarian carcinoma (HGSOC) cases than in other neoplasms (p = 0.0166). In addition, hsa-miR-218-5p was significantly upregulated, whereas hsa-miR-191-5p was significantly downregulated in tissues with stage III/IV FIGO (p = 0.0009 and p = 0.0305, respectively). Using unsupervised clustering, we identified three unique patient groups with significantly varied frequencies of HPV16/18-positive samples and varied miRNA expression profiles. In multivariate analysis, high expression of hsa-miR-16-5p was an independent prognostic factor for poor overall survival (p = 0.0068). This preliminary analysis showed the changes in miRNA expression in ovarian neoplasms during HPV infection and those collected from HGSOCs or patients with advanced disease. This prospective study can provide new insights into the pathogenesis of ovarian neoplasms and host-virus interactions.


Assuntos
MicroRNAs , Neoplasias Ovarianas , Infecções por Papillomavirus , Humanos , Feminino , Infecções por Papillomavirus/complicações , Infecções por Papillomavirus/genética , Papillomavirus Humano 16 , Estudos Prospectivos , Papillomavirus Humano 18 , MicroRNAs/genética , Neoplasias Ovarianas/genética
2.
Int J Mol Sci ; 22(3)2021 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-33499077

RESUMO

Two immortalized brain microvascular endothelial cell lines (hCMEC/D3 and RBE4, of human and rat origin, respectively) were applied as an in vitro model of cellular elements of the blood-brain barrier in a nanotoxicological study. We evaluated the impact of CdSe/ZnS core-shell-type quantum dot nanoparticles on cellular homeostasis, using gold nanoparticles as a largely bioorthogonal control. While the investigated nanoparticles had surprisingly negligible acute cytotoxicity in the evaluated models, a multi-faceted study of barrier-related phenotypes and cell condition revealed a complex pattern of homeostasis disruption. Interestingly, some features of the paracellular barrier phenotype (transendothelial electrical resistance, tight junction protein gene expression) were improved by exposure to nanoparticles in a potential hormetic mechanism. However, mitochondrial potential and antioxidant defences largely collapsed under these conditions, paralleled by a strong pro-apoptotic shift in a significant proportion of cells (evidenced by apoptotic protein gene expression, chromosomal DNA fragmentation, and membrane phosphatidylserine exposure). Taken together, our results suggest a reactive oxygen species-mediated cellular mechanism of blood-brain barrier damage by quantum dots, which may be toxicologically significant in the face of increasing human exposure to this type of nanoparticles, both intended (in medical applications) and more often unintended (from consumer goods-derived environmental pollution).


Assuntos
Barreira Hematoencefálica/metabolismo , Compostos de Cádmio/química , Nanopartículas/química , Pontos Quânticos , Compostos de Selênio/química , Sulfetos/química , Compostos de Zinco/química , Animais , Apoptose , Membrana Celular/metabolismo , Sobrevivência Celular , Cromossomos/metabolismo , Fragmentação do DNA , Poluentes Ambientais/química , Homeostase , Humanos , Potenciais da Membrana , Mitocôndrias/metabolismo , Oxirredução , Fenótipo , Fosfatidilserinas/química , Ratos , Espécies Reativas de Oxigênio/metabolismo , Junções Íntimas
3.
Int J Mol Sci ; 22(24)2021 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-34947988

RESUMO

Recently, we have shown the molecular basis for lactate sensing by cervical epithelial cells resulting in enhanced DNA repair processes through DNA-PKcs regulation. Interestingly, DNA-PKcs is indispensable for proper retroviral DNA integration in the cell host genome. According to recent findings, the mucosal epithelium can be efficiently transduced by retroviruses and play a pivotal role in regulating viral release by cervical epithelial cells. This study examined the effects of lactate on lentiviral transduction in cervical cancer cells (HeLa, CaSki, and C33A) and model glioma cell lines (DNA-PKcs proficient and deficient). Our study showed that L- and D-lactate enhanced DNA-PKcs presence in nuclear compartments by between 38 and 63%, which corresponded with decreased lentiviral transduction rates by between 15 and 36%. Changes in DNA-PKcs expression or its inhibition with NU7441 also greatly affected lentiviral transduction efficacy. The stimulation of cells with either HCA1 agonist 3,5-DHBA or HDAC inhibitor sodium butyrate mimicked, in part, the effects of L-lactate. The inhibition of lactate flux by BAY-8002 enhanced DNA-PKcs nuclear localization which translated into diminished lentiviral transduction efficacy. Our study suggests that L- and D-lactate present in the uterine cervix may play a role in the mitigation of viral integration in cervical epithelium and, thus, restrict the viral oncogenic and/or cytopathic potential.


Assuntos
Proteína Quinase Ativada por DNA/metabolismo , Glioma/virologia , Ácido Láctico/farmacologia , Lentivirus/fisiologia , Neoplasias do Colo do Útero/virologia , Benzoatos/farmacologia , Ácido Butírico/farmacologia , Linhagem Celular Tumoral , Núcleo Celular/metabolismo , Cromonas/farmacologia , Feminino , Glioma/metabolismo , Células HeLa , Humanos , Lentivirus/efeitos dos fármacos , Morfolinas/farmacologia , Transdução Genética , Neoplasias do Colo do Útero/metabolismo
4.
Breast J ; 26(1): 39-41, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31971345

RESUMO

Breast reconstruction has evolved in the last 25 years to provide women with better autologous and implant-based options. The general trends of breast reconstruction have shifted to skin and nipple-areolar complex preservation, resulting in improved aesthetics and patient satisfaction. Autologous reconstruction has made a dramatic movement toward microsurgical reconstruction by free tissue transfer and has addressed lymphedema and breast sensation. Using the patient's own tissues, several aesthetic refinements have led to optimizing the cosmetic appearance of the reconstructed breast. Implant-based reconstruction has improved with the invention of form-stable silicone implants, acellular dermal matrix, and fat grafting. These positive trends will continue into the future. We hope that all women with a diagnosis of breast cancer will have the option of a consultation with a reconstructive plastic surgeon, ideally prior to undergoing resective surgery, to ensure they are aware of all reconstructive options to maximize their reconstructive result.


Assuntos
Mamoplastia/história , Neoplasias da Mama/cirurgia , Feminino , História do Século XX , História do Século XXI , Humanos , Mamoplastia/tendências , Estados Unidos
5.
J Craniofac Surg ; 31(7): e710-e714, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32604292

RESUMO

INTRODUCTION: The free fibula flap (FFF) is a preferred option for adult mandibular reconstruction. Due to skeletal immaturity, its routine use in pediatric patients remains in question. Inconsistencies regarding the ability of the FFF to grow in concordance with the patients' natural growth currently exist in the literature. The purpose of this report is to quantify mandibular growth in a young patient undergoing partial hemi-mandibular reconstruction with a FFF utilizing advanced three-dimensional software. METHODS: A 2-year old underwent left hemi-mandibular reconstruction with a FFF following resection of a desmoid tumor. The condyle was preserved. Using 3D software, changes in mandibular growth and morphology were evaluated based on preoperative (2.1 years old) and postoperative (2.5 years and 5.2 years old) computed tomography imaging. RESULTS: Mandibular growth occurred throughout the mandible in both postoperative evaluations. Greatest growth was seen in the ramus height. Fibula growth was also seen when comparing measurements to the virtual surgical planning guide. A novel parts comparison analysis revealed the greatest growth potential occurred at the condyle. CONCLUSION: Providing an objective evaluation using 3D software, we have demonstrated growth throughout the reconstructed mandible, with greatest growth occurring at the preserved condyle. Despite scientific limitations of our study, the potential for mandibular growth appears to remain after FFF reconstruction, offering successful functional and cosmetic outcomes.


Assuntos
Fíbula/cirurgia , Mandíbula/cirurgia , Reconstrução Mandibular , Pré-Escolar , Feminino , Fíbula/diagnóstico por imagem , Retalhos de Tecido Biológico , Humanos , Mandíbula/diagnóstico por imagem , Mandíbula/transplante , Software , Tomografia Computadorizada por Raios X
6.
Int J Mol Sci ; 21(24)2020 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-33321722

RESUMO

Doxorubicin (DOX) is an effective antineoplastic drug against many solid tumors and hematological malignancies. However, the clinical use of DOX is limited, because of its unspecific mode of action. Since leukemia cells overexpress transferrin (Tf) receptors on their surface, we proposed doxorubicin-transferrin (DOX-Tf) conjugate as a new vehicle to increase drug concentration directly in cancer cells. The data obtained after experiments performed on K562 and CCRF-CEM human leukemia cell lines clearly indicate severe cytotoxic and genotoxic properties of the conjugate drug. On the other hand, normal peripheral blood mononuclear cells (PBMCs) were more resistant to DOX-Tf than to DOX. In comparison to free drug, we observed that Tf-bound DOX induced apoptosis in a TRAIL-dependent manner and caused DNA damage typical of programmed cell death. These fatal hallmarks of cell death were confirmed upon morphological observation of cells incubated with DOX or DOX-Tf. Studies of expression of TNF-α, IL-4, and IL-6 at the mRNA and protein levels revealed that the pro-inflammatory response plays an important role in the toxicity of the conjugate. Altogether, the results demonstrated here describe a mechanism of the antitumor activity of the DOX-Tf conjugate.


Assuntos
Antineoplásicos/farmacologia , Apoptose , Dano ao DNA , Doxorrubicina/análogos & derivados , Leucemia/metabolismo , Transferrina/análogos & derivados , Antineoplásicos/química , Células Cultivadas , Doxorrubicina/farmacologia , Humanos , Interleucina-4/genética , Interleucina-4/metabolismo , Interleucina-6/genética , Interleucina-6/metabolismo , Células K562 , Monócitos/efeitos dos fármacos , Monócitos/metabolismo , Transferrina/farmacologia , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo
7.
Cell Commun Signal ; 13: 36, 2015 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-26208712

RESUMO

BACKGROUND: The consideration of lactate as an active metabolite is a newly emerging and attractive concept. Recently, lactate has been reported to regulate gene transcription via the inhibition of histone deacetylases (HDACs) and survival of cancer cells via hydroxycarboxylic acid receptor 1 (HCAR1). This study examined the role of L- and D-lactate in the DNA damage response in cervical cancer cells. METHODS: Three cervical cancer cell lines were examined: HeLa, Ca Ski and C33A. The inhibitory activity of lactate on HDACs was analysed using Western blot and biochemical methods. The lactate-mediated stimulation of DNA repair and cellular resistance to neocarzinostatin, doxorubicin and cisplatin were studied using γ-H2AX, comet and clonogenic assays. HCAR1 and DNA repair gene expression was quantified by real-time PCR. DNA-PKcs activity and HCAR1 protein expression were evaluated via immunocytochemistry and Western blot, respectively. HCAR1 activation was investigated by measuring intracellular cAMP accumulation and Erk phosphorylation. HCAR1 expression was silenced using shRNA. RESULTS: L- and D-lactate inhibited HDACs, induced histone H3 and H4 hyperacetylation, and decreased chromatin compactness in HeLa cells. Treating cells with lactate increased LIG4, NBS1, and APTX expression by nearly 2-fold and enhanced DNA-PKcs activity. Based on γ-H2AX and comet assays, incubation of cells in lactate-containing medium increased the DNA repair rate. Furthermore, clonogenic assays demonstrated that lactate mediates cellular resistance to clinically used chemotherapeutics. Western blot and immunocytochemistry showed that all studied cell lines express HCAR1 on the cellular surface. Inhibiting HCAR1 function via pertussis toxin pretreatment partially abolished the effects of lactate on DNA repair. Down-regulating HCAR1 decreased the efficiency of DNA repair, abolished the cellular response to L-lactate and decreased the effect of D-lactate. Moreover, HCAR1 shRNA-expressing cells produced significantly lower mRNA levels of monocarboxylate transporter 4. Finally, the enhancement of DNA repair and cell survival by lactate was suppressed by pharmacologically inhibiting monocarboxylate transporters using the inhibitor α-cyano-4-hydroxycinnamic acid (α-CHCA). CONCLUSIONS: Our data indicate that L- and D-lactate present in the uterine cervix may participate in the modulation of cellular DNA damage repair processes and in the resistance of cervical carcinoma cells to anticancer therapy.


Assuntos
Reparo do DNA , Resistencia a Medicamentos Antineoplásicos , Histona Desacetilases/metabolismo , Ácido Láctico/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Neoplasias do Colo do Útero/tratamento farmacológico , Neoplasias do Colo do Útero/metabolismo , Acetilação , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Colo do Útero/efeitos dos fármacos , Colo do Útero/metabolismo , Cisplatino/farmacologia , Quebras de DNA de Cadeia Dupla/efeitos dos fármacos , Doxorrubicina/farmacologia , Feminino , Regulação Neoplásica da Expressão Gênica , Células HeLa , Histonas/genética , Histonas/metabolismo , Humanos , Transportadores de Ácidos Monocarboxílicos/metabolismo , Interferência de RNA , RNA Interferente Pequeno/genética , Receptores Acoplados a Proteínas G/genética , Neoplasias do Colo do Útero/genética , Zinostatina/farmacologia
8.
Nat Genet ; 56(4): 652-662, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38548988

RESUMO

Here we use single-cell RNA sequencing to compile a human breast cell atlas assembled from 55 donors that had undergone reduction mammoplasties or risk reduction mastectomies. From more than 800,000 cells we identified 41 cell subclusters across the epithelial, immune and stromal compartments. The contribution of these different clusters varied according to the natural history of the tissue. Age, parity and germline mutations, known to modulate the risk of developing breast cancer, affected the homeostatic cellular state of the breast in different ways. We found that immune cells from BRCA1 or BRCA2 carriers had a distinct gene expression signature indicative of potential immune exhaustion, which was validated by immunohistochemistry. This suggests that immune-escape mechanisms could manifest in non-cancerous tissues very early during tumor initiation. This atlas is a rich resource that can be used to inform novel approaches for early detection and prevention of breast cancer.


Assuntos
Proteína BRCA1 , Neoplasias da Mama , Adulto , Feminino , Gravidez , Humanos , Proteína BRCA1/genética , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Proteína BRCA2/genética , Genes BRCA2 , Mutação em Linhagem Germinativa
9.
Sci Immunol ; 9(95): eade2094, 2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38787961

RESUMO

Immunotherapy advances have been hindered by difficulties in tracking the behaviors of lymphocytes after antigen signaling. Here, we assessed the behavior of T cells active within tumors through the development of the antigen receptor signaling reporter (AgRSR) mouse, fate-mapping lymphocytes responding to antigens at specific times and locations. Contrary to reports describing the ready egress of T cells out of the tumor, we find that intratumoral antigen signaling traps CD8+ T cells in the tumor. These clonal populations expand and become increasingly exhausted over time. By contrast, antigen-signaled regulatory T cell (Treg) clonal populations readily recirculate out of the tumor. Consequently, intratumoral antigen signaling acts as a gatekeeper to compartmentalize CD8+ T cell responses, even within the same clonotype, thus enabling exhausted T cells to remain confined to a specific tumor tissue site.


Assuntos
Linfócitos T CD8-Positivos , Transdução de Sinais , Animais , Linfócitos T CD8-Positivos/imunologia , Camundongos , Transdução de Sinais/imunologia , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Antígenos de Neoplasias/imunologia , Neoplasias/imunologia
11.
Beilstein J Org Chem ; 9: 1517-25, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23946851

RESUMO

A method for the synthesis of N-aryl-C-nitroazoles is presented. A coupling reaction between variously substituted arylboronic acids and 3(5)-nitro-1H-pyrazole catalyzed by copper salt has been carried out in methanol in the presence of sodium hydroxide to afford the desired N-aryl-C-nitroazoles in good yields. This synthetic route has also been successfully applied to obtain N-phenyl derivatives of 4-nitropyrazole, 2-nitroimidazole, 4(5)-nitroimidazole and 3-nitro-1,2,4-triazole.

12.
Cells ; 12(16)2023 08 11.
Artigo em Inglês | MEDLINE | ID: mdl-37626862

RESUMO

The low distribution of hydrophobic anticancer drugs in patients is one of the biggest limitations during conventional chemotherapy. SDS-based polyelectrolyte multicore nanocarriers (NCs) prepared according to the layer by layer (LbL) procedure can release paclitaxel (PTX), and selectively kill cancer cells. Our main objective was to verify the antitumor properties of PTX-loaded NCs and to examine whether the drug encapsulated in these NCs retained its cytotoxic properties. The cytotoxicity of the prepared nanosystems was tested on MCF-7 and MDA-MB-231 tumour cells and the non-cancerous HMEC-1 cell line in vitro. Confocal microscopy, spectrophotometry, spectrofluorimetry, flow cytometry, and RT PCR techniques were used to define the typical hallmarks of apoptosis. It was demonstrated that PTX encapsulated in the tested NCs exhibited similar cytotoxicity to the free drug, especially in the triple negative breast cancer model. Moreover, SDS/PLL/PTX and SDS/PLL/PGA/PTX significantly reduced DNA synthesis. In addition, PTX-loaded NCs triggered apoptosis and upregulated the transcription of Bax, AIF, cytochrome-c, and caspase-3 mRNA. Our data demonstrate that these novel polyelectrolyte multicore NCs coated with PLL or PLL/PGA are good candidates for delivering PTX. Our discoveries have prominent implications for the possible choice of newly synthesized, SDS-based polyelectrolyte multicore NCs in different anticancer therapeutic applications.


Assuntos
Neoplasias da Mama , Nanopartículas , Paclitaxel , Dodecilsulfato de Sódio , Paclitaxel/administração & dosagem , Humanos , Linhagem Celular Tumoral , Neoplasias da Mama/tratamento farmacológico , Nanopartículas/administração & dosagem , Nanopartículas/química , Dodecilsulfato de Sódio/administração & dosagem , Eletrólitos/química , Apoptose/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos
13.
Pol J Microbiol ; 72(4): 491-506, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-38103008

RESUMO

One of the most relevant and pathogenic groups among the rapidly growing mycobacteria (RGM) is Mycobacterium abscessus complex (MABC) that includes three subspecies: M. abscessus subsp. abscessus, M. abscessus subsp. bolletii, and M. abscessus subsp. massiliense. The aim of this study was the analysis of prevalence of MABC among other non-tuberculous mycobacteria isolated from patients in the Malopolska Region of Poland, between 2018 and 2021, as well as determination of their subspecies and molecular mechanisms of resistance to macrolides and aminoglycosides. The incidence of MABC was 5,4% (12/223). Eight strains were classified as M. abscessus subsp. abscessus, three as M. abscessus subsp. massiliense and one M. abscessus subsp. bolletii. Molecular analysis showed resistance to macrolides for eight strains of M. abscessus subsp. abscessus associated with erm(41)T28 gene mutations. One strain of M. abscessus subsp. abscessus showed resistance to macrolides (two mutations simultaneously: in erm(41)T28 and rrl genes) and aminoglycosides (point mutation in rrs gene). One strain of M. abscessus subs. bolletii was resistant to macrolides (erm(41)T28 mutation), whereas presented no mutations for aminoglycosides. M. abscessus subsp. massiliense reveal no mutations. High clarithromycin resistance of M. abscessus, determines the urgent need for susceptibility-based treatment. Molecular determination of resistance mechanisms to aminoglycosides and macrolides enables fast and accurate targeted treatment implementation.


Assuntos
Macrolídeos , Mycobacterium abscessus , Humanos , Macrolídeos/farmacologia , Mycobacterium abscessus/genética , Aminoglicosídeos/farmacologia , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Claritromicina , Testes de Sensibilidade Microbiana , Farmacorresistência Bacteriana/genética
14.
Pol J Microbiol ; 72(1): 69-77, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36929889

RESUMO

Candida albicans remains the most common species isolated from women with vulvovaginal candidiasis. However, closely related species such as Candida africana and Candida dubliniensis may also occur, although they are often misidentified. The aim of the study was to confirm the phenotypic identification of C. albicans and its closely related species isolated from women with genital tract infections by amplification of the hwp1 (hyphal wall protein 1) gene in a PCR assay. We report a detailed molecular identification of C. albicans and its closely related species among 326 patients in the Malopolska region, Poland. Initial phenotypic identifications were confirmed by amplification of the hwp1 gene. Based on molecular analysis, we revealed 307 strains (94.17%) as C. albicans and 17 as C. dubliniensis (5.22%). No strain of C. africana was detected. Two patients h ad co-infection with C. albicans and C. dubliniensis (0.61%). A PCR assay targeting the hwp1 gene was reliable for correctly identifying species among the C. albicans complex.


Assuntos
Candida albicans , Candidíase Vulvovaginal , Humanos , Feminino , Candida albicans/genética , Candidíase Vulvovaginal/epidemiologia , Candidíase Vulvovaginal/genética , Prevalência , Amplificação de Genes , Polônia/epidemiologia
15.
Cells ; 11(19)2022 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-36231099

RESUMO

Ovarian cancer (OC) is one of the most common cancers threatening women's lives around the world. Epithelial ovarian tumors represent the most common ovarian neoplasms. Most OC patients are diagnosed at the advanced stage, and there is an urgent need to identify novel biomarkers of the disease. Single-nucleotide polymorphisms (SNPs) in TLR genes may serve as crucial markers of cancer susceptibility. We investigated the frequency of TLR polymorphisms in a group of 200 women, including 70 with OC. Four SNPs, two each in TLR4 (rs4986790 and rs4986791) and TLR9 (rs187084 and rs5743836), were analyzed using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). The digested fragments were separated and identified by multicapillary electrophoresis. The load quantification of human papillomavirus (HPV) types 16/18 was determined using a digital droplet PCR method. We found an increased frequency of heterozygous genotype and minor allele of the TLR4 rs4986790 SNP in women with OC compared with healthy controls, and this result remained highly significant after Bonferroni's correction for multiple testing (p < 0.0001). No evidence of linkage disequilibrium was found with any of the examined TLR SNPs. The findings suggest that the TLR4 Asp299Gly polymorphism could be a genetic risk factor for the development of OC.


Assuntos
Neoplasias Ovarianas , Receptor 4 Toll-Like , Feminino , Humanos , Biomarcadores , Carcinoma Epitelial do Ovário/genética , Predisposição Genética para Doença , Genótipo , Neoplasias Ovarianas/genética , Polimorfismo de Nucleotídeo Único/genética , Receptor 4 Toll-Like/genética , Receptor Toll-Like 9/genética
16.
Elife ; 112022 12 16.
Artigo em Inglês | MEDLINE | ID: mdl-36525288

RESUMO

Tumour heterogeneity is thought to be a major barrier to successful cancer treatment due to the presence of drug resistant clonal lineages. However, identifying the characteristics of such lineages that underpin resistance to therapy has remained challenging. Here, we utilise clonal transcriptomics with WILD-seq; Wholistic Interrogation of Lineage Dynamics by sequencing, in mouse models of triple-negative breast cancer (TNBC) to understand response and resistance to therapy, including BET bromodomain inhibition and taxane-based chemotherapy. These analyses revealed oxidative stress protection by NRF2 as a major mechanism of taxane resistance and led to the discovery that our tumour models are collaterally sensitive to asparagine deprivation therapy using the clinical stage drug L-asparaginase after frontline treatment with docetaxel. In summary, clonal transcriptomics with WILD-seq identifies mechanisms of resistance to chemotherapy that are also operative in patients and pin points asparagine bioavailability as a druggable vulnerability of taxane-resistant lineages.


Cancer begins when a cell multiplies again and again to form a tumour. By the time that tumour measures a centimetre across, it can contain upwards of a hundred million cells. And even though they all came from the same ancestor, they are far from identical. The tumour's family tree has many branches, and each one responds differently to treatment. If some are susceptible to a drug the cells die, the tumour shrinks, and the therapy will appear to be successful. But, if even a small number of cancer cells survive, they will regrow, often more persistently, causing a relapse. Identifying resistant cells, their characteristics, and how to kill them has been challenging due to a lack of good animal models. One way to keep track of a cancer family tree is to insert so-called genetic barcodes into the ancestral cells. As the tumour grows, the cells will pass the barcodes to their descendants. Scientists do this by using viruses that naturally paste their genes into the cells they infect. Applying this technique to an animal model of cancer could reveal which genes allow some cells to survive, and how to overcome them. Wild, Cannell et al. developed a genetic barcoding system called WILD-seq and used it to track all the cells in a mouse tumour. The mice received the same drugs used to treat patients with breast cancer. By scanning the genetic barcodes using recently developed single cell sequencing technologies, Wild, Cannell et al. were able to identify and count each type of cancer cell and work out which genes they were using. This revealed which cells the standard treatment could not kill and exposed their genetic weaknesses. Wild, Cannell et al. used this information to target the cells with a drug currently used to treat leukaemia. The drug identified by this new genetic barcoding approach is already licensed for use in humans. Further investigation could reveal whether it might help to shrink breast tumours that do not respond to standard therapy. Similar experiments could uncover more information about how other types of tumour evolve too.


Assuntos
Resistencia a Medicamentos Antineoplásicos , Neoplasias de Mama Triplo Negativas , Humanos , Camundongos , Animais , Resistencia a Medicamentos Antineoplásicos/genética , Proteínas Nucleares , Transcriptoma , Asparagina , Fatores de Transcrição , Neoplasias de Mama Triplo Negativas/patologia , Taxoides/farmacologia , Taxoides/uso terapêutico
17.
Sci Rep ; 12(1): 8082, 2022 05 16.
Artigo em Inglês | MEDLINE | ID: mdl-35577836

RESUMO

Swab, RT-qPCR tests remain the gold standard of diagnostics of SARS-CoV-2 infections. These tests are costly and have limited throughput. We developed a 3-gene, seminested RT-qPCR test with SYBR green-based detection designed to be oversensitive rather than overspecific for high-throughput diagnostics of populations. This two-tier approach depends on decentralized self-collection of saliva samples, pooling, 1st-tier testing with highly sensitive screening test and subsequent 2nd-tier testing of individual samples from positive pools with the IVD test. The screening test was able to detect five copies of the viral genome in 10 µl of isolated RNA with 50% probability and 18.8 copies with 95% probability and reached Ct values that were highly linearly RNA concentration-dependent. In the side-by-side comparison, the screening test attained slightly better results than the commercially available IVD-certified RT-qPCR diagnostic test DiaPlexQ (100% specificity and 89.8% sensitivity vs. 100% and 73.5%, respectively). Testing of 1475 individual clinical samples pooled in 374 pools of four revealed 0.8% false positive pools and no false negative pools. In weekly prophylactic testing of 113 people within 6 months, a two-tier testing approach enabled the detection of 18 infected individuals, including several asymptomatic individuals, with substantially lower cost than individual RT-PCR testing.


Assuntos
COVID-19 , Epidemias , COVID-19/diagnóstico , COVID-19/epidemiologia , Humanos , RNA , RNA Viral/genética , SARS-CoV-2/genética , Saliva , Sensibilidade e Especificidade
18.
Sci Adv ; 8(7): eabj8618, 2022 02 18.
Artigo em Inglês | MEDLINE | ID: mdl-35171685

RESUMO

Platelet deficiency, known as thrombocytopenia, can cause hemorrhage and is treated with platelet transfusions. We developed a system for the production of platelet precursor cells, megakaryocytes, from pluripotent stem cells. These cultures can be maintained for >100 days, implying culture renewal by megakaryocyte progenitors (MKPs). However, it is unclear whether the MKP state in vitro mirrors the state in vivo, and MKPs cannot be purified using conventional surface markers. We performed single-cell RNA sequencing throughout in vitro differentiation and mapped each state to its equivalent in vivo. This enabled the identification of five surface markers that reproducibly purify MKPs, allowing us insight into their transcriptional and epigenetic profiles. Last, we performed culture optimization, increasing MKP production. Together, this study has mapped parallels between the MKP states in vivo and in vitro and allowed the purification of MKPs, accelerating the progress of in vitro-derived transfusion products toward the clinic.


Assuntos
Células-Tronco Pluripotentes Induzidas , Células-Tronco Pluripotentes , Plaquetas , Diferenciação Celular , Megacariócitos
19.
Cell Mol Neurobiol ; 31(7): 1103-11, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21618049

RESUMO

Ischemia-reperfusion leads to increased levels at the blood-brain barrier of the multidrug efflux transporter, P-glycoprotein that provides protection to the brain by limiting access of unwanted substances. This is coincident with the production of nitric oxide. This present study using immortalized rat brain endothelial cells (GPNTs) examines whether following hypoxia-reoxygenation, nitric oxide contributes to the alterations in P-glycoprotein levels. After 6 h of hypoxia, both nitric oxide and reactive oxygen species, detected intracellularly using fluorescent monitoring dyes, were produced in the subsequent reoxygenation phase coincident with increased P-glycoprotein. The evidence that nitric oxide can directly affect P-glycoprotein expression was sought by applying S-nitroso-N-acetyl-DL: -penicillamine that as shown increased the nitric oxide generation. Sodium nitroprusside, though more effective at increasing P-glycoprotein expression, appeared to produce different reactive species. Real time RT-PCR analysis revealed the predominant form of nitric oxide synthase in these cells to be endothelial, inhibition of which partially prevented the increase in P-glycoprotein during reoxygenation. These data indicate that the production of nitric oxide by endothelial nitric oxide synthase during reoxygenation can influence P-glycoprotein expression in cells of the blood-rat brain barrier, highlighting another route by which nitric oxide may protect the brain.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Encéfalo/irrigação sanguínea , Células Endoteliais/metabolismo , Endotélio Vascular/citologia , Hipóxia/metabolismo , Óxido Nítrico/metabolismo , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/genética , Animais , Barreira Hematoencefálica/citologia , Barreira Hematoencefálica/metabolismo , Encéfalo/metabolismo , Linhagem Celular , Células Endoteliais/citologia , Doadores de Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo III/metabolismo , Oxigênio/metabolismo , Ratos , Espécies Reativas de Nitrogênio/metabolismo , Espécies Reativas de Oxigênio/metabolismo
20.
Gland Surg ; 10(1): 494-497, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33634007

RESUMO

Breast sensation has recently become an integral aspect of the reconstructive goal after mastectomy and is an important consideration for many patients. Neurotization techniques using primary coaptation, autograft, allograft, or nerve conduit have been used for autologous flaps, such as the deep inferior epigastric perforator (DIEP) flap. Outcomes have shown improved sensation and faster sensory recovery in the flap skin in immediate neurotized DIEP flap breast reconstructions compared to delayed reconstruction. Breast flap neurotization during reconstruction is a rapid and simple procedure with minimal morbidity. An improved understanding of breast anatomy and innovative modifications to breast reconstruction have made the restoration of breast sensation achievable, and promising results have been obtained with respect to sensory return and patient satisfaction.

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