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1.
J Appl Biomed ; 21(4): 218-227, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38112461

RESUMO

Spisulosine (1-deoxysphinganine) is a sphingoid amino alcohol isolated from the sea clams that showed potent antiproliferative activity against a broad spectrum of solid tumors but failed in clinical trials due to neurotoxicity. However, its structural similarity to other bioactive sphingoids, interesting mode of action, and appreciable potency against cancer cells make it a suitable lead for future anticancer drug development. The present study was conducted to elucidate mechanisms of the antiproliferative/cytotoxic effects of newly synthesized spisulosine analog homospisulosine (KP7). The evaluation was performed on cervical carcinoma cells, representing an in vitro model of one of the most common cancer types and a significant worldwide cause of women's cancer mortality. Treatment with homospisulosine (2.0 µM) for 24, 48, and 72 h significantly inhibited the growth of HeLa cells in vitro and induced apoptosis detectable by DNA fragmentation, externalization of phosphatidylserine, dissipation of mitochondrial membrane potential, activation of caspase-3 and cleavage of PARP. In addition, treating HeLa cells with spisulosine increased p27 and Bcl-2 on protein levels and phosphorylation of Bcl-2 on Ser70 residue. These results support the potential for spisulosine analogs represented here by homospisulosine for future therapeutic development.


Assuntos
Antineoplásicos , Carcinoma , Feminino , Humanos , Células HeLa , Regulação para Cima , Fosforilação , Apoptose , Antineoplásicos/farmacologia
2.
Emerg Infect Dis ; 28(5): 1060-1061, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35447060

RESUMO

Tick-borne encephalitis virus (TBEV) is transmitted mainly by tick bites, but humans can acquire infection through consuming unpasteurized milk from infected animals. Interhuman transmission of TBEV by breast milk has not been confirmed or ruled out. We report a case of probable transmission of TBEV from an unvaccinated mother to an infant through breast-feeding.


Assuntos
Vírus da Encefalite Transmitidos por Carrapatos , Encefalite Transmitida por Carrapatos , Picadas de Carrapatos , Animais , Feminino , Humanos , Leite Humano , Mães
3.
Bratisl Lek Listy ; 123(9): 601-617, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36039877

RESUMO

Non-pharmaceutical interventions (NPIs) were the only viable choice to mitigate or suppress transmission of COVID-19 in the absence of efficient and safe vaccines. In this study, we examined the association between the stringency of containment measures and cumulative incidence of the COVID-19 cases in the first wave of the pandemic across 28 European countries. Our results support the effectiveness of containment measures in the mitigation or suppression of COVID-19 epidemics. Early adoption of stringent containment measures prior to detection of the first confirmed case, together with ramping up containment stringency during the early days of epidemics, was associated with a lower disease occurrence. The delayed adoption of stringent containment measures did not fully compensate for the lack of early response. Containment measures continue to play a significant role in the control of COVID-19 in the post-vaccination period, when limited vaccination coverage, the emergence of vaccine resistance, and/or increased mobility enabled further disease transmission (Tab. 4, Fig. 22, Ref. 50). Keywords: non-pharmaceutical interventions, containment, COVID-19, mobility, social distancing, Containment and Health Index, epidemiology, public health measures, SARS-CoV-2.


Assuntos
COVID-19 , Controle de Doenças Transmissíveis , Quarentena , COVID-19/epidemiologia , COVID-19/prevenção & controle , Controle de Doenças Transmissíveis/métodos , Europa (Continente) , Humanos , Incidência , Pandemias/prevenção & controle , SARS-CoV-2
4.
Toxicol Appl Pharmacol ; 433: 115773, 2021 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-34688701

RESUMO

Carcinogenicity of hexavalent chromium [Cr (VI)] has been supported by a number of epidemiological and animal studies; however, its carcinogenic mode of action is still incompletely understood. To identify mechanisms involved in cancer development, we analyzed gene expression data from duodena of mice exposed to Cr(VI) in drinking water. This analysis included (i) identification of upstream regulatory molecules that are likely responsible for the observed gene expression changes, (ii) identification of annotated gene expression data from public repositories that correlate with gene expression changes in duodena of Cr(VI)-exposed mice, and (iii) identification of hallmark and oncogenic signature gene sets relevant to these data. We identified the inactivated CFTR gene among the top scoring upstream regulators, and found positive correlations between the expression data from duodena of Cr(VI)-exposed mice and other datasets in public repositories associated with the inactivation of the CFTR gene. In addition, we found enrichment of signatures for oncogenic signaling, sustained cell proliferation, impaired apoptosis and tissue remodeling. Results of our computational study support the tumor-suppressor role of the CFTR gene. Furthermore, our results support human relevance of the Cr(VI)-mediated carcinogenesis observed in the small intestines of exposed mice and suggest possible groups that may be more vulnerable to the adverse outcomes associated with the inactivation of CFTR by hexavalent chromium or other agents. Lastly, our findings predict, for the first time, the role of CFTR inactivation in chemical carcinogenesis and expand the range of plausible mechanisms that may be operative in Cr(VI)-mediated carcinogenesis of intestinal and possibly other tissues.


Assuntos
Transformação Celular Neoplásica/induzido quimicamente , Cromo/toxicidade , Regulador de Condutância Transmembrana em Fibrose Cística/genética , Neoplasias Duodenais/induzido quimicamente , Duodeno/efeitos dos fármacos , Inativação Gênica/efeitos dos fármacos , Proteínas Supressoras de Tumor/genética , Poluentes Químicos da Água/toxicidade , Administração Oral , Animais , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/metabolismo , Transformação Celular Neoplásica/patologia , Cromo/administração & dosagem , Regulador de Condutância Transmembrana em Fibrose Cística/metabolismo , Bases de Dados Genéticas , Água Potável , Neoplasias Duodenais/genética , Neoplasias Duodenais/metabolismo , Neoplasias Duodenais/patologia , Duodeno/metabolismo , Duodeno/patologia , Perfilação da Expressão Gênica , Camundongos , Medição de Risco , Biologia de Sistemas , Transcriptoma , Proteínas Supressoras de Tumor/metabolismo , Poluentes Químicos da Água/administração & dosagem
5.
Genes Chromosomes Cancer ; 59(10): 562-568, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32427409

RESUMO

Oncogenic gene fusions represent attractive targets for therapy of cancer. However, the frequency of actionable genomic rearrangements in colorectal cancer (CRC) is very low, and universal screening for these alterations seems to be impractical and costly. To address this problem, several large scale studies retrospectivelly showed that CRC with gene fusions are highly enriched in groups of tumors defined by MLH1 DNA mismatch repair protein deficiency (MLH1d), and hypermethylation of MLH1 promoter (MLH1ph), and/or the presence of microsatellite instability, and BRAF/KRAS wild-type status (BRAFwt/KRASwt). In this study, we used targeted next generation sequencing (NGS) to explore the occurence of potentially therapeutically targetable gene fusions in an unselected series of BRAFwt/KRASwt CRC cases that displayed MLH1d/MLH1ph. From the initially identified group of 173 MLH1d CRC cases, 141 cases (81.5%) displayed MLH1ph. BRAFwt/RASwt genotype was confirmed in 23 of 141 (~16%) of MLH1d/MLH1ph cases. Targeted NGS of these 23 cases identified oncogenic gene fusions in nine patients (39.1%; CI95: 20.5%-61.2%). Detected fusions involved NTRK (four cases), ALK (two cases), and BRAF genes (three cases). As a secondary outcome of NGS testing, we identified PIK3K-AKT-mTOR pathway alterations in two CRC cases, which displayed PIK3CA mutation. Altogether, 11 of 23 (~48%) MLH1d/MLH1ph/BRAFwt/RASwt tumors showed genetic alterations that could induce resistance to anti-EGFR therapy. Our study confirms that targeted NGS of MLH1d/MLH1ph and BRAFwt/RASwt CRCs could be a cost-effective strategy in detecting patients with potentially druggable oncogenic kinase fusions.


Assuntos
Adenocarcinoma/genética , Neoplasias Colorretais/genética , Testes Genéticos/métodos , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Proteína 1 Homóloga a MutL/deficiência , Proteínas de Fusão Oncogênica/genética , Adenocarcinoma/diagnóstico , Adulto , Idoso , Idoso de 80 Anos ou mais , Quinase do Linfoma Anaplásico/genética , Neoplasias Colorretais/diagnóstico , Metilação de DNA , Feminino , Testes Genéticos/normas , Sequenciamento de Nucleotídeos em Larga Escala/normas , Humanos , Masculino , Pessoa de Meia-Idade , Proteína 1 Homóloga a MutL/genética , Regiões Promotoras Genéticas , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Proto-Oncogênicas p21(ras)/genética , Receptores Proteína Tirosina Quinases/genética
6.
Toxicol Appl Pharmacol ; 380: 114706, 2019 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-31400414

RESUMO

High throughput screening (HTS) and functional genomics (toxicogenomics) have opened new avenues in toxicity testing. Their advantages include the potential for developing short-term in vivo bioassays and in vitro assays in order to keep pace with the growing backlog of chemicals that need to be evaluated for potential human health risk. In addition, these approaches have the potential to address some of the difficulties that arise with interpreting traditional rodent bioassays, such as the relevance of apical outcomes induced by chemical exposure in animals to humans. The wealth of information associated with the HTS and toxicogenomic data can inform human health risk assessment primarily through (i) insight into potential mechanism of action, (ii) prediction of adverse outcomes of chemical exposures, and (iii) dose-response assessment for derivation of toxicity values. In this article we outline current and expected future progress in these three directions and argue for increased role of HTS and toxicogenomic data in chemical risk assessment. We conclude that these approaches can help fulfill the NRC vision for toxicity testing in the 21st century and we discuss specific examples of chemicals whose health assessments can potentially benefit from available HTS or toxicogenomic data.


Assuntos
Ensaios de Triagem em Larga Escala , Medição de Risco/métodos , Toxicogenética/métodos , Animais , Carcinógenos/toxicidade , Humanos , Transcriptoma
7.
Cesk Patol ; 55(2): 115-119, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31181944

RESUMO

We present macroscopic and microscopic findings in a case of chronic dissecting aneurysm of ascending aorta and aortic arch associated with isolated tears of aortic wall without its rupture in a 71-year-old female presenting with minimal clinical symptomatology. Aneurysmal dilation of the aorta was caused not only by the bridging of the vascular wall based on the presence of an organizing intramural thrombus in the false lumen between the separated layers, but also by a wide flat defect in the aortic intima and media with the preservation of the aortic wall integrity due to fibrotical alteration of tunica adventicia. Histologic examination of the thoracic aorta detected cystic medial degeneration with mild atherosclerosis.


Assuntos
Dissecção Aórtica , Trombose , Idoso , Dissecção Aórtica/diagnóstico , Aorta/anormalidades , Feminino , Humanos , Trombose/diagnóstico
8.
Ann Diagn Pathol ; 33: 23-29, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29566943

RESUMO

Pulmonary small cell carcinoma (SCLC) is usually diagnosed in small biopsy or cytological specimens based on cytomorphology; however in ambiguous cases diagnosis requires additional support by immunohistochemistry. While TP53 and RB1 alterations with secondary overexpression of p16 are mainstay events in SCLC pathogenesis, diagnostic value of p16-positivity in the diagnosis of SCLC has not yet been fully investigated. We examined the expression of p16, CD56, synaptophysin (SYP), chromogranin A and thyroid transcription factor-1 (TTF1) in a series of pulmonary and extrapulmonary small cell carcinomas, pulmonary carcinoids and non-small cell lung carcinomas, and compared diagnostic performance of these markers in the diagnosis of SCLC. P16 was positive in 95 of 101 SCLCs, and displayed highest diagnostic sensitivity of ~94%. Composite biomarkers CD56+p16+TTF1 and CD56+p16+SYP were both able to detect correctly all SCLC cases. Importantly, three (~3%) SCLC cases completely negative for all conventional markers displayed diffuse positivity for p16. CD56 and p16 demonstrated highest concordance between paired small biopsy and cytology specimens. 50% of squamous cell carcinomas, ~41% of adenocarcinoma/NSCLC-favour adenocarcinoma cases, and ~93% of extrapulmonary small cell carcinomas also showed p16-positivity. Combination of CD56, p16 and TTF1 produced diagnostic classifier that outperformed best single marker CD56 in differential diagnosis between SCLC and NSCLC. In conclusion, in the appropriate morphological context p16 represents a useful supplementary marker for diagnosis of SCLC, even in cases where only cytological material is available.


Assuntos
Biomarcadores Tumorais/metabolismo , Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma de Células Pequenas/patologia , Genes p16/fisiologia , Neoplasias Pulmonares/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Biópsia , Tumor Carcinoide/diagnóstico , Tumor Carcinoide/patologia , Carcinoma de Células Pequenas/diagnóstico , Carcinoma de Células Escamosas/diagnóstico , Carcinoma de Células Escamosas/patologia , Diagnóstico Diferencial , Feminino , Humanos , Imuno-Histoquímica/métodos , Pulmão/patologia , Masculino , Pessoa de Meia-Idade
9.
BMC Cancer ; 16: 236, 2016 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-26988558

RESUMO

BACKGROUND: Epithelial-to-mesenchymal transition (EMT) has been associated with the acquisition of metastatic potential and the resistance of cancer cells to therapeutic treatments. MCF-7 breast cancer cells engineered to constitutively express the zinc-finger transcriptional repressor gene Snail (MCF-7-Snail cells) have been previously shown to display morphological and molecular changes characteristic of EMT. We report here the results of a comprehensive systems level molecular analysis of changes in global patterns of gene expression and levels of glutathione and reactive oxygen species (ROS) in MCF-7-Snail cells and the consequence of these changes on the sensitivity of cells to radiation treatment and therapeutic drugs. METHODS: Snail-induced changes in global patterns of gene expression were identified by microarray profiling using the Affymetrix platform (U133 Plus 2.0). The resulting data were processed and analyzed by a variety of system level analytical methods. Levels of ROS and glutathione (GSH) were determined by fluorescent and luminescence assays, and nuclear levels of NF-κB protein were determined by an ELISA based method. The sensitivity of cells to ionizing radiation and anticancer drugs was determined using a resazurin-based cell cytotoxicity assay. RESULTS: Constitutive ectopic expression of Snail in epithelial-like, luminal A-type MCF-7 cells induced significant changes in the expression of >7600 genes including gene and miRNA regulators of EMT. Mesenchymal-like MCF-7-Snail cells acquired molecular profiles characteristic of triple-negative, claudin-low breast cancer cells, and displayed increased sensitivity to radiation treatment, and increased, decreased or no change in sensitivity to a variety of anticancer drugs. Elevated ROS levels in MCF-7-Snail cells were unexpectedly not positively correlated with NF-κB activity. CONCLUSIONS: Ectopic expression of Snail in MCF-7 cells resulted in morphological and molecular changes previously associated with EMT. The results underscore the complexity and cell-type dependent nature of the EMT process and indicate that EMT is not necessarily predictive of decreased resistance to radiation and drug-based therapies.


Assuntos
Neoplasias da Mama/genética , Transição Epitelial-Mesenquimal/genética , Proteínas de Neoplasias/biossíntese , Fatores de Transcrição da Família Snail/biossíntese , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Neoplasias da Mama/radioterapia , Resistencia a Medicamentos Antineoplásicos/genética , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos da radiação , Humanos , Células MCF-7 , NF-kappa B/biossíntese , NF-kappa B/genética , Proteínas de Neoplasias/genética , Tolerância a Radiação/genética , Espécies Reativas de Oxigênio/metabolismo , Fatores de Transcrição da Família Snail/genética
10.
FASEB J ; 29(4): 1280-9, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25491311

RESUMO

A growing body of evidence suggests that the developmental process of epithelial-to-mesenchymal transition (EMT) is co-opted by cancer cells to metastasize to distant sites. This transition is associated with morphologic elongation and loss of cell-cell adhesions, though little is known about how it alters cell biophysical properties critical for migration. Here, we use multiple-particle tracking (MPT) microrheology and traction force cytometry to probe how genetic induction of EMT in epithelial MCF7 breast cancer cells changes their intracellular stiffness and extracellular force exertion, respectively, relative to an empty vector control. This analysis demonstrated that EMT alone was sufficient to produce dramatic cytoskeletal softening coupled with increases in cell-exerted traction forces. Microarray analysis revealed that these changes corresponded with down-regulation of genes associated with actin cross-linking and up-regulation of genes associated with actomyosin contraction. Finally, we show that this loss of structural integrity to expedite migration could inhibit mesenchymal cell proliferation in a secondary tumor as it accumulates solid stress. This work demonstrates that not only does EMT enable escape from the primary tumor through loss of cell adhesions but it also induces a concerted series of biophysical changes enabling enhanced migration of cancer cells after detachment from the primary tumor.


Assuntos
Citoesqueleto/genética , Transição Epitelial-Mesenquimal/genética , Transição Epitelial-Mesenquimal/fisiologia , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Actinas/metabolismo , Fenômenos Biofísicos , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Núcleo Celular/metabolismo , Núcleo Celular/patologia , Citoesqueleto/patologia , Feminino , Expressão Gênica , Humanos , Células MCF-7 , Análise de Sequência com Séries de Oligonucleotídeos , Fenótipo , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Fatores de Transcrição da Família Snail , Transformação Genética
11.
Am J Dermatopathol ; 38(10): 751-7, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26913849

RESUMO

An increased rate of second nonmelanoma skin cancers is found in immunocompromised patients. Epidemiological and molecular data implicate ultraviolet radiation as the major risk factor. In addition, there is increasing evidence supporting the role of human papillomavirus (HPV) in the pathogenesis of premalignant and malignant skin lesions in both immunocompetent and immunocompromised patients. In a retrospective cross-sectional study, the authors examined the expression of p16 by immunohistochemistry and the presence of mucosal (α-genus) and cutaneous/epidermodysplasia verruciformis (ß-genus) HPV DNA by polymerase chain reaction in 29 biopsy specimens of extragenital/extraungual Bowen disease (BD) from 24 Eastern European white immunocompromised patients. Furthermore, the author evaluated the association between the expression of p16 protein and the presence of HPV DNA. Among 25 specimens from 21 patients evaluable by polymerase chain reaction, HPV DNA was detected in 10 (40%) BD lesions from 9 patients. Beta-HPV predominated over alpha-HPV types. Among 29 immunohistochemically evaluable BD specimens, 22 lesions (∼76%) from 20 patients were scored as p16 positive. HPV DNA-positive and HPV DNA-negative lesions displayed the same proportion of p16 positivity (80%) and no correlation was found between the HPV DNA presence and the p16 expression status. Our pilot study demonstrated that ß-HPV infections predominate in BD cases diagnosed among immunocompromised patients, although high- and low-risk mucosal (alpha) HPV genotypes may be detected in a minority of cases. In contrast to anogenital HPV-associated lesions, positive p16 expression is not a reliable marker of high-risk α-HPV infection in BD cases, as it can be also detected in ß-HPV infected and HPV-negative cases.


Assuntos
Biomarcadores Tumorais/análise , Doença de Bowen/virologia , Inibidor p16 de Quinase Dependente de Ciclina/análise , Hospedeiro Imunocomprometido , Papillomaviridae/patogenicidade , Infecções por Papillomavirus/virologia , Lesões Pré-Cancerosas/virologia , Neoplasias Cutâneas/virologia , Idoso , Idoso de 80 Anos ou mais , Biópsia , Doença de Bowen/química , Doença de Bowen/imunologia , Transformação Celular Viral , Estudos Transversais , República Tcheca , DNA Viral/genética , Feminino , Testes de DNA para Papilomavírus Humano , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Papillomaviridae/genética , Papillomaviridae/imunologia , Infecções por Papillomavirus/imunologia , Projetos Piloto , Lesões Pré-Cancerosas/química , Lesões Pré-Cancerosas/imunologia , Valor Preditivo dos Testes , Estudos Retrospectivos , Fatores de Risco , Neoplasias Cutâneas/química , Neoplasias Cutâneas/imunologia
12.
Cesk Patol ; 52(3): 130-8, 2016.
Artigo em Tcheco | MEDLINE | ID: mdl-27526013

RESUMO

Human papillomavirus (HPV)-associated oropharyngeal squamous cell carcinoma (HPV-OSCC) represents a specific clinical and pathological entity among head and neck cancers with more favorable prognosis than corresponding HPV-negative oropharyngeal squamous cell carcinoma (SCC). HPV-OSCC most commonly displays non-keratinzing SCC histology, although number of cases presented variable morphology. Detection of transcriptionally active HPV in oropharyngeal SCCs is of critical prognostic importance, which even supersedes the importance of their formal pathological grading. This article summarizes the current state of knowledge of HPV-positive SCC of oropharynx and of other anatomical subsites of the head and neck and discusses the role of HPV detection in the diagnostics of metastatic SCC lesions of unknown origin.


Assuntos
Carcinoma de Células Escamosas/patologia , Neoplasias de Cabeça e Pescoço/patologia , Papillomaviridae , Infecções por Papillomavirus/patologia , Carcinoma de Células Escamosas/virologia , Neoplasias de Cabeça e Pescoço/virologia , Humanos , Imuno-Histoquímica , Hibridização In Situ , Infecções por Papillomavirus/virologia , Prognóstico
13.
J Proteome Res ; 13(7): 3444-54, 2014 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-24922590

RESUMO

Prostate cancer (PCa) is the second leading cause of cancer-related mortality in men. The prevalent diagnosis method is based on the serum prostate-specific antigen (PSA) screening test, which suffers from low specificity, overdiagnosis, and overtreatment. In this work, untargeted metabolomic profiling of age-matched serum samples from prostate cancer patients and healthy individuals was performed using ultraperformance liquid chromatography coupled to high-resolution tandem mass spectrometry (UPLC-MS/MS) and machine learning methods. A metabolite-based in vitro diagnostic multivariate index assay (IVDMIA) was developed to predict the presence of PCa in serum samples with high classification sensitivity, specificity, and accuracy. A panel of 40 metabolic spectral features was found to be differential with 92.1% sensitivity, 94.3% specificity, and 93.0% accuracy. The performance of the IVDMIA was higher than the prevalent PSA test. Within the discriminant panel, 31 metabolites were identified by MS and MS/MS, with 10 further confirmed chromatographically by standards. Numerous discriminant metabolites were mapped in the steroid hormone biosynthesis pathway. The identification of fatty acids, amino acids, lysophospholipids, and bile acids provided further insights into the metabolic alterations associated with the disease. With additional work, the results presented here show great potential toward implementation in clinical settings.


Assuntos
Biomarcadores Tumorais/sangue , Neoplasias da Próstata/diagnóstico , Idoso , Biomarcadores Tumorais/isolamento & purificação , Estudos de Casos e Controles , Cromatografia Líquida de Alta Pressão , Estudos de Viabilidade , Humanos , Masculino , Metabolômica , Pessoa de Meia-Idade , Neoplasias da Próstata/sangue , Espectrometria de Massas em Tandem
14.
Gynecol Oncol ; 134(1): 96-103, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24802724

RESUMO

OBJECTIVE: We recently determined that the ectopic over-expression of miR-429 and other members of the miR-200 family of microRNAs in ovarian cancer (OC) mesenchymal-like cell lines induces mesenchymal-to-epithelial transition (MET) with a concomitant increase in sensitivity to platinum drugs. We sought to determine if metastasizing OC cells isolated from an OC patient could also be induced by miR-429 to undergo MET and become sensitized to established first-line platinum-based therapies. METHODS: We established and characterized a new primary cell line (OCI-984) from free-floating OC cells isolated from the ascites fluid of an advanced stage OC patient. miR-429 was ectopically over-expressed in these cells. RESULTS: The over-expression of miR-429 in OCI-984 cells induced morphological, functional and molecular changes consistent with MET and a concomitant significant increase in the sensitivity of the converted cells to cisplatin. CONCLUSIONS: Our findings indicate that the miR-200 family of microRNAs, and miR-429 in particular, play a critical role in the functioning of OC metastasizing cells and that targeted delivery of miR-429, and perhaps other miR-200 family members, in combination with platinum-based chemotherapies may be an effective strategy in reducing OC metastasis and tumor recurrence.


Assuntos
Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Cisplatino/farmacologia , MicroRNAs/biossíntese , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/patologia , Idoso , Animais , Ensaios de Seleção de Medicamentos Antitumorais , Transição Epitelial-Mesenquimal/genética , Feminino , Humanos , Camundongos , Camundongos Nus , Neoplasias Ovarianas/tratamento farmacológico , Ensaios Antitumorais Modelo de Xenoenxerto
15.
Molecules ; 19(4): 3988-4005, 2014 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-24699144

RESUMO

Camalexin, the phytoalexin produced in the model plant Arabidopsis thaliana, possesses antiproliferative and cancer chemopreventive effects. We have demonstrated that the cytostatic/cytotoxic effects of camalexin on several prostate cancer (PCa) cells are due to oxidative stress. Lysosomes are vulnerable organelles to Reactive Oxygen Species (ROS)-induced injuries, with the potential to initiate and or facilitate apoptosis subsequent to release of proteases such as cathepsin D (CD) into the cytosol. We therefore hypothesized that camalexin reduces cell viability in PCa cells via alterations in expression and activity of CD. Cell viability was evaluated by MTS cell proliferation assay in LNCaP and ARCaP Epithelial (E) cells, and their respective aggressive sublines C4-2 and ARCaP Mesenchymal (M) cells, whereby the more aggressive PCa cells (C4-2 and ARCaPM) displayed greater sensitivity to camalexin treatments than the lesser aggressive cells (LNCaP and ARCaPE). Immunocytochemical analysis revealed CD relocalization from the lysosome to the cytosol subsequent to camalexin treatments, which was associated with increased protein expression of mature CD; p53, a transcriptional activator of CD; BAX, a downstream effector of CD, and cleaved PARP, a hallmark for apoptosis. Therefore, camalexin reduces cell viability via CD and may present as a novel therapeutic agent for treatment of metastatic prostate cancer cells.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Arabidopsis/química , Catepsina D/genética , Regulação da Expressão Gênica/efeitos dos fármacos , Indóis/farmacologia , Tiazóis/farmacologia , Antineoplásicos Fitogênicos/isolamento & purificação , Apoptose/efeitos dos fármacos , Catepsina D/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Ativação Enzimática/efeitos dos fármacos , Humanos , Indóis/isolamento & purificação , Lisossomos/efeitos dos fármacos , Lisossomos/metabolismo , Masculino , Especificidade de Órgãos , Estresse Oxidativo , Extratos Vegetais/química , Poli(ADP-Ribose) Polimerases/genética , Poli(ADP-Ribose) Polimerases/metabolismo , Próstata/efeitos dos fármacos , Próstata/enzimologia , Próstata/patologia , Transdução de Sinais , Tiazóis/isolamento & purificação , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Proteína X Associada a bcl-2/genética , Proteína X Associada a bcl-2/metabolismo
16.
Carbohydr Res ; 541: 109158, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38796901

RESUMO

Straightforward access to enantiomerically pure 3,4-diamino-3,4-dideoxyphytosphingosines, as novel analogues of natural d-ribo-phytosphingosine was accomplished, starting from two available chirons: dimethyl l-tartrate and d-isoascorbic acid. A sequential Overman rearrangement followed by late-stage introduction of the alkyl side chain moiety via olefin cross-metathesis is the cornerstone of this approach. The preliminary evaluation study of the synthesised sphingomimetics, based on their ability to inhibit a proliferation of human cancer cells, showed promising cytotoxicity against Jurkat and HeLa cells for (2R,3R,4S)-2,3,4-triaminooctadecan-1-ol trihydrochloride.


Assuntos
Proliferação de Células , Esfingosina , Esfingosina/análogos & derivados , Esfingosina/química , Esfingosina/farmacologia , Esfingosina/síntese química , Humanos , Células HeLa , Proliferação de Células/efeitos dos fármacos , Células Jurkat , Antineoplásicos/farmacologia , Antineoplásicos/química , Antineoplásicos/síntese química , Estereoisomerismo
17.
Anticancer Drugs ; 24(5): 504-18, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23511429

RESUMO

Preliminary studies have suggested that the reactive oxygen species (ROS) scavenger N-acetyl-L-cysteine (NAC) may be effective in inhibiting the growth of pancreatic cancer cells. In-depth cellular and molecular analyses were carried out to determine NAC's mode of action in inhibiting the growth of a well-characterized pancreatic cancer cell line (AsPC-1). Standardized assays were used to monitor cellular growth, apoptosis, levels of ROS, cellular senescence, migration, and invasiveness. Cell stiffness was measured using atomic force microscopy. Gene expression was monitored by quantitative PCR. NAC significantly inhibits the growth and metastatic potential of AsPC-1 cells by inducing cell-cycle arrest in G1 and subsequent cellular senescence and decreased invasiveness. These anticancer properties are associated with an unexpected increase in the intracellular concentrations of ROS. NAC does not decrease the susceptibility of AsPC-1 cells to the anticancer drugs gemcitabine, mitomycin C, and doxorubicin. NAC-induced changes in gene expression are consistent with the onset of mesenchymal-to-epithelial transition. In conclusion, our findings indicate that NAC induces an integrated series of responses in AsPC-1 cells that make it a highly promising candidate for development as a pancreatic cancer therapeutic.


Assuntos
Acetilcisteína/farmacologia , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/patologia , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Senescência Celular/efeitos dos fármacos , Desoxicitidina/análogos & derivados , Desoxicitidina/farmacologia , Relação Dose-Resposta a Droga , Doxorrubicina/farmacologia , Pontos de Checagem da Fase G1 do Ciclo Celular/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Genes myc , Humanos , Mitomicina/farmacologia , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Gencitabina
18.
Bioorg Med Chem ; 21(21): 6623-33, 2013 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-24012378

RESUMO

An effective synthesis of analogs of the indole phytoalexin cyclobrassinin with NR1R2 group instead of SCH3 was developed starting from indole-3-carboxaldehyde. The target compounds were prepared by spirocyclization of 1-Boc-thioureas with the formation of isolable spiroindoline intermediates, followed by the trifluoroacetic acid-induced cascade reaction consisting of methanol elimination, deprotection and rearrangement of the iminium ion. The structures of novel products were elucided by the (1)H and (13)C NMR spectroscopy, including HMBC, HSQC, COSY, NOESY and DEPT measurements. Several newly synthesized compounds demonstrated significant antiproliferative/cytotoxic activity against human leukemia and solid tumor cell lines, as well as remarkable selectivity of these effects against cancer cells relative to the non-malignant HUVEC cells.


Assuntos
Antineoplásicos/síntese química , Indóis/química , Sesquiterpenos/química , Tiocarbamatos/química , Antineoplásicos/química , Antineoplásicos/toxicidade , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Células HeLa , Células Endoteliais da Veia Umbilical Humana , Humanos , Indóis/síntese química , Indóis/toxicidade , Células Jurkat , Células MCF-7 , Espectroscopia de Ressonância Magnética , Estereoisomerismo , Tiocarbamatos/síntese química , Tiocarbamatos/toxicidade , Fitoalexinas
19.
Adv Med Sci ; 68(2): 417-425, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37866204

RESUMO

Programmed cell death plays a crucial role in maintaining the homeostasis and integrity of multicellular organisms, and its dysregulation contributes to the pathogenesis of many diseases. Programmed cell death is regulated by a range of macromolecules and low-molecular messengers, including ceramides. Endogenous ceramides have different functions, that are influenced by their localization and the presence of their target molecules. This article provides an overview of the current understanding of ceramides and their impact on various types of programmed cell death, including apoptosis, anoikis, macroautophagy and mitophagy, and necroptosis. Moreover, it highlights the emergence of dihydroceramides as a new class of bioactive sphingolipids and their downstream targets as well as their future roles in cancer cell growth, drug resistance and tumor metastasis.


Assuntos
Apoptose , Ceramidas , Ceramidas/metabolismo , Esfingolipídeos/metabolismo , Homeostase
20.
iScience ; 26(4): 106393, 2023 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-37034996

RESUMO

Stiffness has been observed to decrease for many cancer cell types as their metastatic potential increases. Although cell mechanics and metastatic potential are related, the underlying molecular factors associated with these phenotypes remain unknown. Therefore, we have developed a workflow to measure the mechanical properties and gene expression of single cells that is used to generate large linked-datasets. The process combines atomic force microscopy to measure the mechanics of individual cells with multiplexed RT-qPCR gene expression analysis on the same single cells. Surprisingly, the genes that most strongly correlated with mechanical properties were not cytoskeletal, but rather were markers of extracellular matrix remodeling, epithelial-to-mesenchymal transition, cell adhesion, and cancer stemness. In addition, dimensionality reduction analysis showed that cell clustering was improved by combining mechanical and gene expression data types. The single cell genomechanics method demonstrates how single cell studies can identify molecular drivers that could affect the biophysical processes underpinning metastasis.

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