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1.
Transl Oncol ; 14(12): 101229, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34592589

RESUMO

Tumour metastasis accounts for over 90% of cancer related deaths. The platelet is a key blood component, which facilitates efficient metastasis. This study aimed to understand the molecular mechanisms involved in tumour-platelet cell interactions. The interaction between cancer cells and platelets was examined in 15 epithelial cell lines, representing 7 cancer types. Gene expression analysis of EMT-associated and cancer stemness genes was performed by RT-PCR. Whole transcriptome analysis (WTA) was performed using Affymetrix 2.0ST arrays on a platelet co-cultured ovarian model. Platelet adhesion and activation occurred across all tumour types. WTA identified increases in cellular movement, migration, invasion, adhesion, development, differentiation and inflammation genes and decreases in processes associated with cell death and survival following platelet interaction. Increased invasive capacity was also observed in a subset of cell lines. A cross-comparison with a platelet co-cultured mouse model identified 5 common altered genes; PAI-1, PLEK2, CD73, TNC, and SDPR. Platelet cancer cell interactions are a key factor in driving the pro-metastatic phenotype and appear to be mediated by 5 key genes which have established roles in metastasis. Targeting these metastasis mediators could improve cancer patient outcomes.

2.
BMC Cancer ; 15: 627, 2015 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-26353776

RESUMO

BACKGROUND: Platelet-cancer cell interactions play a key role in successful haematogenous metastasis. Disseminated malignancy is the leading cause of death among ovarian cancer patients. It is unknown why different ovarian cancers have different metastatic phenotypes. To investigate if platelet-cancer cell interactions play a role, we characterized the response of ovarian cancer cell lines to platelets both functionally and at a molecular level. METHODS: Cell lines 59 M and SK-OV-3 were used as in vitro model systems of metastatic ovarian cancer. Platelet cloaking of each cell line was quantified by flow cytometry. Matrigel invasion chamber assays were used to assess the invasive capacity of the cell lines. The induction of an EMT was assessed by morphology analysis and by gene expression analysis of a panel of 11 EMT markers using TaqMan RT-PCR. RESULTS: SK-OV-3 cells adhered to and activated more platelets than 59 M cells (p = 0.0333). Platelets significantly promoted the ability of only SK-OV-3 cells to invade (p ≤ 0.0001). Morphology and transcritpome analysis indicated that platelets induce an epithelial-to-mesenchymal transition phenotype in both cells lines, with a more exaggerated response in SK-OV-3 cells. Next, we investigated if antiplatelet agents could abrogate the platelet-induced aggressive phenotype in SK-OV-3 cells. Both aspirin (p ≤ 0.05) and 2-methylthioadenosine 5'-monophosphate triethylammonium salt hydrate (P2Y12 inhibitor; p ≤ 0.01) significantly decreased their invasion capacity, and effectively reverted invasion to levels comparable to SK-OV-3 cells alone. CONCLUSION: While there is increasing evidence for the cancer-protective effect of aspirin, this study suggests P2Y12 inhibition may also play a role. Understanding these complex interactions between platelets and cancer cells could ultimately allow the establishment of therapies tailored to inhibiting metastasis, thus significantly reducing cancer morbidity.


Assuntos
Aspirina/farmacologia , Plaquetas/fisiologia , Invasividade Neoplásica , Neoplasias Ovarianas/patologia , Inibidores da Agregação Plaquetária/farmacologia , Antagonistas do Receptor Purinérgico P2Y/farmacologia , Receptores Purinérgicos P2Y12/efeitos dos fármacos , Monofosfato de Adenosina/análogos & derivados , Monofosfato de Adenosina/farmacologia , Linhagem Celular Tumoral , Feminino , Citometria de Fluxo , Humanos , Metástase Neoplásica , Reação em Cadeia da Polimerase em Tempo Real
3.
Infect Immun ; 82(1): 298-305, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24166954

RESUMO

Extraintestinal Escherichia coli (ExPEC) organisms are the leading cause of Gram-negative bacterial bloodstream infections. These bacteria adapt to survival in the bloodstream through expression of factors involved in scavenging of nutrients and resisting the killing activity of serum. In this study, the transcriptional response of a prototypic ExPEC strain (CFT073) to human serum was investigated. Resistance of CFT073 to the bactericidal properties of serum involved increased expression of envelope stress regulators, including CpxR, σE, and RcsB. Many of the upregulated genes induced by active serum were regulated by the Rcs two-component system. This system is triggered by envelope stress such as changes to cell wall integrity. RcsB-mediated serum resistance was conferred through induction of the exopolysaccharide colanic acid. Production of this exopolysaccharide may be protective while cell wall damage caused by serum components is repaired.


Assuntos
Atividade Bactericida do Sangue , Proteínas de Escherichia coli/metabolismo , Escherichia coli/metabolismo , Polissacarídeos/metabolismo , Atividade Bactericida do Sangue/imunologia , Proteínas do Sistema Complemento/metabolismo , Escherichia coli/genética , Regulação Bacteriana da Expressão Gênica , Humanos , Análise em Microsséries , Estresse Fisiológico/fisiologia
4.
Cancer Med ; 2(4): 564-70, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24156029

RESUMO

Platelet hyperreactivity is associated with an increased risk of thrombosis. Cancer patients are at an increased risk of thrombosis, a risk that increases with disease progression. While cancer patients show evidence of platelet activation in vivo, few studies have extensively assessed whether these patients display platelet hyperreactivity. We hypothesized that patients with metastatic cancer would display platelet hyperreactivity, reflecting their associated high risk of thrombosis. In a cohort of patients with metastatic cancer (n = 13), we assessed platelet function using well-established assays of platelet reactivity (agonist-induced platelet aggregation, spontaneous platelet aggregation, and agonist-induced P-selectin expression). In comparison with healthy controls (n = 10), patients with metastatic cancer displayed global platelet hyperreactivity. Agonist-induced platelet aggregation responses to ADP (adenosine diphosphate), epinephrine, collagen, arachidonic acid, and PAR-1 (protease-activated receptor-1) activating peptide, as well as spontaneous platelet aggregation, were significantly increased in patients with metastatic cancer. Furthermore, agonist-induced platelet P-selectin expression was also significantly increased within the patient cohort. We demonstrate that patients with metastatic cancer are characterized by global platelet hyperreactivity, a factor that may contribute to their increased risk of thrombosis.


Assuntos
Neoplasias/sangue , Neoplasias/patologia , Ativação Plaquetária , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , Estadiamento de Neoplasias , Neoplasias/complicações , Agregação Plaquetária , Contagem de Plaquetas , Trombocitose/etiologia
5.
Int J Antimicrob Agents ; 35(6): 593-8, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20356716

RESUMO

A DNA microarray was developed to detect plasmid-mediated antimicrobial resistance (AR) and virulence factor (VF) genes in clinical isolates of Enterobacteriaceae and non-Enterobacteriaceae. The array was validated with the following bacterial species: Escherichiacoli (n=17); Klebsiellapneumoniae (n=3); Enterobacter spp. (n=6); Acinetobacter genospecies 3 (n=1); Acinetobacterbaumannii (n=1); Pseudomonasaeruginosa (n=2); and Stenotrophomonasmaltophilia (n=2). The AR gene profiles of these isolates were identified by polymerase chain reaction (PCR). The DNA microarray consisted of 155 and 133 AR and VF gene probes, respectively. Results were compared with the commercially available Identibac AMR-ve Array Tube. Hybridisation results indicated that there was excellent correlation between PCR and array results for AR and VF genes. Genes conferring resistance to each antibiotic class were identified by the DNA array. Unusual resistance genes were also identified, such as bla(SHV-5) in a bla(OXA-23)-positive carbapenem-resistant A. baumannii. The phylogenetic group of each E. coli isolate was verified by the array. These data demonstrate that it is possible to screen simultaneously for all important classes of mobile AR and VF genes in Enterobacteriaceae and non-Enterobacteriaceae whilst also assigning a correct phylogenetic group to E. coli isolates. Therefore, it is feasible to test clinical Gram-negative bacteria for all known AR genes and to provide important information regarding pathogenicity simultaneously.


Assuntos
Proteínas de Bactérias/genética , Técnicas Bacteriológicas/métodos , Farmacorresistência Bacteriana , Bactérias Gram-Negativas/genética , Infecções por Bactérias Gram-Negativas/microbiologia , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Fatores de Virulência/genética , Genes Bacterianos , Bactérias Gram-Negativas/isolamento & purificação , Humanos , Sensibilidade e Especificidade
6.
J Clin Microbiol ; 48(4): 1099-104, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20107091

RESUMO

Escherichia coli is a major cause of bloodstream infections and death due to sepsis. It is the most frequent Gram-negative bacterial pathogen recovered from cultures of blood from both community-acquired and nosocomial cases. We set out to determine the relationships between E. coli virulence factors (VFs), phylogenetic groups, and antibiotic resistance and whether bacteremia cases had a community, health care-associated. or nosocomial origin. Isolates from consecutive episodes of E. coli bacteremia in 303 patients presenting to a university hospital were screened for their VFs, phylogenetic group, and antibiotic resistance. The majority of VFs present in the collection were equally distributed between antibiotic-susceptible and multiple-drug-resistant (MDR) isolates, but the overall VF score was higher for isolates of community and health care-associated origin than those of nosocomial origin (P = 0.0002 and P = 0.0172, respectively); the papA, papG allele II, hlyA, and hek VFs were more prevalent in this cohort. Most isolates belonged to phylogenetic group B2, which harbored a greater proportion of antibiotic-susceptible isolates than MDR isolates (P = 0.04). The community, health care-associated, or nosocomial origin of E. coli bacteremia determines the virulence capacity of an isolate better than the phylogenetic group does. This study provides new insights into the relationships between the pathogenesis and epidemiology of E. coli bacteremia.


Assuntos
Bacteriemia/microbiologia , Infecções Comunitárias Adquiridas/microbiologia , Infecção Hospitalar/microbiologia , Farmacorresistência Bacteriana Múltipla , Infecções por Escherichia coli/microbiologia , Escherichia coli/isolamento & purificação , Fatores de Virulência/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Técnicas de Tipagem Bacteriana , Análise por Conglomerados , Impressões Digitais de DNA , Escherichia coli/efeitos dos fármacos , Escherichia coli/patogenicidade , Proteínas de Escherichia coli/genética , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Epidemiologia Molecular , Filogenia , Adulto Jovem
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