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1.
Adv Healthc Mater ; 12(29): e2301186, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37672681

RESUMO

Although human pluripotent stem cells (hPSCs)-derived cardiomyocytes (hPSC-CMs) can remuscularize infarcted hearts and restore post-infarct cardiac function, post-transplant rejection resulting from human leukocyte antigen (HLA) mismatching is an enormous obstacle. It is crucial to identify hypoimmunogenic hPSCs for allogeneic cell therapy. This study is conducted to demonstrate the immune privilege of HLA-Ehigh /HLA-Ghigh /HLA-IIlow human induced pluripotent stem cell (hiPSC)-derived cardiomyocytes (hiPSC-CMs). Ischemia-reperfusion surgery is done to create transmural myocardial infarction in rats. At post-infarct 4 days, hPSC-CMs (1.0×107 cells per kg), including human embryonic stem cell-derived cardiomyocytes (hESC-CMs), HLA-Elow/HLA-Glow/HLA-IIhigh hiPSC-CMs, and HLA-Ehigh /HLA-Ghigh /HLA-IIlow hiPSC-CMs, are injected into the infarcted myocardium. Under the treatment of very low dose cyclosporine A (CsA), only HLA-Ehigh /HLA-Ghigh /HLA-IIlow hiPSC-CMs survive in vivo and improved post-infarct cardiac function with infarct size reduction. HLA-Ehigh /HLA-Ghigh /HLA-IIlow hiPSC-CMs activate the SHP-1 signaling pathway of natural killer (NK) cells and cytotoxic T cells to evade attack by NK cells and cytotoxic T cells. Herein, it is demonstrated that using a clinically relevant CsA dose, HLA-Ehigh /HLA-Ghigh /HLA-IIlow hiPSC-CMs repair the infarcted myocardium and restore the post-infarct heart function. HLA-Ehigh /HLA-Ghigh /HLA-IIlow hiPSCs are less immunogenic and may serve as platforms for regeneration medicine.


Assuntos
Células-Tronco Pluripotentes Induzidas , Infarto do Miocárdio , Humanos , Ratos , Animais , Miócitos Cardíacos/metabolismo , Células-Tronco Pluripotentes Induzidas/metabolismo , Antígenos HLA-G/metabolismo , Infarto do Miocárdio/terapia , Regeneração , Diferenciação Celular , Antígenos HLA-E
2.
Free Radic Biol Med ; 208: 103-111, 2023 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-37549754

RESUMO

Doxorubicin (Dox) is a potent anticancer agent, but its associated organ toxicity, including nephrotoxicity, restricts clinical applications. Dapagliflozin (DAPA), a sodium-glucose cotransporter-2 inhibitor, has been shown to slow the progression of kidney disease in patients with and without diabetes. However, the effect of DAPA to counteract Dox-induced nephrotoxicity remains uncertain. Therefore, in this study, we aimed to elucidate the effects of DAPA in mitigating Dox-induced nephrotoxicity. We analyzed the Taiwan National Health Insurance Database to evaluate the incidence of renal failure among breast cancer patients receiving Dox treatment compared to those without. After adjusting for age and comorbidities, we found that the risk of renal failure was significantly higher in Dox-treated patients (incidence rate ratio, 2.45; confidence interval, 1.41-4.26; p = 0.0014). In a parallel study, we orally administered DAPA to Sprague-Dawley rats for 6 weeks, followed by Dox for 4 weeks. DAPA ameliorated Dox-induced glomerular atrophy, renal fibrosis, and dysfunction. Furthermore, DAPA effectively suppressed Dox-induced apoptosis and reactive oxygen species production. On a cellular level, DAPA in HK-2 cells mitigated Dox-mediated suppression of the endothelial NOS pathway and reduced Dox-induced activities of reactive oxygen species and apoptosis-associated proteins. DAPA improved Dox-induced apoptosis and renal dysfunction, suggesting its potential utility in preventing nephrotoxicity in patients with cancer undergoing Dox treatment.


Assuntos
Nefropatias , Insuficiência Renal , Inibidores do Transportador 2 de Sódio-Glicose , Humanos , Ratos , Animais , Óxido Nítrico/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Inibidores do Transportador 2 de Sódio-Glicose/efeitos adversos , Ratos Sprague-Dawley , Doxorrubicina/efeitos adversos , Nefropatias/induzido quimicamente , Insuficiência Renal/induzido quimicamente , Apoptose
3.
Int J Mol Sci ; 23(21)2022 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-36362062

RESUMO

Programmed death-ligand 1 (PD-L1) is an immune checkpoint molecule that can regulate immune responses in the tumor microenvironment (TME); however, the clinical applications of PD-L1 in early-stage colorectal cancer (CRC) remain unclear. In this study, we aimed to investigate the relationship between PD-L1 expression and survival outcome and explore its relevant immune responses in CRC. PD-L1 expression was evaluated by immunohistochemical staining to determine the tumor proportion score and combined positive score (CPS) in a Taiwanese CRC cohort. The oncomine immune response research assay was conducted for immune gene expression analyses. CRC datasets from the TCGA database were reappraised for PD-L1-associated gene enrichment analyses using GSEA. The high expression of PD-L1 (CPS ≥ 5) was associated with longer recurrence-free survival (p = 0.031) and was an independent prognostic factor as revealed by multivariate analysis. High PD-L1 expression was related to six immune-related gene signatures, and CXCL9 is the most significant overexpressed gene in differential analyses. High CXCL9 expression correlated with increased infiltration levels of immune cells in the TME, including CD8+ T lymphocytes and M1 macrophages. These findings suggest that high PD-L1 expression is a prognostic factor of early-stage CRC, and CXCL9 may play a key role in regulating PD-L1 expression.


Assuntos
Antígeno B7-H1 , Neoplasias Colorretais , Humanos , Antígeno B7-H1/metabolismo , Linfócitos do Interstício Tumoral , Microambiente Tumoral/genética , Neoplasias Colorretais/patologia
4.
Am J Cancer Res ; 12(5): 2189-2202, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35693078

RESUMO

Both efficacy and tolerability are critical issues in choosing neoadjuvant chemotherapy in patients with unresectable locally advanced pancreatic cancer (LAPC). The optimal regimen and the impact of conversion surgery on patient survival remains insufficiently reported in Asain population. Therefore, we conducted a retrospective study aiming to evaluate the resection rate after different induction chemotherapy regimen and its impact toward survival. All patients with pancreatic cancer treated in our institute from 2013 to 2020, a total of 730 patients, were reviewed and 131 patients with LAPC were identified. For cohort homogeneity, 14 patients receiving induction concurrent chemoradiotherapy initially were excluded and 117 patients receiving induction chemotherapy were included in the study. Most patients (90 of 117, 77%) received triplet induction chemotherapy, including the combination of S1, leucovorin, oxaliplatin and gemcitabine (SLOG) in 48, modified FOLFIRINOX in 21 and the combination of gemcitabine, oxaliplatin, fluorouracil and leucovorin (GOFL) in 21. The tumor response rate (19%-33%), the surgical exploration rate (38%-52%) and the mOS (15.4-23.0 months) were not significantly different among the three triplets. Both GOFL and SLOG regimen had comparable efficacy and less neutropenia as compared to mFOLFIRINOX. Conversion surgery was performed in 34 of 117 (29%) patients after induction chemotherapy. The median overall survival (mOS) in patients with and without conversion surgery were 29.1 and 14.1 months, respectively (P<0.0001). Radiological response alone was not a reliable indicator of successful conversion surgery. Patients who underwent conversion surgery had significantly better survival and thus highlighted the importance of surgical exploration in all patients who did not have progressive disease after induction chemotherapy.

5.
BMC Ophthalmol ; 22(1): 43, 2022 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-35093058

RESUMO

BACKGROUND: Amyloidosis is a rare, progressive and variable group of diseases characterized by extracellular deposits of amyloid protein in different tissues and organs. It is a protein-misfolding disease in which small proteins of about 10 to 15 kDa acquire an alternative and relatively misfolded state at minimum energy and subsequently aggregate into oligomers and polymers. It mimics other eyelid diseases, such as involutional ptosis, eyelid granulomatous or cancerous lesions. Misdiagnosis of eyelid amyloidosis is usual when the lesion grows slowly and insidiously. Definite diagnosis depends on clinical suspicion and tissue-proven biopsy. CASE PRESENTATION: A 50-year-old female had painless progressive ptosis in both eyes for 6 months. She presented with limited upward gaze due to swelling of the upper eyelids OU. She complained of mild foreign body sensation. Upon examination, we observed an infiltrated irregular yellowish mass on the surface of her upper palpebral conjunctiva in both eyes. The mass was non-movable without tenderness. We performed excisional biopsy for the masses and subsequent histopathology of the biopsy specimens revealed amyloidosis. Systemic workup showed no other lesions. Unfortunately, her ptosis and upward gaze restriction was not improved after the operation. However, the masses did not enlarge in the following 3 months. CONCLUSIONS: The varied presentations of ocular adnexal and orbital amyloidosis often lead to a significant delay between first symptoms and diagnosis. Immediate confirmatory biopsy and subsequent systemic workup should be performed whenever amyloidosis is highly suspected.


Assuntos
Amiloidose , Blefaroptose , Doenças da Túnica Conjuntiva , Doenças Palpebrais , Amiloidose de Cadeia Leve de Imunoglobulina , Amiloidose/complicações , Amiloidose/diagnóstico , Blefaroptose/diagnóstico , Blefaroptose/etiologia , Doenças Palpebrais/diagnóstico , Feminino , Humanos , Pessoa de Meia-Idade
7.
Acta Cardiol Sin ; 37(6): 591-599, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34812232

RESUMO

BACKGROUND: Serving as an inflammatory biomarker in patients under regular hemodialysis (HD), the arterial tissue expression of vascular cell adhesion molecule 1 (VCAM-1) in patients with different renal function has rarely been investigated and remains unclear. METHODS: Fifty-one consecutive patients with peripheral arterial disease (PAD) who underwent percutaneous transluminal angioplasty were recruited and divided into a normal renal function group, chronic kidney disease (CKD) group, and HD group. Background disease, clinical and angiographic severity, and serum level of VCAM-1 in the three groups were analyzed. The tissue expression of VCAM-1 was quantitatively demonstrated by immunohistochemical (IHC) staining and protein extraction from cell membranes in another amputated cohort. RESULTS: In PAD patients, the serum level of VCAM-1 was significantly elevated in the HD group compared with the other two groups (1990.2 ± 607.1 ng/ml vs. 1547.9 ± 511.2 ng/ml vs. 1161.0 ± 435.8 ng/ml, p < 0.001). Serum VCAM-1 was a prognostic factor of major adverse cardiac or limb events (odds ratio: 1.002, 95% confidence interval: 1.001-1.003, p = 0.003). The expression of VCAM-1 was higher in the PAD amputated arterial tissue of CKD and HD patients as demonstrated by quantitative analysis of IHC staining and quantitative membrane protein extraction. CONCLUSIONS: VCAM-1 is a cardiovascular prognostic biomarker. Both serum level and the tissue expression of VCAM-1 were significantly higher in PAD patients with advanced kidney disease.

8.
Am J Surg Pathol ; 45(11): 1561-1572, 2021 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-34010154

RESUMO

Adult-onset immunodeficiency syndrome (AOIS) caused by anti-interferon-γ autoantibodies is an emerging disease. Affected patients present typically with systemic lymphadenopathy, fatigue, and fever. We studied 36 biopsy specimens, 31 lymph nodes, and 5 extranodal sites, of AOIS confirmed by serum autoantibody or QuantiFERON-TB Gold In-Tube assay. We describe the morphologic features and the results of ancillary studies, including special stains, immunohistochemistry, and molecular testing. The overall median age of these patients was 60.5 years (range, 41 to 83 y) with a male-to-female ratio of 20:16. All biopsy specimens showed nontuberculous mycobacterial infection, and most cases showed the following histologic features: capsular thickening with intranodal sclerosing fibrosis, irregularly distributed ill-formed granulomas or histiocytic aggregates with neutrophilic infiltration, interfollicular expansion by a polymorphic infiltrate with some Hodgkin-like cells that commonly effaces most of the nodal architecture and proliferation of high endothelial venules. In situ hybridization analysis for Epstein-Barr virus-encoded RNA showed scattered (<1%) to relatively more common (4% to 5%) positive cells in 29 of 30 (97%) tested specimens, reflecting immune dysregulation due to an interferon-γ defect. In the 31 lymph node specimens, 23 (74%) cases showed increased immunoglobulin G4-positive plasma cells (4 to 145/HPF; mean, 49.7/HPF) with focal areas of sclerosis reminiscent of immunoglobulin G4-related lymphadenopathy, 4 (13%) cases resembled, in part, nodular sclerosis Hodgkin lymphoma, and 9 (29%) cases mimicked T-cell lymphoma. Among 33 patients with available clinical follow-up, 20 (61%) showed persistent or refractory disease despite antimycobacterial therapy, and 1 patient died of the disease. We conclude that the presence of ill-defined granulomas, clusters of neutrophils adjacent to the histiocytic aggregates, and some Epstein-Barr virus-positive cells are features highly suggestive of AOIS. A high index of clinical suspicion and awareness of the morphologic features and differential diagnosis of AOIS are helpful for establishing the diagnosis.


Assuntos
Autoanticorpos/sangue , Síndromes de Imunodeficiência/imunologia , Interferon gama/imunologia , Linfonodos/imunologia , Linfadenopatia/imunologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/sangue , Biópsia , Diagnóstico Diferencial , Feminino , Herpesvirus Humano 4/isolamento & purificação , Histiócitos/imunologia , Histiócitos/patologia , Humanos , Síndromes de Imunodeficiência/microbiologia , Síndromes de Imunodeficiência/patologia , Síndromes de Imunodeficiência/virologia , Linfonodos/microbiologia , Linfonodos/patologia , Linfonodos/virologia , Linfadenopatia/microbiologia , Linfadenopatia/patologia , Linfadenopatia/virologia , Masculino , Pessoa de Meia-Idade , Neutrófilos/imunologia , Neutrófilos/patologia , Micobactérias não Tuberculosas/isolamento & purificação , Valor Preditivo dos Testes , Prognóstico
9.
Histopathology ; 74(6): 933-943, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30604891

RESUMO

AIMS: Spindle cell/sclerosing rhabdomyosarcomas (SC/SRMS) feature spindled and/or rounded rhabdomyosarcomatous cells within variably hyalinised stroma. Only 30-67% of SC/SRMSs harbour neomorphic MYOD1 p.L122R mutations, indicating heterogeneity in this RMS type. We compared MYOD1-mutant and non-mutant cases to characterise the histological and genetic spectrum of mutated SC/SRMS. METHODS AND RESULTS: Seventeen RMSs with spindled, sclerosing or hybrid histology were sequenced to identify MYOD1 and PIK3CA mutations and reappraised to assess histological features and myogenic immunophenotypes. Twelve SC/SRMSs harboured MYOD1 mutations, including homozygous p.L122R (n = 8), heterozygous p.L122R (n = 3) and heterozygous p.E118K (n = 1). MYOD1-mutant tumours affected nine females and three males aged 8-64 years (median = 22.5), had a median size of 4.2 cm (range = 2-22) and involved the head and neck (n = 7), extremities (n = 4) and mediastinum (n = 1). Fascicular/spindle histology was predominant in four cases, including one with heterologous lipoblasts in focally myxoid stroma. Four sclerosing cases mainly comprised rounded cells, including one with multinucleated tumour cells. Four cases were histologically hybrid. The only PIK3CA (p.H1047R) mutation was detected in a predominantly spindled MYOD1-p.L122R-mutated case, but not in its laser-microdissected lipoblast-containing area. All MYOD1-mutant cases exhibited diffuse MYOD1 expression but patchy myogenin reactivity. At final follow-up (median = 13.5 months), recurrences (n = 4), metastases (n = 2) or both (n = 1) occurred in seven MYOD1-mutant cases; one had died of disease. Five non-mutated cases were reclassified as spindle embryonal (n = 3), dense embryonal (n = 1) and unclassifiable (n = 1) RMSs. CONCLUSION: MYOD1-mutant RMSs are uncommonly mutated with PIK3CA and behave aggressively with an expanded morphological and genetic spectrum, including lipoblastic differentiation, multinucleated cells and the alternative p.E118K mutation.


Assuntos
Proteína MyoD/genética , Rabdomiossarcoma/genética , Rabdomiossarcoma/patologia , Adolescente , Adulto , Criança , Classe I de Fosfatidilinositol 3-Quinases/genética , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Estudos Retrospectivos , Sarcoma/genética , Sarcoma/patologia , Adulto Jovem
10.
J Microbiol Immunol Infect ; 51(4): 492-499, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28698040

RESUMO

BACKGROUND: The role of class II P fimbriae (P fimbriae II) in diabetic kidney infections is uncertain, although some genetic and epidemiological studies suggest a lower prevalence of P fimbriae II genes in Escherichia coli strains isolated from diabetic patients with complicated kidney infections. METHODS: We inoculated a P fimbriae II deficient E. coli (DH5αT) or an isogenic P fimbriae II expressing transformant (DH5αTP) into the bladders of diabetic and non-diabetic BALB/C mice, and sacrificed them after 3 days. The incidence of bladder or kidney infection (≥103 CFU of E. coli per bladder or kidney), bacteremia (≥102 CFU of E. coli on blood culture plate), kidney pathological score, immunoreactive Histo-score (H-score), and corrected H-score (H-score adjusted for Log10 CFU of bacteria in the kidney) were compared among groups. RESULTS: Diabetic mice were more susceptible to bladder infection than non-diabetic mice with both transformants. The geometric mean of bacteria counts in kidneys was significantly increased only when the diabetic mice were infected with DH5αTP. Among the 4 groups of mice, diabetic mice infected with DH5αTP had the highest incidence of kidney infection and bacteremia, and the highest renal pathology scores. The IL-8 H-score and the corrected IL-6 and IL-8 H-score were significantly lower in diabetic than non-diabetic mice. CONCLUSION: We concluded that P fimbriae II contribute to the pathogenesis and severity of E. coli kidney infections in diabetic mice. An impaired cytokine response may also contribute to the increased incidence and severity of kidney infections in diabetic hosts.


Assuntos
Citocinas/metabolismo , Complicações do Diabetes , Infecções por Escherichia coli/fisiopatologia , Escherichia coli/crescimento & desenvolvimento , Proteínas de Fímbrias/metabolismo , Nefrite/fisiopatologia , Fatores de Virulência/metabolismo , Animais , Carga Bacteriana , Modelos Animais de Doenças , Suscetibilidade a Doenças , Escherichia coli/genética , Escherichia coli/patogenicidade , Feminino , Proteínas de Fímbrias/deficiência , Rim/microbiologia , Rim/patologia , Camundongos Endogâmicos BALB C , Fatores de Virulência/deficiência
11.
Ann Clin Lab Sci ; 46(4): 412-7, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27466302

RESUMO

OBJECTIVE: The Abbott RealTime MTB assay, launched in June 2014, has been shown to have a competitive performance in the detection of the Mycobacterium tuberculosis (MTB) complex in respiratory specimens. The present study was conducted to investigate the usefulness of the Abbott MTB Realtime assay in the detection of MTB in formalin-fixed paraffin-embedded (FFPE) tissues. METHODS: A total of 96 FFPE specimens obtained from microbiologically proven MTB cases (N=60) and nontuberculous Mycobacterium cases (N=36) were analyzed. The performance of the Abbott MTB Realtime assay was compared with that of the Roche Cobas TaqMan MTB assay. RESULTS: The overall sensitivity and specificity of the Abbott assay were 63.3% and 97.2%, respectively, compared with 11.7% and 100% for the Cobas assay. The detection rate of the Abbott assay was much higher among 37 acid-fast-positive specimens than among 23 acid-fast-negative specimens (89.3% versus 21.7%, respectively). The detection rate of the assay was higher among 29 resection specimens than among 31 small biopsy specimens (86.2% versus 41.9%, respectively). CONCLUSION: Our results suggest that the Abbott RealTime MTB assay can be used to differentiate MTB from nontuberculous mycobacterial infections in acid-fast-positive FFPE tissues.


Assuntos
Mycobacterium tuberculosis/isolamento & purificação , Inclusão em Parafina/métodos , Kit de Reagentes para Diagnóstico , Tuberculose Pulmonar/diagnóstico , Tuberculose Pulmonar/microbiologia , Automação , Formaldeído , Humanos , Fixação de Tecidos
12.
Histopathology ; 69(5): 792-801, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27228320

RESUMO

AIMS: BCOR-CCNB3 sarcoma is a genetically defined undifferentiated malignancy with Ewing sarcoma (ES)-like round cells, and preferentially affects the bones of male adolescents. Sarcomas harbouring BCOR-CCNB3 rarely arise from soft tissues; therefore, we aimed to report four cases to expand the clinicopathological spectrum. METHODS AND RESULTS: By reverse transcription polymerase chain reaction and confirmatory sequencing, we detected a BCOR-CCNB3 transcript in primary undifferentiated sarcomas of the deep musculature of four male patients, comprising two teenagers (aged 14 and 17 years) and two adults (aged 34 and 44 years). The tumours originated in the back (n = 2), pelvis (n = 1), and thigh (n = 1), and were 70-140 mm in size (mean, 107 mm). All tumours showed sheets of primitive round or ovoid cells with vesicular nuclei, active mitosis (28-41/10 high-power fields), variably prominent nucleoli, and geographical necrosis. This major component transformed into fascicles of elongated spindle cells with staghorn vessels and a myxoid reticular stroma, accounting for 10-50% of areas. All cases were positive for CD99, three were positive for TLE1, and one was positive for EMA, indicating poorly differentiated synovial sarcomas (PDSSs). Nuclear cyclin B3 reactivity was present in all cases, but not in molecularly confirmed atypical ESs and PDSSs. At the last follow-up (median, 13.5 months), one patient had died of lung metastasis, two were alive with tumours, and one was tumour-free. CONCLUSIONS: BCOR-CCNB3-positive sarcomas may primarily occur in soft tissues of adults and show PDSS-mimicking round-cell and spindle-cell histology with aggressive behaviour. Cyclin B3 is useful for selecting candidates for BCOR-CCNB3 molecular testing.


Assuntos
Biomarcadores Tumorais/análise , Ciclina B/genética , Proteínas Proto-Oncogênicas/genética , Proteínas Repressoras/genética , Sarcoma Sinovial/diagnóstico , Sarcoma/diagnóstico , Neoplasias de Tecidos Moles/diagnóstico , Adolescente , Adulto , Diagnóstico Diferencial , Humanos , Masculino , Proteínas de Fusão Oncogênica/análise , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Sarcoma/genética , Sarcoma/patologia , Sarcoma Sinovial/genética , Sarcoma Sinovial/patologia , Neoplasias de Tecidos Moles/genética , Neoplasias de Tecidos Moles/patologia
13.
Neurologist ; 19(3): 73-8, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25692513

RESUMO

Primary angiitis of the central nervous system is a rare idiopathic inflammation of vessels. We report on a 75-year-old male with primary angiitis of the central nervous system and cerebral amyloid angiopathy. He presented with subacute onset of progressive decline in cognitive functions, followed by confusion and coma. Initial brain magnetic resonance imaging favored meningoencephalitis. There was no improvement after treatment with antibiotics. Final diagnosis was proven by brain biopsy. Corticosteroids were given, but without significant improvement. This case is reported because of its rarity and its clinical presentation.


Assuntos
Angiopatia Amiloide Cerebral/patologia , Vasculite do Sistema Nervoso Central/patologia , Idoso , Encéfalo/patologia , Humanos , Masculino
14.
J Infect Dis ; 209(2): 224-35, 2014 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-23956440

RESUMO

Skin and soft-tissue infections (SSTIs) caused by community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) have emerged as major health problems throughout the world. Most SSTI CA-MRSA strains produce Panton-Valentine leukocidin (PVL), but its contribution to CA-MRSA pathogenesis is poorly defined. Here, we used an endemic PVL-positive SSTI-causing CA-MRSA strain from Taiwan, together with an isogenic PVL-knockout mutant (Δpvl) and complemented PVL-positive derivative, to evaluate the role of PVL in the pathogenesis of CA-MRSA in the RHEK-1 human keratinocyte cell line and a rabbit skin infection model. We found that both PVL-positive CA-MRSA and isogenic Δpvl strains attached and were engulfed into endosomes of RHEK-1 cells within 1 hour following infection. However, by 2 hours after infection PVL-positive CA-MRSA more effectively disrupted endosomes, escaped into the cytoplasm, and replicated intracellularly. By 6 hours after infection, the PVL-positive strain caused significantly more caspase-dependent keratinocyte apoptosis than the isogenic Δpvl mutant. In the rabbit infection model, 1 week following infection the wild-type strain produced significantly more widespread lesions and cell apoptosis than the isogenic Δpvl mutant. These findings indicate that PVL is an important virulence factor that enables CA-MRSA to produce necrotizing skin infections by allowing the bacteria to escape from endosomes, replicate intracellularly, and induce apoptosis.


Assuntos
Apoptose , Toxinas Bacterianas/metabolismo , Endossomos/microbiologia , Exotoxinas/metabolismo , Queratinócitos/microbiologia , Leucocidinas/metabolismo , Staphylococcus aureus Resistente à Meticilina/patogenicidade , Fatores de Virulência/metabolismo , Animais , Bactérias , Linhagem Celular , Infecções Comunitárias Adquiridas/microbiologia , Modelos Animais de Doenças , Feminino , Deleção de Genes , Teste de Complementação Genética , Humanos , Lagomorpha , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Coelhos , Infecções Cutâneas Estafilocócicas/microbiologia , Taiwan , Virulência
15.
Carcinogenesis ; 33(11): 2065-75, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22847181

RESUMO

Growing evidence suggests that Stat3 contributes to chemoresistance. However, the impact of chemotherapy on Stat3 activity is unclear. We found that paclitaxel activated Stat3 in the human lung cancer cell lines PC14PE6AS2 (AS2) and H157, whereas it reduced Stat3 activation in A549 and H460 cells. Pretreatment of AS2 and H157 cells with rotenone, an inhibitor of mitochondrially produced reactive oxygen species (ROS), or carbonyl cyanide p-(trifluoromethoxy)-phenylhydrazone (FCCP), a mitochondrial uncoupler, suppressed the paclitaxel-induced activation of Stat3. Uncoupling protein 2 (UCP-2), located in the inner membrane of the mitochondria, can reduce ROS production in conditions of oxidative stress. UCP-2 protein expression in the four cancer cell lines was higher than that in normal lung epithelial cells (NL-20), but its expression was lower in AS2 and H157 cells relative to A549 and H460 cells. Silencing high UCP-2 expression with small interfering RNA (siRNA) in A549 and H460 cells restored paclitaxel-induced Stat3 activation. In addition, paclitaxel-induced Stat3 activation led to the upregulation of survivin and Mcl-1, which in turn facilitated cell survival. Moreover, the CL1-5 subline had lower UCP-2 expression relative to the parental CL1-0 cells. Treatment with paclitaxel activated Stat3 in CL1-5 but not in CL1-0 cells, whereas in CL1-5 cells, the overexpression of UCP-2 with complementary DNA (cDNA) blocked Stat3 activation. In lung cancer patients, low UCP-2 expression in cancer cells was a predictor of a poor response to chemotherapy. Therefore, UCP-2 modulates the ROS/Stat3 signaling pathway and response to chemotherapy treatment in lung cancer cells. Targeting UCP-2, ROS and Stat3 pathways may improve anticancer therapies.


Assuntos
Adenocarcinoma/patologia , Apoptose/efeitos dos fármacos , Canais Iônicos/metabolismo , Neoplasias Pulmonares/patologia , Proteínas Mitocondriais/metabolismo , Paclitaxel/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Fator de Transcrição STAT3/metabolismo , Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/metabolismo , Adenocarcinoma/mortalidade , Antineoplásicos/farmacologia , Antineoplásicos Fitogênicos/farmacologia , Western Blotting , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Cisplatino/farmacologia , Humanos , Técnicas Imunoenzimáticas , Pulmão/citologia , Pulmão/efeitos dos fármacos , Pulmão/metabolismo , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/mortalidade , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Mitocôndrias/patologia , RNA Interferente Pequeno/genética , Fator de Transcrição STAT3/antagonistas & inibidores , Fator de Transcrição STAT3/genética , Transdução de Sinais/efeitos dos fármacos , Taxa de Sobrevida , Proteína Desacopladora 2
16.
Mol Cell Proteomics ; 11(11): 1320-39, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22896658

RESUMO

Metastasis is a major obstacle that must be overcome for the successful treatment of lung cancer. Proteins secreted by cancer cells may facilitate the progression of metastasis, particularly within the phases of migration and invasion. To discover metastasis-promoting secretory proteins within cancer cells, we used the label-free quantitative proteomics approach and compared the secretomes from the lung adenocarcinoma cell lines CL1-0 and CL1-5, which exhibit low and high metastatic properties, respectively. By employing quantitative analyses, we identified 660 proteins, 68 of which were considered to be expressed at different levels between the two cell lines. High levels of A1AT were secreted by CL1-5, and the roles of A1AT in the influence of lung adenocarcinoma metastasis were investigated. Molecular and pathological confirmation demonstrated that altered expression of A1AT correlates with the metastatic potential of lung adenocarcinoma. The migration and invasion properties of CL1-5 cells were significantly diminished by reducing the expression and secretion of their A1AT proteins. Conversely, the migration and invasion properties of CL1-0 cells were significantly increased through the overexpression and secretion of A1AT proteins. Furthermore, the assembly levels of the metastasis-promoting pericellular fibronectin (FN1), which facilitates colonization of lung capillary endothelia by adhering to the cell surface receptor dipeptidyl peptidase IV (DPP IV), were higher on the surfaces of suspended CL1-5 cells than on those of the CL1-0 cells. This discovery reflects previous findings in breast cancer. In line with this finding, FN1 assembly and the lung colonization of suspended CL1-5 cells were inhibited when endogenous A1AT protein was knocked down using siRNA. The major thrust of this study is to demonstrate the effects of coupling the label-free proteomics strategy with the secretomes of cancer cells that differentially exhibit invasive and metastatic properties. This provides a new opportunity for the effective identification of metastasis-associated proteins that are secreted by cancer cells and promote experimental metastasis.


Assuntos
Adenocarcinoma/metabolismo , Adenocarcinoma/patologia , Movimento Celular , Fibronectinas/metabolismo , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Pulmão/patologia , Proteínas de Neoplasias/metabolismo , alfa 1-Antitripsina/metabolismo , Adenocarcinoma de Pulmão , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Meios de Cultivo Condicionados/farmacologia , Humanos , Imuno-Histoquímica , Pulmão/metabolismo , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica , Metástase Neoplásica , Polimerização/efeitos dos fármacos , Reprodutibilidade dos Testes
17.
APMIS ; 119(8): 543-50, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21749455

RESUMO

We investigated the prevalence of metallo-ß-lactamases (MBLs) among 1,827 Enterobacteriaceae isolates collected in 2006 and evaluated the VITEK 2 microbiology system, modified Hodge test, and 2 combined disk tests as the screening tools for MBLs by using these isolates and 77 previously characterized IMP-8 producers. The IMP-8 MBL was identified in 18 isolates of 2006, and the IMP-8-positive isolates represented 0.2%, 1.1%, and 5.0% of all Escherichia coli, Klebsiella pneumoniae, and Enterobacter cloacae isolates, respectively. Only one-third of all MBL producers could be recognized by either VITEK 2 or the Hodge test. MBL production could be identified in 38 (40%) of the 95 IMP-8-producing isolates by the combined disk test using meropenem disks supplemented by phenylboronic acid and EDTA, and only 2 (2.1%) isolates gave positive results in the combined disk test using meropenem disks supplemented with dipicolinic acid. Of all IMP-8 producers, 37.9%, 50.5%, and 32.6% were nonsusceptible to tigecycline, fluoroquinolones, and both, respectively. In conclusion, this study demonstrated the lack of distinct phenotypes that could be easily identified among the IMP-8-producing Enterobacteriaceae isolates at a Taiwanese hospital. Continuous surveillance and monitoring are needed because the widespread of tigecycline- and fluoroquinolone-coresistant MBL producers may become a serious therapeutic problem.


Assuntos
Antibacterianos/farmacologia , Infecções por Enterobacteriaceae/microbiologia , Enterobacteriaceae/enzimologia , Minociclina/análogos & derivados , beta-Lactamases/biossíntese , DNA Bacteriano/química , DNA Bacteriano/genética , Farmacorresistência Bacteriana , Eletroforese em Gel de Campo Pulsado , Enterobacteriaceae/genética , Enterobacteriaceae/isolamento & purificação , Infecções por Enterobacteriaceae/tratamento farmacológico , Humanos , Testes de Sensibilidade Microbiana , Minociclina/farmacologia , Fenótipo , Reação em Cadeia da Polimerase , Taiwan , Tigeciclina , beta-Lactamases/genética
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