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1.
EBioMedicine ; 102: 105050, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38490105

RESUMO

BACKGROUND: Noninvasive in vivo cell tracking is valuable in understanding the mechanisms that enhance anti-cancer immunity. We have recently developed a new method called phototruncation-assisted cell tracking (PACT), that uses photoconvertible cell tracking technology to detect in vivo cell migration. This method has the advantages of not requiring genetic engineering of cells and employing tissue-penetrant near-infrared light. METHODS: We applied PACT to monitor the migration of immune cells between a tumour and its tumour-draining lymph node (TDLN) after near-infrared photoimmunotherapy (NIR-PIT). FINDINGS: PACT showed a significant increase in the migration of dendritic cells (DCs) and macrophages from the tumour to the TDLN immediately after NIR-PIT. This migration by NIR-PIT was abrogated by inhibiting the sphingosine-1-phosphate pathway or Gαi signaling. These results were corroborated by intranodal immune cell profiles at two days post-treatment; NIR-PIT significantly induced DC maturation and increased and activated the CD8+ T cell population in the TDLN. Furthermore, PACT revealed that NIR-PIT significantly enhanced the migration of CD8+ T cells from the TDLN to the tumour four days post-treatment, which was consistent with the immunohistochemical assessment of tumour-infiltrating lymphocytes and tumour regression. INTERPRETATION: Immune cells dramatically migrated between the tumour and TDLN following NIR-PIT, indicating its potential as an immune-stimulating therapy. Also, PACT is potentially applicable to a wide range of immunological research. FUNDING: This work was supported by the Intramural Research Program of the National Institutes of Health, National Cancer Institute, Centre for Cancer Research (grant number: ZIA BC011513 and ZIA BC011506).


Assuntos
Linfócitos T CD8-Positivos , Carbocianinas , Rastreamento de Células , Humanos , Linhagem Celular Tumoral , Fototerapia/métodos , Imunoterapia/métodos , Ensaios Antitumorais Modelo de Xenoenxerto
2.
Cancer Lett ; 585: 216606, 2024 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-38272345

RESUMO

Enfortumab vedotin (EV), an antibody-drug conjugate (ADC) that targets Nectin-4, has shown promising results in the treatment of bladder cancer. However, multiple resistance mechanisms that are unique to ADCs limit the therapeutic potential of EV in clinical practice. Here, we developed and tested a Nectin-4-targeted near-infrared photoimmunotherapy (NIR-PIT) that utilizes the same target as EV but utilizes a distinct cytotoxic and immunotherapeutic pathway in preclinical models of bladder cancer. NIR-PIT was effective in vitro against luminal subtype human bladder cancer cell lines (RT4, RT112, MGH-U3, SW780, and HT1376-luc), but not against other subtype cell lines (UMUC3 and T24). In vivo, the tumor site was clearly visible by Nectin-4-IR700 fluorescence 24 h after its administration, suggesting the potential as an intraoperative imaging modality. NIR-PIT significantly suppressed tumor growth and prolonged survival in SW780 and RT112 xenograft models. Weekly treatment with NIR-PIT further improved tumor control in RT112 xenograft models. The effectiveness of NIR-PIT was also confirmed in HT1376-luc orthotopic xenograft models. Histological analysis verified that NIR-PIT induced a significant pathologic response. Taken together, Nectin-4-targeted NIR-PIT shows promise as a treatment for luminal subtype bladder cancers.


Assuntos
Fármacos Fotossensibilizantes , Neoplasias da Bexiga Urinária , Humanos , Nectinas/genética , Fármacos Fotossensibilizantes/farmacologia , Fármacos Fotossensibilizantes/uso terapêutico , Linhagem Celular Tumoral , Fototerapia/métodos , Imunoterapia/métodos , Neoplasias da Bexiga Urinária/tratamento farmacológico , Ensaios Antitumorais Modelo de Xenoenxerto
3.
Int J Cancer ; 154(5): 895-911, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-37907830

RESUMO

Epstein-Barr virus (EBV)-associated nasopharyngeal carcinoma (NPC) cells have high metastatic potential. Recent research has revealed that the interaction of between tumor cells and the surrounding stroma plays an important role in tumor invasion and metastasis. In this study, we showed the prognostic value of expression of SPARC, an extracellular matrix protein with multiple cellular functions, in normal adjacent tissues (NAT) surrounding NPC. In the immunohistochemical analysis of 51 NPC biopsy specimens, SPARC expression levels were significantly elevated in the NAT of EBER (EBV-encoded small RNA)-positive NPC compared to that in the NAT of EBER-negative NPC. Moreover, increased SPARC expression in NAT was associated with a worsening of overall survival. The enrichment analysis of RNA-seq of publicly available NPC and NAT surrounding NPC data showed that high SPARC expression in NPC was associated with epithelial mesenchymal transition promotion, and there was a dynamic change in the gene expression profile associated with interference of cellular proliferation in NAT, including SPARC expression. Furthermore, EBV-positive NPC cells induce SPARC expression in normal nasopharyngeal cells via exosomes. Induction of SPARC in cancer-surrounding NAT cells reduced intercellular adhesion in normal nasopharyngeal structures and promoted cell competition between cancer cells and normal epithelial cells. These results suggest that epithelial cells loosen their own binding with the extracellular matrix as well as stromal cells, facilitating the invasion of tumor cells into the adjacent stroma by activating cell competition. Our findings reveal a new mechanism by which EBV creates a pro-metastatic microenvironment by upregulating SPARC expression in NPC.


Assuntos
Infecções por Vírus Epstein-Barr , Exossomos , Neoplasias Nasofaríngeas , Humanos , Carcinoma Nasofaríngeo/metabolismo , Herpesvirus Humano 4/genética , Neoplasias Nasofaríngeas/patologia , Prognóstico , Exossomos/metabolismo , Microambiente Tumoral , Osteonectina/genética , Osteonectina/metabolismo
4.
Cancer Sci ; 114(12): 4654-4663, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37817415

RESUMO

Epidermal growth factor receptor (EGFR) has emerged as an important therapeutic target in many cancers, and overexpression of EGFR is frequently observed in hepatocellular carcinomas (HCCs). Near-infrared photoimmunotherapy (NIR-PIT) is a new anticancer treatment that selectively damages the cell membrane of cancer cells after NIR light-induced photochemical reaction of IR700, which is bound to a targeting antibody on the cell membrane. NIR-PIT using cetuximab-IR700 has already been approved in Japan, is under review by the US Food and Drug Administration (FDA) for advanced head and neck cancers, and its safety has been established. However, EGFR has not been investigated as a target in NIR-PIT in HCCs. Here, we investigate the application of NIR-PIT using cetuximab-IR700 to HCCs using xenograft mouse models of EGFR-expressing HCC cell lines, Hep3B, HuH-7, and SNU-449. In vitro NIR-PIT using EGFR-targeted cetuximab-IR700 killed cells in a NIR light dose-dependent manner. In vivo NIR-PIT resulted in a delayed growth compared with untreated controls. In addition, in vivo NIR-PIT in both models showed histological signs of cancer cell damage, such as cytoplasmic vacuolation and nuclear dysmorphism. A significant decrease in Ki-67 positivity was also observed after NIR-PIT, indicating decreased cancer cell proliferation. This study suggests that NIR-PIT using cetuximab-IR700 has potential for the treatment of EGFR-expressing HCCs.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Animais , Camundongos , Cetuximab/farmacologia , Cetuximab/uso terapêutico , Carcinoma Hepatocelular/tratamento farmacológico , Fármacos Fotossensibilizantes , Linhagem Celular Tumoral , Neoplasias Hepáticas/tratamento farmacológico , Imunoterapia/métodos , Receptores ErbB , Ensaios Antitumorais Modelo de Xenoenxerto
6.
Cancer Sci ; 113(7): 2446-2456, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35485636

RESUMO

Nasopharyngeal carcinoma (NPC) is caused by infection with Epstein-Barr virus (EBV) and endemic in certain geographic regions. EBV lytic gene, BALF2, closely associates with viral reactivation and BALF2 gene variation, the H-H-H strain, causes NPC in endemic region, southern China. Here, we investigate whether such EBV variations also affect NPC in a non-endemic region, Japan. Viral genome sequencing with 47 EBV isolates of Japanese NPC were performed and compared with those of other EBV-associated diseases from Japan or NPC in Southern China. EBV genomes of Japanese NPC are different from those of other diseases in Japan or endemic NPC; Japanese NPC was not affected by the endemic strain (the BALF2 H-H-H) but frequently carried the type 2 EBV or the strain with intermediate risk of endemic NPC (the BALF2 H-H-L). Seven single nucleotide variations were specifically associated with Japanese NPC, of which six were present in both type 1 and 2 EBV genomes, suggesting the contribution of the type 2 EBV-derived haplotype. This observation was supported by a higher viral titer and stronger viral reactivation in NPC with either type 2 or H-H-L strains. Our results highlight the importance of viral strains and viral reactivation in the pathogenesis of non-endemic NPC.


Assuntos
Infecções por Vírus Epstein-Barr , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas , China/epidemiologia , Infecções por Vírus Epstein-Barr/complicações , Genoma Viral , Herpesvirus Humano 4/genética , Humanos , Carcinoma Nasofaríngeo/patologia , Carcinoma Nasofaríngeo/virologia , Neoplasias Nasofaríngeas/patologia , Neoplasias Nasofaríngeas/virologia
7.
BMC Surg ; 22(1): 50, 2022 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-35148723

RESUMO

BACKGROUND: Surgery to prevent aspiration has complications related to tracheostomy tube, such as the trachea-brachiocephalic artery fistula. Glottic closure procedure makes tracheostoma at a position higher than the first ring of the trachea and theoretically has a potential to prevent such complications owing to a longer distance between the tip of tracheostomy tube and the tracheal membrane adjacent to the brachiocephalic artery. Our aim is to evaluate the safety of glottic closure in neurologically impaired patients by comparing outcomes with laryngotracheal separation. METHODS: This study is a single-center retrospective study from 2004 to 2019, using data of 15 and 12 patients who underwent glottic closure (GC) and laryngotracheal separation (LTS). The primary outcome was the incidence of postoperative complications induced by tracheostomy tube placement and adjustment of the tracheostomy tube position to prevent these complications, such as by converting to a length-adjustable tube and/or placing gauze between the skin and tube flange. Additionally, we analyzed the anatomical relationship between the tracheostomy tube tip and brachiocephalic artery and measured the distance between them using postoperative CT images. RESULTS: No patients in either group had trachea-brachiocephalic artery fistula. Erosion or granuloma formation occurred in 1 patient (7%) and 4 patients (33%) in the GC and LTS groups, respectively. Adjustment of the tracheostomy tube was needed in 2 patients (13%) and 6 patients (50%) in the GC and LTS groups. CT revealed a higher proportion of patients with the tracheostomy tube tip superior to the brachiocephalic artery in GC than LTS group. The mean tracheostoma-brachiocephalic artery distance was 40.8 and 32.4 mm in the GC and LTS groups. CONCLUSIONS: Glottic closure reduces the risk of postoperative complications related to a tracheostomy tube. This may be due to the higher position of the tracheostoma at the level of the cricoid cartilage, increasing the distance between the tracheostoma and brachiocephalic artery.


Assuntos
Tronco Braquiocefálico , Traqueostomia , Tronco Braquiocefálico/cirurgia , Humanos , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/prevenção & controle , Estudos Retrospectivos , Traqueia , Traqueostomia/efeitos adversos
8.
Microorganisms ; 9(3)2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33804064

RESUMO

Nasopharyngeal carcinoma (NPC) is an Epstein-Barr virus (EBV)-associated malignancy. The principal oncogene of EBV, latent membrane protein 1 (LMP1), induces the expression of programmed death-ligand 1 (PD-L1), which is an immunosuppressive transmembrane protein and a promising therapeutic target for various malignancies. Recent studies have revealed an association between the level of soluble PD-L1 (sPD-L1) and disease progression. However, the role of sPD-L1 in NPC or its relevance to LMP1 has not been elucidated. This study aimed to examine whether LMP1 induces sPD-L1 in vitro and analyze the clinical relevance of LMP1, PD-L1, and sPD-L1 in NPC patients. Analysis of nasopharyngeal cell lines revealed that LMP1 induces both cellular PD-L1 and sPD-L1. Analysis of biopsy specimens from 32 NPC patients revealed that LMP1 expression was significantly correlated with PD-L1 expression. Finally, the serum sPD-L1 level in NPC patients was higher than that in the controls. Moreover, the sPD-L1 level in the advanced stage was higher than that in the early stage. However, LMP1 expression, PD-L1 expression, and sPD-L1 levels were not associated with prognosis. These results suggest that LMP1 induces both sPD-L1 and PD-L1, which are associated with NPC progression.

9.
Materials (Basel) ; 14(2)2021 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-33435425

RESUMO

Diamond-like carbon (DLC) films have been extensively applied in industries owing to their excellent characteristics such as high hardness. In particular, there is a growing demand for their use as protective films for mechanical parts owing to their excellent wear resistance and low friction coefficient. DLC films have been deposited by various methods and many deviate from the DLC regions present in the ternary diagrams proposed for sp3 covalent carbon, sp2 covalent carbon, and hydrogen. Consequently, redefining the DLC region on ternary diagrams using DLC coatings for mechanical and electrical components is urgently required. Therefore, we investigate the sp3 ratio, hydrogen content, and other properties of 74 types of amorphous carbon films and present the classification of amorphous carbon films, including DLC. We measured the sp3 ratios and hydrogen content using near-edge X-ray absorption fine structure and Rutherford backscattering-elastic recoil detection analysis under unified conditions. Amorphous carbon films were widely found with nonuniform distribution. The number of carbon atoms in the sp3 covalent carbon without bonding with hydrogen and the logarithm of the hydrogen content were inversely proportional. Further, we elucidated the DLC regions on the ternary diagram, classified the amorphous carbon films, and summarized the characteristics and applications of each type of DLC.

10.
Auris Nasus Larynx ; 48(6): 1221-1225, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32859443

RESUMO

Vertical partial laryngectomy is a well-established surgical procedure for early glottic cancers with acceptable functional and oncological outcomes. However, on a long-term basis, aspiration might be a serious problem with aging. Here we presented two cases of refractory aspiration pneumonia after vertical laryngectomy. Case 1: A 76-year old gentleman with a past history of malignant lymphoma treated by chemotherapy and radiotherapy had glottic cancer, which was treated by repeated vertical partial laryngectomies. Although glottic caner had been well controlled, he started to suffer from refractory aspiration pneumonia. Since his cervical skin was very thin and hard and his general condition was poor, we employed modified Kano's method for glottic closure. Case 2: A 87-year old Japanese male had a past history of glottic cancer treated by radiotherapy and vertical partial laryngectomy. He was repeatedly hospitalized for severe aspiration pneumonia. At the age of 87, he had second primary oropharyngeal cancer. Kano's method was simultaneously performed at the time of resection of oropharyngeal cancer. Postoperative courses were uneventful without sign of leakage in both cases. The patients started oral intake 2 weeks after the surgery. They have been alive without aspiration pneumonia and takes normal diet.


Assuntos
Glote/cirurgia , Laringectomia/efeitos adversos , Procedimentos Cirúrgicos Otorrinolaringológicos/métodos , Pneumonia Aspirativa/cirurgia , Idoso , Idoso de 80 Anos ou mais , Cinerradiografia , Glote/diagnóstico por imagem , Humanos , Neoplasias Laríngeas/cirurgia , Masculino , Pneumonia Aspirativa/diagnóstico por imagem , Pneumonia Aspirativa/etiologia
11.
Microorganisms ; 8(9)2020 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-32842711

RESUMO

Human papillomavirus (HPV) infection is now identified as a major etiologic factor for oropharyngeal cancer (OPC), and HPV positivity is well established better prognostic marker in OPC. Now, predictable markers for the prognosis of the patients who are stratified by HPV has been investigated in. Semaphorin 3A (SEMA3A) is a well-known axon guidance molecule in the nervous system. It is also known as a tumor suppressor in various cancers. In the present study, we examined the relationships between SEMA3A and clinicopathologic features, especially HPV status, and neoangiogenesis, and its prognostic significance for OPC patients. Thirty-two OPC patients and 17 normal patients were analyzed for SEMA3A expression by immunohistochemical analysis. We also analyzed 22 OPC specimens for CD34 expression as a marker of neoangiogenesis. SEMA3A was significantly downregulated in OPC compared with chronic tonsillitis tissues (p = 0.005). SEMA3A expression was negatively correlated with CD34 expression (r = -0.466, p = 0.033). Moreover, the higher SEMA3A expression cohort showed better survival than the lower SEMA3A expression cohort regardless of HPV status (p = 0.035). These results suggest that SEMA3A expression is a prognostic marker for survival regardless of HPV status and is associated with anti-angiogenesis in OPC.

12.
Microorganisms ; 8(3)2020 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-32192122

RESUMO

Semaphorins were discovered as guidance signals that mediate neural development. Recent studies suggest that semaphorin 3A (Sema3A), a member of the semaphorin family, is involved in the development of several cancers. This study aimed to analyze the association of Sema3A with the clinical features of nasopharyngeal carcinoma (NPC), an Epstein-Barr virus-associated carcinoma, and the Epstein-Barr virus primary oncogene latent membrane protein 1 (LMP1). The expression of Sema3A and LMP1 was immunohistochemically examined in the 35 NPC specimens. The mean expression scores for Sema3A and LMP1 were 20.8% ± 14.5% and 13.9% ± 14.8%, respectively. The expression of Sema3A significantly correlated with that of LMP1 (r = 0.41, p = 0.014). In addition, the Sema3A high cohort showed significantly poorer prognosis than the Sema3A low cohort. Sema3A expression was higher in the LMP1-positive KH-1 and KR-4 cell lines compared to the LMP1-negative HeLa cells. Overexpression of LMP1 in the LMP1-negative AdAH cell line upregulated Sema3A expression, both at the transcriptional and translational level. Finally, Sema3A expression was associated with poor prognosis in patients with NPC. Our data suggest that LMP1 induces the expression of Sema3A, which may promote tumor progression in NPC.

13.
Int J Cancer ; 145(6): 1547-1557, 2019 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-31228270

RESUMO

Human papillomavirus (HPV) has been identified as a causative agent of cervical cancer and oropharyngeal cancer (OPC). Intriguingly, estrogen and HPV were shown to play synergistic roles in cervical carcinogenesis. We recently demonstrated that the apolipoprotein B mRNA-editing catalytic polypeptide 3 (APOBEC3, A3) family, which is inducible by estrogen, could lead to HPV DNA hypermutation and cause viral DNA integration. In the present study, we examined the relationships between estrogen-estrogen receptor α (ERα) and A3s in HPV-positive OPC. ERα expression was associated with HPV positivity in OPC biopsy samples using immunohistochemical analysis and reverse-transcription quantitative polymerase chain reaction. In addition, ERα was significantly associated with improved overall survival in HPV-positive OPC (hazard ratio, 0.26; p = 0.029). APOBEC3A (A3A) mRNA was induced by estrogen in HPV and ERα-positive OPC cells. Furthermore, A3A mRNA and protein expression were significantly higher in ERα-positive cases than in ERα-negative ones, among HPV-positive biopsy samples (p = 0.037 and 0.047). These findings suggest that A3A is associated with a good prognosis in ERα-positive OPC, and indicate the prognostic significance of ERα in HPV-positive OPC. This is the first study to demonstrate the prognostic role of ERα in HPV-positive OPC.


Assuntos
Alphapapillomavirus/isolamento & purificação , Receptor alfa de Estrogênio/metabolismo , Neoplasias Orofaríngeas/patologia , Idoso , Linhagem Celular Tumoral , Citidina Desaminase/genética , Citidina Desaminase/metabolismo , Estrogênios/metabolismo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Orofaríngeas/metabolismo , Neoplasias Orofaríngeas/virologia , Prognóstico , Proteínas/genética , Proteínas/metabolismo , RNA Mensageiro/metabolismo , Transdução de Sinais
14.
Laryngoscope Investig Otolaryngol ; 4(2): 246-249, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31024995

RESUMO

BACKGROUND: In 2008, Kano developed a new laryngeal closure technique (Kano's method) for the treatment of severe aspiration. The aim of this study was to evaluate the safety and efficacy of this technique in patients with head and neck cancer. METHODS: Since June 2014 until March 2018, six patients underwent Kano's method for management of severe aspiration after the treatment of head and neck cancers. The anterior parts of the thyroid and the cricoid cartilages were excised widely. The glottis was closed by suturing bilateral vocal folds and reinforced by the sternohyoid muscle. A tracheostoma was created with skin flaps, subglottic mucosal flaps, and stumps of cricoid and trachea cartilages. RESULTS: No severe complications were observed after the surgery. Oral intake improved without developing aspiration. CONCLUSIONS: Kano's method can provide satisfactory functional results with minimal invasion for treating severe aspiration after advanced surgery, chemotherapy, and/or chemoradiotherapy, in patients with head and neck cancer. LEVEL OF EVIDENCE: 4.

15.
Ann Otol Rhinol Laryngol ; 128(2): 96-103, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30347994

RESUMO

OBJECTIVES:: The aim of this study was to elucidate the utility of the Kano method with surgical closure of the larynx by cricoid cartilage removal in improving quality of life in patients with severe dysphagia and their caregivers. METHODS:: Nine patients with severe dysphagia who underwent the Kano method were evaluated for oral intake and activities of daily living using the functional oral intake scale and the Barthel index, respectively, as indices of quality of life. Additionally, nutritional status, inflammation, and postoperative complications were assessed. Furthermore, 7 family caregivers were queried regarding frequency of sputum suction, mood of family caregivers, and postoperative satisfaction. RESULTS:: Functional oral intake scale and Barthel index scores as well as inflammation improved significantly after surgery ( P < .05). There were no severe complications or other complications requiring surgical intervention. The frequency of sputum suction was reduced postoperatively ( P < .05). The mood of family caregivers was significantly improved and satisfaction level was high postoperatively. CONCLUSIONS:: Surgical closure of the larynx is an appropriate choice for patients with irreversible severe dysphagia and impaired articulation or vocal function because quality of life is improved for both patients and family caregivers and the satisfaction of family caregivers is sufficient.


Assuntos
Cuidadores/psicologia , Cartilagem Cricoide/cirurgia , Transtornos de Deglutição/cirurgia , Laringe/cirurgia , Satisfação Pessoal , Qualidade de Vida , Atividades Cotidianas , Idoso , Idoso de 80 Anos ou mais , Transtornos de Deglutição/etiologia , Transtornos de Deglutição/psicologia , Família/psicologia , Feminino , Humanos , Inflamação/etiologia , Masculino , Pessoa de Meia-Idade , Avaliação Nutricional , Satisfação do Paciente , Pneumonia Aspirativa/prevenção & controle , Pneumonia Aspirativa/terapia , Complicações Pós-Operatórias , Estudos Retrospectivos , Sucção
16.
J Toxicol Sci ; 43(7): 443-450, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29973476

RESUMO

The nuclear receptor pregnane X receptor (PXR) plays a major role in the xenobiotic-induced expression of drug-metabolizing enzymes. PXR activation is also associated with several adverse events in the liver. Especially, the receptor enhances hepatocyte proliferation mediated by chemical liver tumor promoters, suggesting that exposure to PXR activators increases the risk of liver cancer. In this study, we have investigated the influences of food additives on PXR to understand their potential adverse effects when they are taken in combination with other chemical compounds. We first screened 25 food additives and related compounds for their PXR-activating ability using reporter assays in HepG2 cells expressing mouse PXR, and found that imazalil dose-dependently activated mouse PXR. Next, to investigate whether imazalil could activate mouse PXR in vivo, mice were treated with imazalil and we found that imazalil treatment increased hepatic mRNA levels of Cyp3a11, a PXR target gene. Finally, to investigate the influence of imazalil exposure on the hepatocyte proliferation induced by nuclear receptor constitutive active/androstane receptor (CAR), mice were treated with imazalil with or without mouse CAR activator TCPOBOP. Although imazalil alone did not induce hepatocyte proliferation, co-treatment with imazalil facilitated the TCPOBOP-dependent proliferation, indicated by the increases in cell proliferation marker levels, Ki-67-positive nuclei and Mcm2 mRNA levels. These results suggest that in mice imazalil activates PXR to enhance hepatocyte proliferation mediated by CAR-activating liver tumor promoters.


Assuntos
Proliferação de Células/efeitos dos fármacos , Proliferação de Células/genética , Aditivos Alimentares/efeitos adversos , Hepatócitos/citologia , Hepatócitos/efeitos dos fármacos , Imidazóis/farmacologia , Receptores de Esteroides/fisiologia , Animais , Carcinógenos , Receptor Constitutivo de Androstano , Citocromo P-450 CYP3A/genética , Relação Dose-Resposta a Droga , Células Hep G2 , Humanos , Antígeno Ki-67 , Neoplasias Hepáticas/induzido quimicamente , Masculino , Proteínas de Membrana/genética , Camundongos Endogâmicos C57BL , Componente 2 do Complexo de Manutenção de Minicromossomo/genética , Componente 2 do Complexo de Manutenção de Minicromossomo/metabolismo , Receptor de Pregnano X , Piridinas/farmacologia , RNA Mensageiro/metabolismo , Receptores Citoplasmáticos e Nucleares/fisiologia , Receptores de Esteroides/metabolismo
17.
Toxicol Sci ; 165(2): 408-419, 2018 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-29893953

RESUMO

Constitutive androstane receptor (CAR) is a xenobiotic-responsive nuclear receptor that is highly expressed in the liver. CAR activation induces hepatocyte proliferation and hepatocarcinogenesis in rodents, but the mechanisms remain unclear. In this study, we investigated the association of CAR-dependent cell proliferation with Yes-associated protein (YAP), which is a transcriptional cofactor controlling organ size and cell growth through the interaction with various transcriptional factors including TEA domain family member (TEAD). In mouse livers, 1,4-bis-(2-[3,5-dichloropyridyloxy])benzene (TCPOBOP) (a mouse CAR [mCAR] activator) treatment increased the nuclear YAP accumulation and mRNA levels of YAP target genes as well as cell-cycle related genes along with liver hypertrophy and verteporfin (an inhibitor of YAP/TEAD interaction) cotreatment tended to attenuate them. Furthermore, in cell-based reporter gene assays, CAR activation enhanced the YAP/TEAD-dependent transcription. To investigate the role of YAP/TEAD activation in the CAR-dependent hepatocyte proliferation, we sought to establish an in vitro system completely reproducing CAR-dependent cell proliferation. Since CAR was only slightly expressed in cultured mouse primary hepatocytes compared with mouse livers and no proliferation was observed after treatment with TCPOBOP, we overexpressed CAR using mCAR expressing adenovirus (Ad-mCAR-V5) in mouse primary hepatocytes. Ad-mCAR-V5 infection and TCPOBOP treatment induced hepatocyte proliferation. Similar results were obtained with immortalized normal mouse hepatocytes as well. In the established in vitro system, CAR-dependent proliferation was strongly inhibited by Yap knockdown and completely abolished by verteporfin treatment. Our present results obtained in in vivo and in vitro experiments suggest that YAP/TEAD activation plays key roles in CAR-dependent proliferation of murine hepatocytes.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proliferação de Células , Hepatócitos/metabolismo , Fígado/metabolismo , Fosfoproteínas/metabolismo , Receptores Citoplasmáticos e Nucleares/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Animais , Proteínas de Ciclo Celular , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Receptor Constitutivo de Androstano , Expressão Gênica/efeitos dos fármacos , Hepatócitos/efeitos dos fármacos , Hepatócitos/patologia , Hipertrofia , Fígado/efeitos dos fármacos , Fígado/patologia , Masculino , Camundongos Endogâmicos C57BL , Fosfoproteínas/genética , Cultura Primária de Células , Piridinas/farmacologia , Receptores Citoplasmáticos e Nucleares/genética , Verteporfina/farmacologia , Proteínas de Sinalização YAP
18.
Sci Rep ; 8(1): 918, 2018 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-29343743

RESUMO

Activation-induced cytidine deaminase (AID) and apolipoprotein B mRNA-editing catalytic polypeptide 3 (A3) family are cytidine deaminases that play critical roles in B-cell maturation, antiviral immunity and carcinogenesis. Adenoids and palatine tonsils are secondary lymphoid immune organs, in which AID and A3s are thought to have several physiological or pathological roles. However, the expression of AID or A3s in these organs has not been investigated. Therefore, we investigated the expression profiles of AID and A3s, using 67 samples of adenoids and palatine tonsils from patients, with reverse transcription quantitative polymerase chain reaction (RT-qPCR) and immunohistochemical analyses. AID and A3s expression levels in the adenoids and the palatine tonsils of the same individual significantly correlated with each other. Of note, AID expression level in the adenoids negatively correlated with the age (r = -0.373, P = 0.003). The younger group with adenoid vegetation and tonsillar hypertrophy showed more abundant AID expression than the older group with recurrent tonsillitis and peritonsillar abscesses (P = 0.026). Moreover, immunohistochemical analysis revealed the distribution of AID and A3s in the epithelial cells as well as germinal centres. The localisation of AID expression and its relation to age may contribute to adenoid vegetation and inflammation.


Assuntos
Citidina Desaminase/metabolismo , Citosina Desaminase/metabolismo , Tonsila Palatina/metabolismo , Desaminases APOBEC , Tonsila Faríngea/metabolismo , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Feminino , Humanos , Hipertrofia/metabolismo , Masculino , Pessoa de Meia-Idade , Adulto Jovem
19.
Pathol Int ; 67(9): 461-466, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28712115

RESUMO

Interferon regulatory factor 7 (IRF7) has oncogenic properties in several malignancies such as Epstein-Barr virus (EBV)-associated lymphoma. However, there is no evidence whether IRF7 is associated with the oncogenesis of nasopharyngeal cancer (NPC), the pathogenesis of which is closely associated with EBV. Herein, we report that expression of IRF7 was increased in normal nasopharyngeal cells that expressed the EBV principal oncoprotein, latent membrane protein 1 (LMP1). In addition, IRF7 was mainly expressed in the nucleus in both normal nasopharyngeal cells and nasopharyngeal cancer cells that expresses LMP1. On immunohistochemical analysis, IRF7 was predominantly localized in the nucleus in biopsy samples of NPC tissues. In total, IRF7 expression was detected with 36 of 49 specimens of these tissues. Furthermore, the expression score of IRF7 correlated with the expression score of LMP1. Moreover, the expression score of IRF7 is associated with cervical lymph-node metastasis, which reflects the highly metastatic nature of this cancer. Taken together, our results suggest that expression of IRF7 is one of the metastatic effectors of LMP1 signalling in EBV-associated NPC.


Assuntos
Fator Regulador 7 de Interferon/biossíntese , Neoplasias Nasofaríngeas/patologia , Neoplasias Nasofaríngeas/virologia , Proteínas da Matriz Viral/biossíntese , Adulto , Idoso , Biomarcadores Tumorais/análise , Infecções por Vírus Epstein-Barr/complicações , Feminino , Humanos , Metástase Linfática/patologia , Masculino , Pessoa de Meia-Idade , Neoplasias Nasofaríngeas/metabolismo , Adulto Jovem
20.
Sci Rep ; 7: 46394, 2017 04 12.
Artigo em Inglês | MEDLINE | ID: mdl-28401962

RESUMO

The achievement of the superlubricity regime, with a friction coefficient below 0.01, is the Holy Grail of many tribological applications, with the potential to have a remarkable impact on economic and environmental issues. Based on a combined high-resolution photoemission and soft X-ray absorption study, we report that superlubricity can be realized for engineering applications in bearing steel coated with ultra-smooth tetrahedral amorphous carbon (ta-C) under oleic acid lubrication. The results show that tribochemical reactions promoted by the oil lubrication generate strong structural changes in the carbon hybridization of the ta-C hydrogen-free carbon, with initially high sp3 content. Interestingly, the macroscopic superlow friction regime of moving mechanical assemblies coated with ta-C can be attributed to a few partially oxidized graphene-like sheets, with a thickness of not more than 1 nm, formed at the surface inside the wear scar. The sp2 planar carbon and oxygen-derived species are the hallmark of these mesoscopic surface structures created on top of colliding asperities as a result of the tribochemical reactions induced by the oleic acid lubrication. Atomistic simulations elucidate the tribo-formation of such graphene-like structures, providing the link between the overall atomistic mechanism and the macroscopic experimental observations of green superlubricity in the investigated ta-C/oleic acid tribological systems.

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