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71.
Yu Liu Xianghong Wang Angela K F Lo Yong Chuan Wong Annie L M Cheung Sai Wah Tsao 《Journal of medical virology》2002,66(1):63-69
Nasopharyngeal carcinoma is closely associated with Epstein-Barr virus (EBV) and the EBV encoded latent membrane protein-1 expression (LMP1) is commonly found in the tumour cells. LMP1 has been shown to be involved in modulation of cell growth in B cells but the biological properties of LMP1 expression in nasopharyngeal carcinoma cells are less defined. In this study, a full length LMP1 gene was introduced into an EBV negative nasopharyngeal carcinoma cell line, CNE2, and five LMP1-expressing clones were isolated. Expression of LMP1 did not confer cell growth advantage in CNE2 cells; instead, it induced growth inhibition both in vitro and in vivo. In addition, the LMP1 transfected cells were more susceptible to cisplatin-induced cell death and showed 1.4-4.0-fold increased sensitivity to cisplatin compared to the vector infected control clones. The effect of LMP1 on the balance of Bcl-2 and Bax ratio may play a role in inducing susceptibility to cisplatin-induced cell death. These results demonstrated that LMP1 did not confer growth advantage in CNE2 cells, suggesting that expression of LMP1 may not be crucial in sustaining cell growth in established cell lines. Alternatively, LMP1 alone may not be sufficient to facilitate nasopharyngeal carcinoma cell growth and additional oncogenic factors may be needed along with LMP1 in modulating the malignant property of nasopharyngeal carcinoma. 相似文献
72.
Oncogenic S1P signalling in EBV‐associated nasopharyngeal carcinoma activates AKT and promotes cell migration through S1P receptor 3 下载免费PDF全文
Hui Min Lee Kwok‐Wai Lo Wenbin Wei Sai Wah Tsao Grace Tin Yun Chung Maha Hafez Ibrahim Christopher W Dawson Paul G Murray Ian C Paterson Lee Fah Yap 《The Journal of pathology》2017,242(1):62-72
Undifferentiated nasopharyngeal carcinoma (NPC) is a cancer with high metastatic potential that is consistently associated with Epstein–Barr virus (EBV) infection. In this study, we have investigated the functional contribution of sphingosine‐1‐phosphate (S1P) signalling to the pathogenesis of NPC. We show that EBV infection or ectopic expression of the EBV‐encoded latent genes (EBNA1, LMP1, and LMP2A) can up‐regulate sphingosine kinase 1 (SPHK1), the key enzyme that produces S1P, in NPC cell lines. Exogenous addition of S1P promotes the migration of NPC cells through the activation of AKT; shRNA knockdown of SPHK1 resulted in a reduction in the levels of activated AKT and inhibition of cell migration. We also show that S1P receptor 3 (S1PR3) mRNA is overexpressed in EBV‐positive NPC patient‐derived xenografts and a subset of primary NPC tissues, and that knockdown of S1PR3 suppressed the activation of AKT and the S1P‐induced migration of NPC cells. Taken together, our data point to a central role for EBV in mediating the oncogenic effects of S1P in NPC and identify S1P signalling as a potential therapeutic target in this disease. Copyright © 2017 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd. 相似文献
73.
Lin TY Kao HT Hsieh SH Huang YC Chiu CH Chou YH Yang PH Lin RI Tsao KC Hsu KH Chang LY 《The Pediatric infectious disease journal》2003,22(10):889-894
OBJECTIVES: Neonatal enterovirus infections have diverse manifestations, from asymptomatic to fatal. An understanding of the risk factors associated with severe cases might help to reduce enterovirus-related morbidity and mortality. METHODS: From July 1989 through June 1998, neonates with virus culture-confirmed nonpolio enterovirus infection at Chang Gung Children's Hospital were enrolled in the study and divided into three groups: nonspecific febrile illness; aseptic meningitis; and hepatic necrosis with coagulopathy (HNC). Demographic factors, clinical manifestations, laboratory data and outcome were analyzed to reveal factors associated with clinical severity and fatality. RESULTS: There were 146 cases including 43 neonates with nonspecific febrile illness, 61 with aseptic meningitis and 42 with HNC. By multiple logistic regression analysis, the most significant factors associated with HNC were prematurity, maternal history of illness, earlier age of onset (< or =7 days), higher white blood cell count (WBC > or =15 000/mm3) and lower hemoglobin (< or =10.7 g/dl). In 10 (24%) of 42 cases, HNC was fatal. In comparison with nonfatal cases of HNC, fatal cases had higher WBC, lower hemoglobin, higher bilirubin and higher incidence of concurrent myocarditis. Multivariate analysis showed the most significant factors associated with fatality from HNC to be total bilirubin >14.3 mg/dl (adjusted odds ratio, 29.1; 95% confidence interval, 2.5 to 355.5; P = 0.007) and concurrent myocarditis (adjusted odds ratio, 13.7; 95% confidence interval, 1.1 to 177.2; P = 0.04). Intravenous immunoglobulin did not correlate with clinical outcomes in cases with HNC. CONCLUSIONS: Prematurity, maternal history of illness, earlier age of onset, higher WBC and lower hemoglobin are significant factors associated with HNC; higher total bilirubin and concurrent myocarditis were most significantly associated with fatality from HNC. 相似文献
74.
Yung-Fu Yang Yu-Ping Tsao Chang-Shen Yin Show-Li Chen Tang-Yuan Chu 《Journal of medical virology》1996,48(4):302-307
Infection with different types of human papillomavirus (HPV) is associated with neoplasia at different anatomic sites. The “low-risk” HPVs (LR-HPV) are responsible for benign genital lesions such as condyloma acuminata. In order to clarify the tumorigenic mechanism of LR-HPV, the HPV infection status was investigated and the expression of the c-jun proto-oncogene in different HPV-related skin and genital lesions analyzed. Of the 17 condyloma specimens analyzed by Western blotting, 13 cases (76.5%) exhibited overexpression of the c-jun gene. All 13 cases harbored high copy numbers of the LR-HPV genome with an average of 926 copies per cell, whereas the other four cases had an average of 12 copies of LR-HPV per cell (P < 0.001). Further typing of HPV by Southern blotting revealed that HPV-6 and HPV-11 infections predominated in c-jun positive cases. The c-jun protein was detected much less frequently in cervical cancers (three of 29, or 10.3%) and skin warts (one of 10), and was not detected in five genital polyps or in five normal cervical tissues. These findings suggest a type 6/11-specific induction of c-jun gene expression in HPV-related neoplastic lesions. © 1996 Wiley-Liss, Inc. 相似文献
75.
Zhang H Tsao SW Jin C Strömbeck B Yuen PW Kwong YL Jin Y 《Cancer Genetics and Cytogenetics》2004,150(2):144-152
Cytogenetic and molecular cytogenetic analyses were performed on four sublines derived from a newly established, SV40T-immortalized nasopharyngeal (NP) cell line, NP69, with two of the sublines expressing LMP1, an Epstein-Barr virus–encoded gene. A total of seven cytogenetically related subclones were identified, all having highly complex karyotypes with massive numerical and structural rearrangements. Centromeric rearrangements in the form of isochromosomes and whole-arm translocations were prevalent. A cytogenetic sign of gene amplification [i.e., homogeneously staining region (HSR)] was detected at 1q25 in all metaphase cells analyzed. Multicolor combined binary ratio labeling fluorescence in situ hybridization (COBRA-FISH) was used to confirm the karyotypic interpretations. Furthermore, multicolor COBRA-FISH also showed that part of the HSR contained chromosome 20 material. Extensive clonal evolution could be observed by the assessment of karyotypic variation among different subclones and individual metaphase cells. The evaluation of clonal evolution enabled the identification of the temporal order of chromosome aberrations during cell immortalization and malignant transformation. A striking karyotypic similarity was found between sublines expressing LMP1 and an NP carcinoma cell line, with loss of genetic material from chromosome arm 3p being an important recurrent observation. More interestingly, the karyotypic features of NP69 were also similar to those of many epithelial malignancies. Our observations suggest that serial transformation of NP cell lines might provide a useful in vitro model for the study of the multistep neoplastic transformation of NP cells. 相似文献
76.
Chuen -Mao Yang Hui -Liang Tsao Chi -Tso Chiu Lir -Wan Fan Sheu -Meei Yu 《Pflügers Archiv : European journal of physiology》1996,432(4):708-716
The effects of increases in cellular adenosine 3′5′-cyclic monophosphate (cAMP) on 5-hydroxytryptamine-(5-HT-) induced generation
of inositol phosphates (IPs) and increases in intracellular Ca2+ ([Ca2+]i) were investigated using canine cultured tracheal smooth muscle cells (TSMCs). Cholera toxin and forskolin induced concentration-
and time-dependent cAMP formation with half-maximal effects (−logEC50) produced at concentrations of 7.0 ± 0.5 and 4.9 ± 0.4 respectively. Pretreatment of TSMCs with either forskolin or dibutyryl
cAMP inhibited 5-HT-stimulated responses. Even after treatment for 24h, these agents still inhibited the 5-HT-induced Ca2+ mobilization. The inhibitory effects of these agents produced both depression of the maximal response and a shift to the
right of the concentration response curves of 5-HT. The water-soluble forskolin analogue L-858051 [7-deacetyl-7β-(γ-N-methylpiperazino)-butyryl forskolin] significantly inhibited the 5-HT-stimulated accumulation of IPs. In contrast, the addition
of 1,9-dideoxy forskolin, an inactive forskolin analogue, had little effect on this response. Moreover, SQ-22536 [9-(tetrahydro-2-furanyl)-9-H-purin-6-amine], an inhibitor of adenylate cyclase, and both H-89 [N-(2-aminoethyl)-5-isoquinolinesulphonamide] and HA-1004[N-(2-guanidinoethyl)-5-isoquinolinesulphonamide], inhibitors of cAMP-dependent protein kinase (PKA), attenuated the ability
of forskolin to inhibit the 5-HT-stimulated accumulation of IPs. These results suggest that activation of cAMP/PKA was involved
in these inhibitory effects of forskolin. The AlF4
−-induced accumulation of IPs was inhibited by forskolin, suggesting that G protein(s) are directly activated by AlF4
−- and uncoupled from phospholipase C by forskolin treatment. These results suggest that activation of cAMP/PKA might inhibit
the 5-HT-stimulated phosphoinositide breakdown and consequently reduce the [Ca2+]i increase or inhibit both responses independently.
Received: 14 March 1996/Accepted: 10 April 1996 相似文献
77.
Description of the transcriptomes of immune response-activated hemocytes from the mosquito vectors Aedes aegypti and Armigeres subalbatus 总被引:3,自引:0,他引:3 下载免费PDF全文
78.
The purpose of this quasi-experimental research was to assess the effectiveness of a perimenopausal health education intervention for mid-life women in northern Taiwan. The health education intervention included a health education brochure, one-on-one teaching. One hundred seventy-nine women were in the intervention group and 174 women were in the control group. Education effectiveness was assessed by participants' scores on four questionnaires at the beginning of the study and 3 months after initial recruitment. Both groups of women were compared on changes in their scores on health knowledge, level of perceived uncertainty, health behaviors and perceived perimenopausal disturbances. The intervention group had significantly reduced scores on perimenopausal disturbances (P < 0.005) and reported increase practice of healthy behaviors (P < 0.001) compared to the control group. However, a significant decrease of perceived uncertainty was only found in the subgroup of women recruited from the Chinese medicine clinic of the control group (t = 2.22; d.f. = 58; P < 0.05). Chinese medicine physicians assess patients based on a philosophical approach that treats all symptoms holistically. This may have helped reduce patient uncertainty. 相似文献
79.
Clinical profiling of recombinant follicle stimulating hormone (rFSH; Puregon): relationship between serum FSH and efficacy 总被引:9,自引:0,他引:9
Single-dose and multiple-rising dose studies of recombinantfollicle stimulating hormone (rFSH) in hypogonadotrophic maleand female volunteers demonstrated that the rate of FSH absorptionafter i.m. injection is higher in men than in women. In theabsence of endogenous FSH, a correlation between serum FSH andbody weight became apparent. The elimination half-life of rFSHwas not different between the sexes and was comparable withurinary FSH. However, the in-vitro bio:immuno ratio of serumFSH was significantly higher after the administration of rFSHthan after urinary FSH. When rFSH was administered daily witha fixed dose, steady state levels were reached within 3-5 days.Serum FSH concentrations increased in a dose-dependent mannerwhen the daily dose was increased weekly over 3 weeks from 75to 225 IU. In hypogonadotrophic women, rFSH induced normal folliculargrowth whereas oestrogen synthesis was impaired. In women pituitarysuppressed by a high-dose oral contraceptive, the daily administrationof 150 IU rFSH for 1 week induced more and larger antral folliclesthan the same regimen with urinary FSH, whereas the serum immunoactiveFSH concentrations measured 24 h after each dosing were similar.It is concluded that even though equal or lower serum immunoactiveFSH concentrations were obtained following the administrationof rFSH compared with urinary FSH, circulating bioactivity FSHconcentrations were higher. Therefore, the conventional ideathat serum immunoreactive FSH correlates positively with themagnitude of the ovarian response should be reconsidered. 相似文献
80.
Halfon P Pérusat S Bourlière M Bronowicki JP Trimoulet P Benhamou Y Leroy V Marcellin P Foucher J Penaranda G Chêne G Couzigou P;ANRS HC GAMMATRI Study Group 《Journal of medical virology》2010,82(12):2027-2031
A lack of antiviral response in patients with chronic hepatitis C treated with pegylated (PEG)‐interferon (IFN)‐α‐2a + ribavirin (RIBA) may be explained by neutralizing antibodies to IFN‐α‐2a. The aim of this study was to assess neutralizing antibodies to IFN‐α‐2a and IFN levels in non‐responder patients who were re‐treated by PEG IFN‐α‐2a and RIBA for 12 weeks. Non‐responders to a first‐line treatment of PEG IFN‐α‐2a + RIBA were included for treatment with PEG IFN‐α‐2a (180 µg/week) + RIBA (1,000 mg/day if <75 kg, 1,200 mg otherwise) for 48 weeks. HCV RNA was measured at week 12. IFN levels and neutralizing antibodies to IFN‐α‐2a were measured retrospectively on stored sera at baseline and weeks 4 and 12, using a quantitative sandwich ELISA for neutralizing antibodies to IFN‐α‐2a. Twenty‐three patients were non‐responders and 19 patients were responders at week 12 of the initial phase of the second‐line treatment. Non‐responders and responders did not differ statistically: baseline age (median age 47 vs. 50 years), HCV RNA (median 6.8 vs. 6.4 log10 copies/ml), gender (70% vs. 73% males), genotype (genotype 1: 91% vs. 80%). The median IFN‐α‐2a levels (pg/ml) at weeks 0, 4, and 12 (interquartile range) did not differ between the 19 responders to initial phase of second‐line treatment and the 23 non‐responders: <3.3 (<3.3–371.4), 1457.3 (106.8–3284.8), and 1,652 (90.8–5,000); 84.5 (3.3–277.4), 1407.4 (120.2–2443.4), and 1620.1 (120.2–2287.1), respectively. Among non‐selected consecutive non‐responder patients, re‐treatment with PEG IFN‐α‐2a + RIBA is associated with virological response regardless of the presence of antibody‐mediated resistance to conventional IFN treatment. J. Med. Virol. 82:2027–2031, 2010. © 2010 Wiley‐Liss, Inc. 相似文献