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1.
Lupus ; 28(1): 19-26, 2019 Jan.
Article in English | MEDLINE | ID: mdl-30458691

ABSTRACT

OBJECTIVE: The objective of this paper is to investigate the incidence rate, risk factors and outcome of osteomyelitis among patients with systemic lupus erythematosus (SLE). MATERIALS AND METHODS: We conducted a cohort study using data for patients enrolled in the Taiwan National Health Insurance Database from 2000 to 2012. Patients with SLE and age- and sex-matched controls without SLE were enrolled. Primary endpoint was the first occurrence of osteomyelitis. Risks of osteomyelitis in SLE patients were analyzed with Cox proportional hazards regression models, including age, sex, comorbidities and medications. RESULTS: Among 24,705 SLE patients (88.4% women, mean age 35.8 years) with a median follow-up of 9.1 years, 386 patients had osteomyelitis. The incidence rate ratio (IRR) of osteomyelitis in the SLE group vs the control group was 8.52 (95% confidence interval (CI) 7.24-10.05). The SLE group had higher incidence rates of osteomyelitis than the control group, especially in pediatric subgroups (IRR 41.1 95% CI 18.57-107.35). Compared to controls, SLE patients experienced osteomyelitis at a younger age (42.3 vs 58.1 years) but did not have an increased risk of mortality (hazard ratio 0.7; 95% CI 0.21-2.38). Age >60 years, male gender, malignancy within five years, prior bone fracture and higher daily prednisolone dose (>7.5 mg) cumulatively for >180 days increased risk for osteomyelitis. CONCLUSIONS: SLE patients have a higher IRR of osteomyelitis than controls. Pediatric and elder SLE patients, patients with a history of bone fracture, malignancy within five years and higher-dose glucocorticoid use have a higher risk of osteomyelitis and should be carefully monitored.


Subject(s)
Lupus Erythematosus, Systemic/complications , Osteomyelitis/epidemiology , Adolescent , Adult , Age Distribution , Aged , Case-Control Studies , Databases, Factual , Female , Humans , Incidence , Lupus Erythematosus, Systemic/mortality , Male , Middle Aged , Multivariate Analysis , Retrospective Studies , Risk Assessment , Risk Factors , Sex Distribution , Survival Analysis , Taiwan/epidemiology , Young Adult
2.
Br J Cancer ; 112(2): 391-402, 2015 Jan 20.
Article in English | MEDLINE | ID: mdl-25461807

ABSTRACT

BACKGROUND: We showed previously that breast carcinoma amplified sequence 2 (BCAS2) functions as a negative regulator of p53. We also found that BCAS2 is a potential AR-associated protein. AR is essential for the growth and survival of prostate carcinoma. Therefore we characterised the correlation between BCAS2 and AR. METHODS: Protein interactions were examined by GST pull-down assay and co-immunoprecipitation. Clinical prostate cancer (PCa) specimens were evaluated by immunohistochemical assay. AR transcriptional activity and LNCaP cell growth were assessed by luciferase assay and MTT assay, respectively. RESULTS: BCAS2 expression was significantly increased in PCa. BCAS2 stabilised AR protein through both hormone-dependent and -independent manners. There are at least two mechanisms for BCAS2-mediated AR protein upregulation: One is p53-dependent. The p53 is suppressed by BCAS2 that results in increasing AR mRNA and protein expression. The other is via p53-independent inhibition of proteasome degradation. As BCAS2 can form a complex with AR and HSP90, it may function with HSP90 to stabilise AR protein from being degraded by proteasome. CONCLUSIONS: In this study, we show that BCAS2 is a novel AR-interacting protein and characterise the correlation between BCAS2 and PCa. Thus we propose that BCAS2 could be a diagnostic marker and therapeutic target for PCa.


Subject(s)
Neoplasm Proteins/physiology , Prostatic Neoplasms/metabolism , Receptors, Androgen/genetics , Transcription, Genetic , Benzoquinones/pharmacology , Cell Line, Tumor , Cell Proliferation , Gene Expression Regulation, Neoplastic , HEK293 Cells , HSP90 Heat-Shock Proteins/antagonists & inhibitors , Half-Life , Humans , Inhibitory Concentration 50 , Lactams, Macrocyclic/pharmacology , Male , Neoplasm Grading , Prostatic Neoplasms/pathology , Proteasome Endopeptidase Complex/metabolism , Protein Stability , Proteolysis , Receptors, Androgen/metabolism , Tumor Suppressor Protein p53/metabolism
3.
Osteoporos Int ; 26(2): 601-10, 2015 Feb.
Article in English | MEDLINE | ID: mdl-25270396

ABSTRACT

SUMMARY: In patients with systemic lupus erythematosus (SLE), low bone mineral density (BMD) is associated with increased age, prolonged disease, low body mass index (BMI), and overlap with rheumatoid arthritis (RA). Elevated fibroblast growth factor (FGF)-23 in cyclosporine A (CsA) users with SLE are associated with decreased active vitamin D and osteocalcin. INTRODUCTION: The objective of this study was to investigate the steroid and CsA effect on bone metabolism and serum FGF-23 in SLE patients. METHODS: Seventy-two SLE patients and 10 age- and sex-matched healthy individuals underwent blood tests for bone metabolic biomarkers and FGF-23, and lumbar spine dual-energy X-ray absorptiometry for BMD. RESULTS: Comparisons between patients and controls were made in premenopausal women/men younger than 50 years and postmenopausal women/men older than 50 years separately. SLE patients had more frequent low Z-score (≤-2.0, 8.5 vs. 0%), osteopenia (-2.5

Subject(s)
Bone Remodeling/physiology , Cyclosporine/therapeutic use , Fibroblast Growth Factors/blood , Glucocorticoids/therapeutic use , Immunosuppressive Agents/therapeutic use , Lupus Erythematosus, Systemic/drug therapy , Absorptiometry, Photon , Adult , Biomarkers/blood , Bone Diseases, Metabolic/complications , Bone Remodeling/drug effects , Case-Control Studies , Cross-Sectional Studies , Cyclosporine/pharmacology , Female , Fibroblast Growth Factor-23 , Fibroblast Growth Factors/drug effects , Glucocorticoids/pharmacology , Humans , Immunosuppressive Agents/pharmacology , Lumbar Vertebrae/diagnostic imaging , Lupus Erythematosus, Systemic/complications , Male , Middle Aged , Osteoporosis/complications , Premenopause , Treatment Outcome
4.
Lupus ; 23(14): 1528-32, 2014 Dec.
Article in English | MEDLINE | ID: mdl-25145338

ABSTRACT

When the disease activity of systemic lupus erythematosus (SLE) is controlled appropriately, a pregnant woman who has lupus is able to carry safely to term and deliver a healthy infant. While the physiology of a healthy pregnancy itself influences ventilatory function, acute pulmonary distress may decrease oxygenation and influence both mother and fetus. Though respiratory failure in pregnancy is relatively rare, it remains one of the leading conditions requiring intensive care unit admission in pregnancy and carries a high risk of maternal and fetal morbidity and mortality, not to mention the complexity caused by lupus flare. We report a case of SLE complicated with lupus pneumonitis and followed by acute respiratory distress during pregnancy. Though there is a high risk of maternal and fetal morbidity and mortality, maternal respiratory function improved after cesarean section and treatment of the underlying causes. The newborn had an extremely low birth weight but was well at discharge.


Subject(s)
Lupus Erythematosus, Systemic/complications , Pregnancy Complications/etiology , Respiratory Distress Syndrome/etiology , Adult , Anti-Bacterial Agents/therapeutic use , Cesarean Section , Female , Humans , Immunoglobulins, Intravenous/therapeutic use , Immunologic Factors/therapeutic use , Infant, Extremely Low Birth Weight , Lupus Erythematosus, Systemic/therapy , Plasmapheresis , Pregnancy , Pregnancy Complications/therapy , Respiratory Distress Syndrome/therapy , Steroids/therapeutic use
5.
Cardiovasc Res ; 76(2): 213-23, 2007 Nov 01.
Article in English | MEDLINE | ID: mdl-17651710

ABSTRACT

OBJECTIVE: Pigment epithelial-derived factor (PEDF) is a potent anti-angiogenic factor whose effects are partially mediated through the induction of endothelial cell apoptosis. The pathway mediating endothelial cell apoptosis has not been fully established. Here we investigated the participation of peroxisome proliferator-activated receptor gamma (PPARgamma) and p53 in the apoptosis of human umbilical vein endothelial cells (HUVECs). METHODS AND RESULTS: HUVECs pretreated with either PPARgamma antagonist or PPARgamma small interfering RNA (siRNA) suppressed PEDF-induced apoptosis as determined by TUNEL assay, annexin V-FITC/PI staining, and cleavage of procaspase-8, -9, -3. PEDF sequentially induced PPARgamma and p53 expression as observed in immunoblotting and immunofluoresence assays. PEDF also increased the transcriptional activity of PPARgamma as evident from electromobility shift assays, and p53 as determined by the phosphorylation and acetylation of p53 and the induction of Bax. The induction of p53 by PEDF was abolished by either PPARgamma antagonist or PPARgamma siRNA. PEDF-mediated HUVEC apoptosis and cleavage of procaspases were significantly attenuated by p53 siRNA. CONCLUSIONS: Our observations indicate that PEDF induces HUVECs apoptosis through the sequential induction of PPARgamma and p53 overexpression. With the growing interest in anti-angiogenesis as a novel approach to cancer therapy, defining the mechanism of PEDF-mediated HUVEC apoptosis may facilitate the development of new therapeutics.


Subject(s)
Apoptosis , Endothelial Cells/physiology , Eye Proteins/physiology , Nerve Growth Factors/physiology , PPAR gamma/physiology , Serpins/physiology , Signal Transduction/physiology , Tumor Suppressor Protein p53/physiology , Caspases/physiology , Cells, Cultured , Humans , Transcription, Genetic , Umbilical Veins/cytology
6.
Int J Gynecol Cancer ; 17(2): 418-25, 2007.
Article in English | MEDLINE | ID: mdl-17316361

ABSTRACT

Peroxisome proliferator-activated receptor gamma (PPARgamma) is a member of the nuclear hormone receptor superfamily of ligand-activated transcription factors. PPARgamma agonists inhibit the growth of many types of cancers. To our knowledge, the effect of PPARgamma agonist on ovarian tumors is not reported. In this study, we used two human ovarian carcinoma cell lines (ES-2 and PA-1) to examine the effects of the PPARgamma agonists troglitazone (TGZ) and ciglitazone (CGZ) on cell survival. CGZ and TGZ inhibited viability in a dose-dependent manner in both types of ovarian cancer cells. The agonists also decreased cellular proliferation in association with an increase in the number of cells arrested in the G0/G1 phase of the cell cycle. Moreover, they increased apoptosis while increasing caspase-3 activity. Incubation of both the cell lines with the PPARgamma agonists led to upregulated PPARgamma expression. This effect appeared to be PPARgamma independent because the PPARgamma antagonist GW9662 did not reverse it. Along with the induction of apoptosis in ovarian cancer cells, protein expression levels of p53 and Bax markedly increased in response to the PPARgamma agonists. Our results demonstrated that PPARgamma agonists inhibited the viability of human ovarian cancer cells, at least partly by inducing apoptosis. As a result, these agonists may serve as future drugs for the prevention and treatment of ovarian cancer.


Subject(s)
Apoptosis/drug effects , Carcinoma/pathology , Cell Cycle/drug effects , Ovarian Neoplasms/pathology , PPAR gamma/agonists , Carcinoma/metabolism , Caspase 3/metabolism , Cell Line, Tumor , Cell Proliferation/drug effects , Cell Survival/drug effects , Chromans/pharmacology , Female , Humans , Ovarian Neoplasms/metabolism , PPAR gamma/metabolism , Proto-Oncogene Proteins c-bcl-2/metabolism , Thiazolidinediones/pharmacology , Troglitazone , Tumor Suppressor Protein p53/metabolism , bcl-2-Associated X Protein/metabolism
7.
Oncogene ; 26(1): 42-53, 2007 Jan 04.
Article in English | MEDLINE | ID: mdl-16819515

ABSTRACT

Human papillomavirus type 16 E5 (HPV-16 E5) is a highly hydrophobic membrane protein with weak-transforming activity, which is associated with ErbB4 receptor in HPV-16-infected cervical lesions. Presently, we investigated the transforming mechanisms of E5 involving ErbB4 signaling. Firstly, we report a role for ErbB4 (JM-b/CYT-1) receptor that activates c-jun gene expression and phosphorylating at Ser63 and Ser73 of the c-Jun protein in ligand-independent and Ras-c-jun NH(2)-terminal kinase-dependent pathway. Secondly, we show that HPV-16 E5 protein can form a complex with ErbB4 via binding to the extracellular and transmembrane domains of ErbB4 (JM-b/CYT-1). When co-expressing HPV-16 E5 and ErbB4 in cells, E5 can abrogate ErbB4-induced c-Jun protein expression and phosphorylation resulted in increasing cell proliferation compared to ErbB4-expressing cells. The interaction between of HPV-16 E5 and ErbB4 provides more insight into the mechanisms of HPV-16 E5 transformation induction.


Subject(s)
ErbB Receptors/physiology , Oncogene Proteins, Viral/physiology , Proto-Oncogene Proteins c-jun/metabolism , Base Sequence , Blotting, Western , Cell Line , DNA Primers , Humans , Microscopy, Fluorescence , Phosphorylation , Proto-Oncogene Proteins c-jun/chemistry , Receptor, ErbB-4 , Reverse Transcriptase Polymerase Chain Reaction , Serine/metabolism
8.
Apoptosis ; 11(11): 1899-908, 2006 Nov.
Article in English | MEDLINE | ID: mdl-16927023

ABSTRACT

Retinal pigment epithelial (RPE) cells are constantly exposed to oxidative injury while clearing byproducts of photoreceptor turnover, a circumstance thought to be responsible for degenerative retinal diseases. The mechanisms of hydrogen peroxide (H(2)O(2))-induced apoptosis in RPE cells are not fully understood. We studied signal transduction mechanisms of H(2)O(2)-induced apoptosis in the human RPE cell line ARPE-19. Activation of two stress kinases (JNK and p38) occurs during H(2)O(2) stimulation, and H(2)O(2)-mediated cell death was significantly reduced by their specific inhibition. Exposure to a lethal dose of H(2)O(2) elicited Bax translocation to the mitochondria and release of apoptosis-inducing factor (AIF) from the mitochondria, both of which were abolished by either JNK- or p38-specific inhibitors. Both H(2)O(2)-induced cell death and JNK/p38 phosphorylation were partially inhibited by C. difficile toxin B, inhibitor of Rho, Rac, and cdc42. Use of pull-down assays revealed that the small GTPase activated by H(2)O(2) is Rac1. This study is the first to demonstrate that H(2)O(2) induces a Rac1/JNK1/p38 signaling cascade, and that JNK and p38 activation is important for H(2)O(2)-induced apoptosis as well as AIF/Bax translocation of RPE cells.


Subject(s)
Apoptosis , Hydrogen Peroxide/pharmacology , Mitogen-Activated Protein Kinase 8/metabolism , Pigment Epithelium of Eye/cytology , p38 Mitogen-Activated Protein Kinases/metabolism , Active Transport, Cell Nucleus , Anthracenes/pharmacology , Apoptosis/drug effects , Apoptosis Regulatory Proteins/metabolism , Bacterial Proteins/pharmacology , Bacterial Toxins/pharmacology , Cell Line, Tumor , Cell Nucleus/metabolism , Enzyme Inhibitors/pharmacology , Humans , Imidazoles/pharmacology , MAP Kinase Signaling System , Mitogen-Activated Protein Kinase 8/antagonists & inhibitors , Protein Transport , Pyridines/pharmacology , p38 Mitogen-Activated Protein Kinases/antagonists & inhibitors , rac1 GTP-Binding Protein/antagonists & inhibitors
10.
Arch Virol ; 149(1): 1-15, 2004 Jan.
Article in English | MEDLINE | ID: mdl-14689272

ABSTRACT

Vectors derived from the adeno-associated viruses (AAV) have been successfully used for the long-term expression of therapeutic genes in animal models and in patients. Stable expression of the transgene in the transduced cells can be used to correct disease stemming from genetic deficiencies. One of the major advantages of these vectors is reported to be the absence of deleterious immune responses following gene transfer. However, recent studies have shown that AAV vectors elicit humoral and cellular responses against the transgene products. This review article will focus on these two unique yet converse aspects of AAV: the ability to elicit host immune response to destroy target cells containing the transduced protein and the ability to evade immune response leading to stable expression of the transduced genes.


Subject(s)
Dependovirus/genetics , Genetic Vectors , Transgenes/immunology , Dendritic Cells/virology , Gene Expression , Immune Tolerance , Transduction, Genetic
11.
Gene Ther ; 9(1): 2-11, 2002 Jan.
Article in English | MEDLINE | ID: mdl-11850717

ABSTRACT

We have utilized a recombinant adeno-associated viral (AAV) vector carrying the angiostatin gene as an anti-angiogenesis strategy to treat the malignant brain tumor in a C6 glioma/Wistar rat model. Angiostatin, as a potent angiogenesis inhibitor, shows high promises as an anti-cancer drug through the inhibition of tumor neovessel formation. However, sustained in vivo protein delivery is required to achieve the therapeutic effects. The AAV vector has been proven to be able to deliver sustained and high-level gene expression in vivo, and therefore, is well suited to such a purpose. In this study, we implanted 5 x 10(5) C6 glioma cells into the rat brain 7 days before gene therapy. Intratumoral injection of a high-titer AAV-angiostatin vector has rendered efficacious tumor suppression and resulted in long-term survival in 40% of the treated rats, whereas the control AAV-GFP vector did not have any therapeutic benefits. In addition, we have investigated the combined gene therapy of an adenoviral vector carrying the suicidal thymidine kinase gene along with the AAV-angiostatin vector. The combined therapy offered the best tumor-suppressive effects and increased long-term survival to 55% in the treated rats. Our study has demonstrated the potential of using AAV as a safe and effective vector for anti-angiogenic gene therapy of brain tumors.


Subject(s)
Angiogenesis Inhibitors/therapeutic use , Brain Neoplasms/therapy , Genetic Therapy/methods , Glioma/therapy , Peptide Fragments/therapeutic use , Plasminogen/therapeutic use , Adenoviridae/genetics , Angiogenesis Inhibitors/genetics , Angiostatins , Animals , Gene Expression , Genetic Vectors/administration & dosage , Injections, Intralesional , Male , Models, Animal , Neoplasm Transplantation , Peptide Fragments/genetics , Plasminogen/genetics , Rats , Rats, Wistar , Simplexvirus/enzymology , Thymidine Kinase/genetics , Transfection , Tumor Cells, Cultured
13.
Invest Ophthalmol Vis Sci ; 42(10): 2401-7, 2001 Sep.
Article in English | MEDLINE | ID: mdl-11527956

ABSTRACT

PURPOSE: To test the efficacy of a recombinant adeno-associated virus (rAAV) vector that expresses mouse angiostatin in suppressing experimental choroidal neovascularization (CNV) in a rat model. METHODS: An rAAV vector, rAAV-angiostatin, was constructed to deliver the mouse angiostatin gene. rAAV-angiostatin and a control virus, rAAV-lacZ, were delivered in vivo by subretinal injection in Brown Norway rats, and the delivery was confirmed by reverse-transcriptase polymerase chain reaction (RT-PCR). For a CNV suppression experiment, CNV was generated by fundus krypton laser photocoagulation 7 days after the viral vector injection and was evaluated by fluorescein angiography (FA) and histology. Apoptosis in retina was analyzed using the TUNEL assay. Inflammation in the retina was investigated by immunohistochemistry, using antibodies that recognize lymphocytes. RESULTS: rAAV-angiostatin injection led to sustained expression of the angiostatin gene in chorioretinal tissue for up to150 days. FA analysis revealed significant reduction of the average sizes of CNV lesions in rAAV-angiostatin-injected eyes when compared with rAAV-lacZ-injected eyes at both 14 (P = 0.019) and 150 (P = 0.010) days after injection. Moreover, histologic analysis of CNV lesions also revealed significantly smaller lesions in rAAV-angiostatin-injected eyes (P = 0.004). As for adverse effects, rAAV-angiostatin injection did not cause inflammation or apoptosis of cells in retina and choroid. CONCLUSIONS: This is the first report that subretinal injection of rAAV-angiostatin can significantly reduce the sizes of CNV lesions. This and the absence of apoptosis and inflammation in chorioretinal tissue indicate the feasibility of a gene therapy approach for treatment of CNV disease.


Subject(s)
Choroidal Neovascularization/therapy , Dependovirus/genetics , Genetic Therapy , Peptide Fragments/genetics , Plasminogen/genetics , Angiostatins , Animals , Apoptosis , Choroidal Neovascularization/metabolism , Choroidal Neovascularization/pathology , Dependovirus/metabolism , Fluorescein Angiography , Gene Expression , Genetic Vectors , Humans , Immunoenzyme Techniques , In Situ Nick-End Labeling , Injections , Peptide Fragments/metabolism , Plasminogen/metabolism , Rats , Rats, Inbred BN , Retina/pathology , Reverse Transcriptase Polymerase Chain Reaction , Transfection
14.
J Biomed Sci ; 8(2): 206-13, 2001.
Article in English | MEDLINE | ID: mdl-11287752

ABSTRACT

To investigate the expression of human papillomavirus type 16 (HPV-16) E5 protein in squamous neoplastic changes in the uterine cervix, the specific E5 antibody was generated and used to identify the expression of E5 protein in 40 cases of HPV-16-positive tissues and 5 previously identified HPV-negative normal cervical tissues. The results revealed that E5 protein was primarily expressed in the lower third of the epithelium in low-grade squamous intraepithelial lesions (SILs) and throughout the whole epithelium in high-grade SILs. In invasive squamous carcinoma, 60% of HPV-16-infected cancers which contained the episomal viral genome had the E5 gene, and could express E5 protein which was located throughout the whole epithelium. Previously, we documented the expression of type I growth factor receptors [ERBB1/EGFR (epidermal growth factor receptor), ERBB2, ERBB3 and ERBB4] in the full range of cervical neoplasias by immunohistochemistry assay. Hence, in this study, we extensively analyzed the correlation between the expression of E5 protein and the expression of type I growth factor receptors. Among 40 HPV-16- infected cervical neoplasias, we found that the expression of E5 protein was significantly correlated with either the expression of the ERBB1 or the ERBB4 receptor.


Subject(s)
Carcinoma, Squamous Cell/metabolism , Oncogene Proteins, Viral/metabolism , Uterine Neoplasms/metabolism , Animals , Antibodies/immunology , Antibody Specificity , Cell Line, Transformed , ErbB Receptors/metabolism , Female , Fluorescent Antibody Technique , Humans , Immunohistochemistry , Mice , Oncogene Proteins, Viral/immunology , Receptor, ErbB-2/metabolism , Receptor, ErbB-3/metabolism
15.
Chang Gung Med J ; 24(10): 621-7, 2001 Oct.
Article in English | MEDLINE | ID: mdl-11771184

ABSTRACT

BACKGROUND: Cornea endothelial cells are nondividing cells containing pumping function which is crucial for cornea clarity and integrity. Endothelial cell loss occurs after cataract surgical procedures such as phacoemulsification. The authors hypothesize that endothelium damage occurs through apoptosis. METHODS: Ultrasound was achieved by placing a phacoemulsification probe in the anterior chamber and delivering 0% or 50% of maximum power for 2.5 min. The corneal tissue was harvested immediately, and at 1 and 7 days after the operation. Corneal tissue was stained by hemotoxylin and eosin (H&E) and evaluated by light microscopy. Endothelium apoptosis was monitored using the terminal deoxynucleotidyl transferase-mediated dUTP-digoxigenin nick-end labeling (TUNEL) assay to detect DNA fragmentation. RESULTS: In corneas which underwent phacoemulsification with 0% energy, no cell loss or apoptosis was identified immediately, 1 or 7 days after the operation. Likewise, in corneas exposed to 50% energy, no cell loss or apoptosis was detected immediately after phacoemulsification. However, minimal amount of cell loss but prominent apoptosis was detected with the TUNEL assay 1 day after the operation, whereas significant cell loss but no apoptosis was detected 7 days after the operation by H&E stain. CONCLUSIONS: These results demonstrate that corneal endothelial cell loss induced by ultrasound damage occurs through apoptosis.


Subject(s)
Apoptosis , Endothelium, Corneal/pathology , Phacoemulsification/adverse effects , Animals , DNA Fragmentation , In Situ Nick-End Labeling , Male , Rabbits
16.
J Biomol NMR ; 21(3): 209-20, 2001 Nov.
Article in English | MEDLINE | ID: mdl-11775738

ABSTRACT

The solution structure and hydration of a DNA.RNA hybrid chimeric duplex [d(CGC)r(amamam)d(TTTGCG)]2 in which the RNA adenines were substituted by 2'-O-methylated riboadenines was determined using two-dimensional NMR, simulated annealing, and restrained molecular dynamics. Only DNA residue 7T in the 2'-OMe-RNA.DNA junction adopted an O4'-endo sugar conformation, while the other DNA residues including 3C in the DNA.2'-OMe-RNA junction, adopted C1'-exo or C2'-endo conformations. The observed NOE intensity of 2'-O-methyl group to H1' proton of 4am at the DNA.2'-OMe-RNA junction is much weaker than those of 5am and 6am. The 2'-O-methyl group of 4am was found to orient towards the minor groove in the trans domain while the 2'-O-methyl groups of 5am and 6am were found to be in the gauche (+) domain. In contrast to the long-lived water molecules found close to the RNA adenine H2 and H1' protons and the methyl group of 7T in the RNA-DNA junction of [d(CGC)r(aaa)d(TTTGCG)]2, there were no long-lived water molecules found in [d(CGC)r(amamam)d(TTTGCG)]2. This is probably due to the hydrophobic enviroment created by the 2'-O-methylated riboadenines in the minor groove or due to the wider minor groove width in the middle of the structure. In addition, the 2'-O-methylation of riboadenines in pure chimeric duplex increses its melting temperature from 48.5 degrees C to 51.9 degrees C. The characteristic structural features and hydration patterns of this chimeric duplex provide a molecular basis for further therapeutic applications of DNA.RNA hybrid and chimeric duplexes with 2'-modified RNA residues.


Subject(s)
Magnetic Resonance Spectroscopy , Nucleic Acid Conformation , Nucleic Acids/chemistry , Base Sequence , DNA Methylation , Models, Molecular , Nucleic Acids/genetics , Nucleic Acids/metabolism , Protons , Solutions/chemistry , Solutions/metabolism , Temperature , Water/metabolism
17.
Exp Neurol ; 166(2): 266-75, 2000 Dec.
Article in English | MEDLINE | ID: mdl-11085892

ABSTRACT

To explore the potential of using the recombinant adeno-associated viral (rAAV) vector, expressing glial cell line-derived neurotrophic factor (GDNF) as the gene therapy for stroke, we injected rAAV vectors expressing GDNF (rAAV-GDNF) into the cortex of rats which had been experiencing transient bilateral common carotid artery ligation and right middle cerebral artery ligation for 90 min. GDNF levels in cortical tissues of rAAV-GDNF-injected animals were significantly higher than in the control animals injected with rAAV-expressing lacZ (rAAV-lacZ), indicating that rAAV can deliver and express the GDNF gene in cortical tissues. Triphenyltetrazolium chloride tissue stain analysis revealed that the rAAV-delivered GDNF gene could rescue the brain tissues from ischemia-induced injury. Cortical tissues which received rAAV-GDNF injections had both significantly smaller total volumes of infarction and smaller areas of infarction on each brain slice than those which were injected with rAAV-lacZ. An in situ labeling analysis demonstrated significantly less apoptotic cells in cortical tissues rescued by rAAV-GDNF, indicating prevention of apoptosis as the mechanism of cortical cell protection. Moreover, immunohistochemistry staining of Neu-N indicated that the rescued brain tissues contained the same number of Neu-N-positive neuronal cells as contralateral undamaged brain tissues. This provides strong evidence that cortical neuronal cells can be rescued by GDNF gene therapy. Indeed, these findings show that the rAAV is a potential delivery vector of GDNF gene for the therapy of stroke.


Subject(s)
Adenoviridae/genetics , Brain Ischemia/therapy , Genetic Therapy/methods , Genetic Vectors , Nerve Growth Factors , Nerve Tissue Proteins/genetics , Neuroprotective Agents/metabolism , Animals , Apoptosis , Brain Ischemia/pathology , Cells, Cultured , Cerebral Cortex/pathology , DNA, Complementary , Glial Cell Line-Derived Neurotrophic Factor , Humans , In Situ Nick-End Labeling , Kidney/cytology , Lac Operon , Male , Microinjections , Neurons/pathology , Rats , Rats, Sprague-Dawley , Recombinant Proteins/genetics , Stroke/pathology , Stroke/therapy
18.
J Virol ; 74(19): 9083-9, 2000 Oct.
Article in English | MEDLINE | ID: mdl-10982354

ABSTRACT

The potential of the E5 protein as a tumor vaccine candidate has not been explored yet. In this study, we evaluate the human papillomavirus type 16 (HPV-16) E5 protein delivered by an adenovirus vector as a tumor vaccine for cervical lesions. The results demonstrate that a single intramuscular injection of a recombinant adenovirus carrying the HPV-16 E5 gene into syngeneic animals can reduce the growth of tumors which contain E5 gene expression. Moreover, the E5 vaccine-induced tumor protection occurs through CD8 T cells but not through CD4 T cells in in vitro assays. In addition, our studies using knockout mice with distinct T-cell deficiencies confirm that cytotoxic T-lymphocyte-induced tumor protection is CD8 dependent but CD4 independent. Hence, HPV-16 E5 can be regarded as a tumor rejection antigen.


Subject(s)
CD8-Positive T-Lymphocytes/immunology , Cancer Vaccines , Cytotoxicity, Immunologic , Neoplasms, Experimental/immunology , Oncogene Proteins, Viral/immunology , Uterine Cervical Neoplasms/immunology , Adenoviridae , Animals , Female , Genetic Vectors , Humans , Lymphocyte Activation , Mice , Mice, Inbred C57BL , Oncogene Proteins, Viral/genetics , Vaccines, Synthetic
19.
Biochem J ; 348 Pt 2: 473-9, 2000 Jun 01.
Article in English | MEDLINE | ID: mdl-10816444

ABSTRACT

The role of Bcl-2 as an anti-apoptotic protein has been well documented. In the present work, we present evidence that Bcl-2 may also be involved in cell growth regulation. SC-M1 is an unique cell line which responds to retinoic acid (RA) treatment with reversible growth arrest [Shyu, Jiang, Huang, Chang, Wu, Roffler and Yeh (1995) Eur. J. Cancer 31, 237-243]. In this study, when treated with RA, SC-M1/Bcl2 cells, which were generated by transfecting SC-M1 cells with bcl-2 DNA, were growth-arrested two days earlier than SC-M1/neo cells, which were generated by transfecting SC-M1 cells with vector DNA. This indicates that Bcl-2 accelerates RA-induced growth arrest. In addition to the accelerated growth arrest, RA-treated SC-M1/Bcl2 cells also recovered from growth arrest two days faster than SC-M1/neo cells after the removal of RA. Previously, we had identified the cyclin-dependent kinase inhibitor p21((WAF1/CIP1)) (p21) as a mediator of RA-induced growth arrest [Tsao, Li, Kuo, Liu and Chen (1996) Biochem. J. 317, 707-711]. In a search for the mechanism by which Bcl-2 affects growth regulation, we found that p21 gene expression was more prominent in SC-M1/Bcl2 cells than in SC-M1/neo cells in the presence of RA, but when RA was removed, p21 gene expression levels in SC-M1/Bcl2 cells were also reduced earlier than in SC-M1/neo cells. The present report is the first to show that Bcl-2 accelerates not only growth arrest but also recovery from growth arrest. Moreover, the close correlation between the effect of Bcl-2 on both RA-induced growth arrest and RA-induced p21 gene expression suggests the possibility that Bcl-2 affects cell growth through the mechanism of p21.


Subject(s)
Cell Division/physiology , Proto-Oncogene Proteins c-bcl-2/metabolism , Tretinoin/pharmacology , Cell Cycle/drug effects , Cell Division/drug effects , Cyclin-Dependent Kinase Inhibitor p21 , Cyclins/metabolism , DNA, Neoplasm/metabolism , Enzyme Inhibitors/metabolism , Flow Cytometry , Genes, bcl-2 , Humans , Kinetics , Recombinant Proteins/metabolism , Stomach Neoplasms , Transfection , Tumor Cells, Cultured
20.
Biochem Biophys Res Commun ; 270(1): 303-10, 2000 Apr 02.
Article in English | MEDLINE | ID: mdl-10733944

ABSTRACT

Previously, we found that c-jun represses the tumor suppressor p21((Waf1/Cip1/Sdi1)) (p21) gene expression. In this study, we further investigated the mechanism of the inhibitory effect of c-jun on p21. After analysis of a series of deletion and point mutants of p21 promoter, we found that Sp1-3 site (-77 and -83) relative to the transcription start site played an important role for c-jun-repressing-responsive element in the p21 promoter. Both Sp1 and Sp3 transcription factors were the key factors for this event. However, the data from electrophoretic mobility shift assay indicated that c-jun did not change the Sp1 DNA-binding affinity, suggesting that additional factors may be involved in the repression of p21 by c-jun. Furthermore, c-jun could inhibit butyrate-inducing p21 gene expression through Sp1, indicating at least one common pathway whereby p21 expression is affected by c-jun and butyrate in opposing actions. Moreover, the hyperphosphorylated retinoblastoma protein (Rb) increased in c-jun expressing cells, indicating that phosphorylated Rb may play a role in regulating Sp1 to repress p21 expression. This is the first demonstration of how housekeeping factors and oncogene product counteract the function of tumor suppressor genes to control cell cycle progression.


Subject(s)
Cyclins/genetics , Genes, Tumor Suppressor , Genes, jun , Sp1 Transcription Factor/metabolism , Binding Sites , Butyrates/pharmacology , Cell Cycle/genetics , Cyclin-Dependent Kinase Inhibitor p21 , DNA-Binding Proteins/metabolism , Gene Expression Regulation , Genes, Reporter , Mutagenesis , Phosphorylation , Promoter Regions, Genetic , Protein Binding , Retinoblastoma Protein/metabolism , Sequence Deletion , Sp3 Transcription Factor , Transcription Factors/metabolism
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