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1.
Sci Data ; 11(1): 244, 2024 Feb 27.
Article in English | MEDLINE | ID: mdl-38413596

ABSTRACT

Infectious disease outbreaks transcend the medical and public health realms, triggering widespread panic and impeding socio-economic development. Considering that self-limiting diarrhoea of sporadic cases is usually underreported, the Salmonella outbreak (SO) study offers a unique opportunity for source tracing, spatiotemporal correlation, and outbreak prediction. To summarize the pattern of SO and estimate observational epidemiological indicators, 1,134 qualitative reports screened from 1949 to 2023 were included in the systematic review dataset, which contained a 506-study meta-analysis dataset. In addition to the dataset comprising over 50 columns with a total of 46,494 entries eligible for inclusion in systematic reviews or input into prediction models, we also provide initial literature collection datasets and datasets containing socio-economic and climate information for relevant regions. This study has a broad impact on advancing knowledge regarding epidemic trends and prevention priorities in diverse salmonellosis outbreaks and guiding rational policy-making or predictive modeling to mitigate the infringement upon the right to life imposed by significant epidemics.


Subject(s)
Disease Outbreaks , Salmonella Food Poisoning , Salmonella Infections , Humans , China/epidemiology , Data Collection , Salmonella , Salmonella Food Poisoning/epidemiology , Salmonella Infections/epidemiology , Systematic Reviews as Topic , Meta-Analysis as Topic
2.
PLoS One ; 19(1): e0296935, 2024.
Article in English | MEDLINE | ID: mdl-38261591

ABSTRACT

BACKGROUND: The triglyceride glucose-body mass index (TyG-BMI) has been considered a surrogate marker for assessing insulin resistance. We aimed to correlate the TyG-BMI, triglyceride glucose combined with body mass index, with femoral neck bone mineral density (FN BMD) in non-diabetic elderly men. METHODS: Using data from the National Health and Nutrition Examination Survey (NHANES) database, totally, 1182 eligible men aged ≥ 50 years without diabetes were included in the current study. Smoothed curves were obtained by a two-piecewise linear regression model and the threshold effects were explored by using a smoothing function. RESULTS: TyG-BMI was positive related with and FN BMD with or without adjustment for confounders. However, no typical dose-dependent positive association between TyG-BMI and FN BMD was observed across the TyG-BMI tertiles, indicating a non-linear association. Further analysis by the weighted two-piecewise linear regression model and recursive algorithm suggested that per SD increase in TyG-BMI increased FN BMD by 0.266 gm/cm2 when TyG-BMI lower than 168.20. However, when TyG-BMI is higher than 168.20, FN BMD only increased 0.046 gm/cm2 for per SD increase of TyG-BMI after fully adjustment (OR = 11.258, 95%CI: 6.034, 16.481). Moreover, subgroup analyses showed that higher TyG-BMI levels were related to elevated FN BMD in all groups, suggesting the consistency of the positive association within these stratas. CONCLUSIONS: This study demonstrated that TyG-BMI is positively associated with FN BMD in a nonlinear fashion among elderly men without diabetes, which may be a reliable marker for the early identification of individuals with lower FN BMD.


Subject(s)
Diabetes Mellitus , Femur Neck , Aged , Male , Humans , Body Mass Index , Nutrition Surveys , Glucose , Triglycerides
3.
Int J Med Sci ; 20(11): 1417-1424, 2023.
Article in English | MEDLINE | ID: mdl-37790852

ABSTRACT

Background: Serum triglyceride (TG) was an important biomarker for nonalcoholic fatty liver disease (NAFLD), and the association between TG and incident type 2 diabetes mellitus is still under debate with some studies suggesting that elevated TG increase the risk of incident T2DM while others indicative of a negative relationship. These controversial findings may be partially due to the inclusion of the participants with NAFLD. The association between TG and incident type 2 diabetes mellitus in people with NAFLD remained unclear. Therefore, this study aimed to characterize the relationship between the baseline TG levels and incident type 2 diabetes mellitus in a male Japanese cohort with NAFLD. Methods: A total of 1221 males with NAFLD were enrolled from the Nagala (NAFLD in the Gifu Area Longitudinal analysis) study conducted from 2004 to 2015. Cox proportional hazards models were performed to examine the relationship between baseline TG concentration and incident type 2 diabetes mellitus. A two-piecewise linear regression model was explored to evaluate the threshold effect of the baseline TG levels on type 2 diabetes mellitus incidence by using a smoothing function. Results: During a median follow-up of 6.05 years, 39 males with NAFLD at baseline developed type 2 diabetes mellitus. The risk of incident type 2 diabetes mellitus was significantly associated with baseline TG concentration in males with NAFLD after fully adjustment for confounders, with per 10 mg/dl elevation in TG levels increasing the risk of incident diabetes by 8.5% (HR=1.085, CI=1.039-1.132; P<0.001). However, no typical dose-dependent positive association between type 2 diabetes mellitus incidence and the TG levels was observed across the TG tertiles. Interestingly, a U-shaped association between TG concentration and risk of incident type 2 diabetes mellitus was revealed by the two-piecewise linear regression analysis. Baseline TG concentration lower than the threshold values (TG <53mg/dl) were negatively associated with risk of incident type 2 diabetes mellitus. With each 10mg/dl increase in baseline TG levels, the risk of incident type 2 diabetes mellitus decreased by nearly 59% (HR=0.413, 95% CI=0.220-0.778). In contrast, when TG levels were higher than the threshold values (TG>53mg/dl), the risk of incident diabetes increased 9.1% with every 10mg TG elevation (HR=1.091, 95% CI=1.046-1.137). Conclusions: A U-shaped relationship was observed between baseline TG levels and incident type 2 diabetes mellitus in a male normoglycemic Japanese population with NAFLD, although extrapolation of the finding to other populations should be made with caution.


Subject(s)
Diabetes Mellitus, Type 2 , Non-alcoholic Fatty Liver Disease , Humans , Male , Diabetes Mellitus, Type 2/complications , Triglycerides , Cohort Studies , Incidence , Risk Factors
4.
mSystems ; 8(6): e0088323, 2023 Dec 21.
Article in English | MEDLINE | ID: mdl-37855620

ABSTRACT

IMPORTANCE: Antimicrobial resistance (AMR) has become a significant global challenge, with an estimated 10 million deaths annually by 2050. The emergence of AMR is mainly attributed to mobile genetic elements (MGEs or mobilomes), which accelerate wide dissemination among pathogens. The interaction between mobilomes and AMR genes (or resistomes) in Salmonella, a primary cause of diarrheal diseases that results in over 90 million cases annually, remains poorly understood. The available fragmented or incomplete genomes remain a significant limitation in investigating the relationship between AMR and MGEs. Here, we collected the most extensive closed Salmonella genomes (n = 1,817) from various sources across 58 countries. Notably, our results demonstrate that resistome transmission between Salmonella lineages follows a specific pattern of MGEs and is influenced by external drivers, including certain socioeconomic factors. Therefore, targeted interventions are urgently needed to mitigate the catastrophic consequences of Salmonella AMR.


Subject(s)
Drug Resistance, Bacterial , Salmonella , Salmonella/drug effects , Salmonella/genetics
5.
BMC Med ; 21(1): 388, 2023 10 09.
Article in English | MEDLINE | ID: mdl-37814306

ABSTRACT

BACKGROUND: Dipeptidyl peptidase-4 inhibitors (DPP-4i) have become firmly established in treatment algorithms and national guidelines for improving glycemic control in type 2 diabetes mellitus (T2DM).To report the findings from a multicenter, randomized, double-blind, placebo-controlled phase 3 clinical trial, which was designed to assess the efficacy and safety of a novel DPP-4 inhibitor fotagliptin in treatment-naive patients with T2DM. METHODS: Patients with T2DM were randomized to receive fotagliptin (n = 230), alogliptin (n = 113) or placebo (n = 115) at a 2:1:1 ratio for 24 weeks of double-blind treatment period, followed by an open-label treatment period, making up a total of 52 weeks. The primary efficacy endpoint was to determine the superiority of fotagliptin over placebo in the change of HbA1c from baseline to Week 24. All serious or significant adverse events were recorded. RESULTS: After 24 weeks, mean decreases in HbA1c from baseline were -0.70% for fotagliptin, -0.72% for alogliptin and -0.26% for placebo. Estimated mean treatment differences in HbA1c were -0.44% (95% confidence interval [CI]: -0.62% to -0.27%) for fotagliptin versus placebo, and -0.46% (95% CI: -0.67% to -0.26%) for alogliptin versus placebo, and 0.02% (95%CI: -0.16% to 0.19%; upper limit of 95%CI < margin of 0.4%) for fotagliptin versus alogliptin. So fotagliptin was non-inferior to alogliptin. Compared with subjects with placebo (15.5%), significantly more patients with fotagliptin (37.0%) and alogliptin (35.5%) achieved HbA1c < 7.0% after 24 weeks of treatment. During the whole 52 weeks of treatment, the overall incidence of hypoglycemia was low for both of the fotagliptin and alogliptin groups (1.0% each). No drug-related serious adverse events were observed in any treatment group. CONCLUSIONS: In summary, the study demonstrated improvement in glycemic control and a favorable safety profile for fotagliptin in treatment-naive patients with T2DM. TRIAL REGISTRATION: ClinicalTrail.gov NCT05782192.


Subject(s)
Diabetes Mellitus, Type 2 , Dipeptidyl-Peptidase IV Inhibitors , Humans , Diabetes Mellitus, Type 2/drug therapy , Glycated Hemoglobin , Blood Glucose , Hypoglycemic Agents/adverse effects , Dipeptidyl-Peptidase IV Inhibitors/adverse effects , Double-Blind Method , Treatment Outcome
6.
BMC Endocr Disord ; 22(1): 191, 2022 Jul 27.
Article in English | MEDLINE | ID: mdl-35897092

ABSTRACT

BACKGROUND: Limited data show that changes in fasting plasma glucose (FPG changes) are related to the incidence of type 2 diabetes (T2D). We aimed to correlate FPG changes with incident diabetes and evaluate FPG changes as a marker to screen participants at high risk of T2D in China. METHODS: A total of 116,816 individuals were followed during a median follow-up of 3.10 years by secondary analysis in a nondiabetic Chinese cohort. The turning points were derived from a receiver operating characteristic curve. Hazard ratios (HRs) were evaluated by Cox proportional hazards models. RESULTS: A total of 2669 cases of T2D were identified (788 women and 1881 men). The age-standardized incidence of diabetes was 12.87 per 1000 person-years (women: 11.04; men: 14.69). A nonlinear relationship between FPG changes and incident diabetes is shown by the fitting curves. The curves were categorized into three stages by two turning points (-0.04 and 1.25 mmol/L) and conformed to the hook-like pattern: an initial decrease (stage-1), then a transient sharp elevation (stage-2), followed by a slow increase (stage-3). HRs per SD of FPG changes on incident diabetes varied with stage: stage-1: 0.16 (0.12, 0.23), stage-2: 0.20 (0.15, 0.28) and stage-3: 0.22 (0.16, 0.31). Compared with stage-1, the HR in stage-3 was significantly higher at 28.05 (23.99, 32.79), while the increase in stage-2 was slight at 2.16 (1.79, 2.61), and the HR in stage-3 rose to 30.09 (25.02, 36.19). CONCLUSIONS: FPG changes had a strong correlation with the incidence of T2D and was a steady indicator that was used to distinguish the participants at high risk of diabetes.


Subject(s)
Diabetes Mellitus, Type 2 , Fasting , Blood Glucose , Cohort Studies , Diabetes Mellitus, Type 2/epidemiology , Female , Humans , Incidence , Male , Risk Factors
7.
Article in English | MEDLINE | ID: mdl-34394712

ABSTRACT

RESULTS: Prolonged exposure to palmitate increased the expression of ACE and AngII type 1 receptor (ATR1) and decreased the ACE2 expression, which was partly offset by berberine. In ob/ob mice, berberine increased in tolerance to glucose, improved abnormal ß-cell and α-cell distributions, upregulated ACE2 expression, and decreased autophagosomes and the expression of LC3 and SQSTM1/p62. Autophagosomes and expression of LC3 and SQSTM1/p62 were increased in ACE2KO mice. CONCLUSIONS: We demonstrated that berberine may improve the pancreatic islet function by regulating local RAS-mediated autophagy under metabolic stress.


Subject(s)
Berberine , Islets of Langerhans , Animals , Autophagy , Berberine/metabolism , Berberine/pharmacology , Islets of Langerhans/metabolism , Mice , Mice, Knockout , Peptidyl-Dipeptidase A/metabolism , Renin-Angiotensin System , Stress, Physiological
8.
Acta Diabetol ; 58(7): 869-880, 2021 Jul.
Article in English | MEDLINE | ID: mdl-33651228

ABSTRACT

AIMS: The aim was to systematically review the efficacy and safety of sodium-glucose cotransporter inhibitor (SGLT2i) as an adjunct to insulin at different follow-up durations in randomized, double-blind clinical trials in patients with type 1 diabetes. METHODS: We conducted a search on Medline, Embase, and the Cochrane Library for relevant studies published before May 2020. According to the duration of follow-up, the subgroup analysis included four periods: 1-4, 12-18, 24-26, and 52 weeks. In the five trials included both 24-26 and 52 weeks of follow-up, we compared the efficacy by the placebo-subtracted difference and changes in SGLT2i groups. RESULTS: Fifteen trials including 7109 participants were analyzed. The combination of SGLT2i and insulin improved hemoglobin A1c (HbA1c), fasting plasma glucose (FPG), daily insulin dose, body weight, and blood pressure, which varied greatly by different follow-ups. Compared with %HbA1c at 24-26 weeks, placebo-subtracted differences and changes in the SGLT2i groups slightly increased. SGLT2i plus insulin treatment showed no difference in the occurrence of urinary tract infections (UTIs), hypoglycemia, or severe hypoglycemia but increased the risk of genital tract infections (GTIs) in a duration-dependent manner. SGLT2i treatment was associated with a significantly higher rate of ketone-related SAEs and diabetic ketoacidosis (DKA) at 52 weeks. CONCLUSION: SGLT2i as an add-on therapy to insulin improved glycemic control and body weight and decreased the required dose of insulin without increasing the risk of hypoglycemia. However, after 6 months the benefits of SGLT2is on glycemic control may weaken and the risks of GTIs and DKA increased.


Subject(s)
Diabetes Mellitus, Type 1/drug therapy , Insulin/administration & dosage , Sodium-Glucose Transporter 2 Inhibitors/administration & dosage , Body Weight/drug effects , Diabetes Mellitus, Type 1/blood , Diabetes Mellitus, Type 1/epidemiology , Diabetic Ketoacidosis/blood , Diabetic Ketoacidosis/chemically induced , Diabetic Ketoacidosis/epidemiology , Double-Blind Method , Drug Therapy, Combination/adverse effects , Glycated Hemoglobin/drug effects , Glycated Hemoglobin/metabolism , Humans , Hypoglycemia/chemically induced , Hypoglycemia/epidemiology , Hypoglycemic Agents/administration & dosage , Hypoglycemic Agents/adverse effects , Insulin/adverse effects , Randomized Controlled Trials as Topic/statistics & numerical data , Sodium-Glucose Transporter 2 Inhibitors/adverse effects
9.
Int Heart J ; 62(1): 142-147, 2021 Jan 30.
Article in English | MEDLINE | ID: mdl-33390565

ABSTRACT

The aim of this study was to evaluate the clinical efficacy of N-acetylcysteine (NAC) in the treatment of ST segment elevation myocardial infarction (STEMI).PubMed, EMBASE, Cochrane Library, and Web of Science were searched systematically from the establishment of the database to June 2020. Two researchers independently completed literature screening and data extraction and conducted a meta-analysis.Nine articles including 1419 patients were enrolled. Meta-analysis showed that all-cause mortality [RR = 0.56, 95%CI (0.33, 0.93), P = 0.02], occurrence of major adverse cardiovascular events (MACE) [RR = 0.63, 95%CI (0.47, 0.85), P = 0.002], and myocardial enzyme hs-TnT level [SMD = -0.42, 95%CI (-0.71, -0.13), P = 0.005] were significantly lower in patients with STEMI treated with NAC than those in the control group. There was no significant difference between the NAC group and the control group in new congestive heart failure [RR = 0.94, 95%CI (0.48, 1.82), P = 0.84], ejection fraction [MD = 2.00, 95%CI (-0.59, 4.60), P = 0.13], and CK-MB [SMD = -0.18, 95%CI (-0.47, 0.11), P = 0.23]. There was no significant difference in the occurrence of adverse reactions between the NAC group and the control group [RR = 1.04, 95%CI (0.57-1.89), P = 0.90].NAC can reduce the all-cause mortality and MACE cases of STEMI.


Subject(s)
Acetylcysteine/therapeutic use , Free Radical Scavengers/therapeutic use , Myocardial Infarction/drug therapy , ST Elevation Myocardial Infarction/drug therapy , Acetylcysteine/administration & dosage , Adult , Aged , Aged, 80 and over , Cardiovascular Diseases/epidemiology , Cardiovascular Diseases/mortality , Cardiovascular Diseases/prevention & control , Case-Control Studies , Creatine Kinase, MB Form/metabolism , Female , Free Radical Scavengers/administration & dosage , Heart Failure/mortality , Heart Failure/physiopathology , Heart Failure/prevention & control , Humans , Male , Middle Aged , Myocardial Infarction/metabolism , Myocardial Infarction/mortality , Myocardial Infarction/physiopathology , Percutaneous Coronary Intervention/methods , Randomized Controlled Trials as Topic , ST Elevation Myocardial Infarction/mortality , Stroke Volume , Treatment Outcome , Troponin T/metabolism
10.
Metabolism ; 81: 83-96, 2018 04.
Article in English | MEDLINE | ID: mdl-29225087

ABSTRACT

OBJECTIVE: Angiotensin-converting enzyme 2 (ACE2) has been identified in pancreatic islets and can preserve ß cells. In this study, we aimed to examine the possible role of ACE2 and its end product, angiotensin 1-7 (A1-7), in reducing ß cell dedifferentiation during metabolic stress. METHODS: First, a lineage-tracing experiment was performed to track ß cells in mice fed a high-fat diet (HFD). Second, the ACE2/A1-7 axis was evaluated in the HFD mouse model. Intraperitoneal glucose tolerance tests (IPGTTs) and intraperitoneal insulin tolerance tests (IPITTs) were conducted. Phenotypic changes in ß cells were detected by immunohistochemistry and quantitative real-time PCR. Pancreatic sections were immunostained for vascular endothelial growth factor (VEGF) and inducible nitric oxide synthase (iNOS). Finally, the effects of the ACE2/A1-7 axis were explored in isolated mouse islets exposed to different concentrations of glucose. Glucose-stimulated insulin release and levels of insulin mRNA and OCT4 mRNA were measured. RESULTS: Pancreatic ß cell dedifferentiation occurred both in vitro and in vivo in response to metabolic stress and was accompanied by ACE2 reduction. HFD-induced insulin resistance and glucose intolerance were exacerbated in ACE2-knockout (ACE2KO) mice but were alleviated by exogenous A1-7 in C57BL/6J mice. Approximately 20% of ß cells were dedifferentiated in ACE2KO mice fed a standard rodent chow diet (SD). A higher percentage of dedifferentiated ß cells was detected in ACE2KO mice than in wild-type (WT) mice under HFD conditions. In contrast, the administration of A1-7 alleviated HFD-induced ß cell dedifferentiation in C57BL/6J mice. Moreover, the exogenous injection of A1-7 improved microcirculation in islets and decreased the production of iNOS in islets of C57BL/6J mice fed an HFD. Additionally, ACE2 was found to be mainly expressed in α cells of mice, while Mas, the receptor of A1-7, was distributed in ß cells. CONCLUSIONS: Overall, this study is the first to demonstrate that the ACE2/A1-7/Mas axis may be one of the intra-islet paracrine mechanisms of communication between α and ß cells. Enhancing the ACE2/A1-7 axis exerts a protective effect by ameliorating ß cell dedifferentiation, and this effect might be partially mediated through improvements in islet microcirculation and suppression of islet iNOS.


Subject(s)
Angiotensin I/physiology , Cell Dedifferentiation , Insulin-Secreting Cells/cytology , Peptide Fragments/physiology , Peptidyl-Dipeptidase A/physiology , Angiotensin-Converting Enzyme 2 , Animals , Cell Lineage , Diet, High-Fat , Glucose Intolerance/etiology , Insulin/genetics , Insulin/metabolism , Insulin Resistance , Insulin Secretion , Insulin-Secreting Cells/physiology , Male , Mice , Mice, Inbred C57BL , Weight Gain
11.
Int J Mol Med ; 36(1): 173-85, 2015 Jul.
Article in English | MEDLINE | ID: mdl-25976560

ABSTRACT

The number of pro-α cells is known to increase in response to ß cell injury and these cells then generate glucagon-like peptide-1 (GLP-1), thus attenuating the development of diabetes. The aim of the present study was to further examine the role and the mechanisms responsible for intra-islet GLP-1 production as a self-protective response against lipotoxicity. The levels of the key enzyme, prohormone convertase 1/3 (PC1/3), as well as the synthesis and release of GLP-1 in models of lipotoxicity were measured. Furthermore, islet viability, apoptosis, oxidative stress and inflammation, as well as islet structure were assessed after altering GLP-1 receptor signaling. Both prolonged exposure to palmitate and a high-fat diet facilitated PC1/3 expression, as well as the synthesis and release of GLP-1 induced by ß cell injury and the generation of pro-α cells. Prolonged exposure to palmitate increased reactive oxygen species (ROS) production, and the antioxidant, N-acetylcysteine (NAC), partially prevented the detrimental effects induced by palmitate on ß cells, resulting in decreased GLP-1 levels. Furthermore, the inhibition of GLP-1 receptor (GLP-1R) signaling by treatment with exendin­(9-39) further decreased cell viability, increased cell apoptosis and caused a stronger inhibition of the ß cell-specific transcription factor, pancreatic duodenal homeobox 1 (PDX1). Moreover, treatment with the GLP-1R agonist, liraglutide, normalized islet structure and function, resulting in a decrease in cell death and in the amelioration of ß cell marker expression. Importantly, liraglutide maintained the oxidative balance and decreased inflammatory factor and p65 expression. Overall, our data demonstrate that an increase in the number of pro-α cells and the activation of the intra-islet GLP-1 system comprise a self-defense mechanism for enhancing ß cell survival to combat lipid overload, which is in part mediated by oxidative stress and inflammation.


Subject(s)
Diet, High-Fat , Glucagon-Like Peptide 1/metabolism , Glucagon-Secreting Cells/cytology , Insulin-Secreting Cells/metabolism , Palmitates/pharmacology , Acetylcysteine/pharmacology , Animals , Apoptosis/drug effects , Cell Survival/drug effects , Cells, Cultured , Glucagon-Like Peptide-1 Receptor/agonists , Glucagon-Like Peptide-1 Receptor/antagonists & inhibitors , Homeodomain Proteins/antagonists & inhibitors , Inflammation/pathology , Liraglutide/pharmacology , Male , Mice , Mice, Inbred C57BL , Oxidative Stress/physiology , Peptide Fragments/pharmacology , Proprotein Convertase 1/biosynthesis , Proprotein Convertase 1/metabolism , Reactive Oxygen Species/metabolism , Signal Transduction/physiology , Trans-Activators/antagonists & inhibitors , Transcription Factor RelA/biosynthesis
12.
Cancer Lett ; 283(1): 20-8, 2009 Sep 28.
Article in English | MEDLINE | ID: mdl-19375219

ABSTRACT

Radioresistant cells have been shown to correlate with poor outcome after radiotherapy. Here, we found that human telomerase reverse transcriptase promoter (hTERTp) had lower activity in laryngeal squamous carcinomas cells than in radioresistant variant cells. Combining radiotherapy with plasmid phTERTp-HRP, in which expression of enzyme horseradish peroxidase (HRP) controlled by hTERTp, resulted in increased apoptosis and necrosis of tumor cells after prodrug indole-3-acetic acid (IAA; converted by HRP into a cytotoxin) incubation. Volume and wet weight of xenograft tumor were reduced more in the combination groups. These data suggest that hTERTp has potential use in targeted cancer gene therapy, especially for radioresistant tumors. Combining radiotherapy with hTERTp-HRP/IAA may overcome radioresistance in laryngeal squamous carcinomas cells and amplify the killing effect in targeted cancer cells.


Subject(s)
Carcinoma, Squamous Cell/therapy , Genetic Therapy/methods , Laryngeal Neoplasms/therapy , Radiotherapy/methods , Telomerase/genetics , Animals , Apoptosis/physiology , Apoptosis/radiation effects , Cell Line, Tumor , Combined Modality Therapy , Female , Genes, Transgenic, Suicide/genetics , Humans , In Situ Nick-End Labeling , Mice , Mice, Nude , Promoter Regions, Genetic , Radiation Tolerance , Reverse Transcriptase Polymerase Chain Reaction , Xenograft Model Antitumor Assays
13.
Mol Med Rep ; 2(6): 1017-22, 2009.
Article in English | MEDLINE | ID: mdl-21475937

ABSTRACT

Human telomerase reverse transcriptase (hTERT) promoter has been proposed in cancer-targeted gene therapy. However, this promoter has not been strong enough to achieve therapeutic levels of transgene expression. We favor the hypothesis that telomerase may participate in the process of DNA repair and that the up-regulation of hTERT promoter activity may be a reaction to DNA damage. In previous investigations, we tested an 'indirected-activator' strategy that utilizes radiation to increase the activity of the hTERT promoter. The purpose of the present study was to implement a strategy using cisplatin to enhance hTERT promoter activity. The results indicate that, in human uterine cervical cancer (HeLa) cells exposed to 5 µg/ml cisplatin, the hTERT promoter had 3.1-fold increased activity compared to untreated cells. In addition, the combination of cisplatin and hTERT promoter-mediated horseradish peroxidase/indole-3-acetic acid gene-directed enzyme prodrug therapy induced cell cycle arrest at the S phase and apoptosis leading to a more significant reduction in cell viability. These findings suggest that hTERT promoter-mediated gene therapy is improved when combined with cisplatin.

14.
Zhonghua Zhong Liu Za Zhi ; 30(10): 733-6, 2008 Oct.
Article in Chinese | MEDLINE | ID: mdl-19173799

ABSTRACT

OBJECTIVE: To explore the therapeutic efficiency of human telomerase reverse transcriptase promoter (hTERTp) mediated horseradish peroxidase (HRP) catalyzed effects of indole-3-acetic (IAA) on laryngeal squamous cell carcinoma with different radiosensitivity in vivo. METHODS: Human laryngeal squamous cell carcinoma Hep-2 and Hep-2R cells were transplanted into nude mice. After growing to about 30 approximately 50 mm3, the tumor-bearing mice were randomly divided into eight groups: Hep-2 line: combined group (A), gene group (B), radiation group (C) and blank group (D); Hep-2R line: combined group (AR), gene group (BR), radiation group (CR) and blank group (DR). The phTERTp-HRP was delivered by intratumoral injection and the IAA by intraperitoneal injection, combined with 2 Gy daily radiation to a total dose of 30 Gy. The tumor volume was recorded. The cell apoptosis was detected by terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling (TUNEL) assay. The expression of HRP protein was detected by AP immunohistochemisty. RESULTS: The tumor growth of combined groups was attenuated significantly and the tumor volume of Hep-2R blank group was the largest. The inhibition rate of each group was: A: 54.8%, B: 10.0%, C: 31.9%; AR: 52.7%, BR: 24.8%, CR: 17.0%. In the combined groups, necrosis and apoptosis of tumor cells were observed under the light microscope and the apoptotic index [A (16.6 +/- 1.3)% vs. AR (17.6 +/- 1.3)%] of tumor cells was highest (P < 0.05). The HRP protein expression of BR (33.3 +/- 8.9)% was higher than that of B (21.9 +/- 5.7)%, which was directly up-regulated in the tumors (45.0% vs. 54.8%, P < 0.05) after radiation. CONCLUSION: In the Hep-2- and Hep-2R-transplantation tumors in nude mice, hTERTp can be induced by radiation and enhance the expression of horseradish peroxidase (HRP) gene according to telomerase activity. hTERTp-HRP/IAA system, which has synergistic effects with radiation and inhibits the tumor growth by induction of apoptosis and necrosis, may be a new gene-radiation strategy for the treatment of laryngeal carcinoma.


Subject(s)
Genetic Therapy/methods , Horseradish Peroxidase/genetics , Laryngeal Neoplasms/therapy , Radiotherapy/methods , Telomerase/genetics , Animals , Apoptosis , Cell Line, Tumor , Combined Modality Therapy , Female , Horseradish Peroxidase/metabolism , Humans , Indoleacetic Acids/metabolism , Indoleacetic Acids/pharmacology , Laryngeal Neoplasms/metabolism , Laryngeal Neoplasms/pathology , Mice , Mice, Inbred BALB C , Mice, Nude , Neoplasm Transplantation , Promoter Regions, Genetic , Radiation Tolerance , Random Allocation , Tumor Burden
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