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1.
Mol Ther Oncolytics ; 27: 89-99, 2022 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-36321136

RESUMO

Genetic modification of coxsackievirus B3 (CVB3) by inserting target sequences (TS) of tumor-suppressive and/or organ-selective microRNAs (miRs) into viral genome can efficiently eliminate viral pathogenesis without significant impacts on its oncolytic activity. Nonetheless, reversion mutants (loss of miR-TS inserts) were identified as early as day 35 post-injection in ∼40% immunodeficient mice. To improve the stability, here we re-engineered CVB3 by (1) replacing the same length of viral genome at the non-coding region with TS of cardiac-selective miR-1/miR-133 and pancreas-enriched miR-216/miR-375 or (2) inserting the above miR-TS into the coding region (i.e., P1 region) of viral genome. Serial passaging of these newly established miR-CVB3s in cultured cells for 20 rounds demonstrated significantly improved stability compared with the first-generation miR-CVB3 with 5'UTR insertion of miR-TS. The safety and stability of these new miR-CVB3s was verified in immunocompetent mice. Moreover, we showed that these new viruses retained the ability to suppress lung tumor growth in a xenograft mouse model. Finally, we observed that miR-CVB3 with insertion in P1 region was more stable than miR-CVB3 with preserved length of the 5'UTR, whereas the latter displayed significantly higher oncolytic activity. Overall, we presented here valid strategies to enhance the genomic stability of miR-CVB3 for virotherapy.

2.
PLoS One ; 16(8): e0254620, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34351931

RESUMO

Estimating parameters accurately in groundwater models for aquifers is challenging because the models are non-explicit solutions of complex partial differential equations. Modern research methods, such as Monte Carlo methods and metaheuristic algorithms, for searching an efficient design to estimate model parameters require hundreds, if not thousands of model calls, making the computational cost prohibitive. One method to circumvent the problem and gain valuable insight on the behavior of groundwater is to first apply a Galerkin method and convert the system of partial differential equations governing the flow to a discrete problem and then use a Proper Orthogonal Decomposition to project the high-dimensional model space of the original groundwater model to create a reduced groundwater model with much lower dimensions. The reduced model can be solved several orders of magnitude faster than the full model and able to provide an accurate estimate of the full model. The task is still challenging because the optimization problem is non-convex, non-differentiable and there are continuous variables and integer-valued variables to optimize. Following convention, heuristic algorithms and a combination is used search to find efficient designs for the reduced groundwater model using various optimality criteria. The main goals are to introduce new design criteria and the concept of design efficiency for experimental design research in hydrology. The two criteria have good utility but interestingly, do not seem to have been implemented in hydrology. In addition, design efficiency is introduced. Design efficiency is a method to assess how robust a design is under a change of criteria. The latter is an important issue because the design criterion may be subjectively selected and it is well known that an optimal design can perform poorly under another criterion. It is thus desirable that the implemented design has relatively high efficiencies under a few criteria. As applications, two heuristic algorithms are used to find optimal designs for a small synthetic aquifer design problem and a design problem for a large-scale groundwater model and assess their robustness properties to other optimality criteria. The results show the proof of concept is workable for finding a more informed and efficient model-based design for a water resource study.


Assuntos
Água Subterrânea/normas , Hidrologia/estatística & dados numéricos , Modelos Teóricos , Recursos Hídricos , Algoritmos , Simulação por Computador/estatística & dados numéricos , Governo , Heurística , Humanos , Método de Monte Carlo
4.
Mol Ther Oncolytics ; 16: 207-218, 2020 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-32123721

RESUMO

We recently discovered that coxsackievirus B3 (CVB3) is a potent oncolytic virus against KRAS mutant lung adenocarcinoma. Nevertheless, the evident toxicity restricts the use of wild-type (WT)-CVB3 for cancer therapy. The current study aims to engineer the CVB3 to decrease its toxicity and to extend our previous research to determine its safety and efficacy in treating TP53/RB1 mutant small-cell lung cancer (SCLC). A microRNA-modified CVB3 (miR-CVB3) was generated via inserting multiple copies of tumor-suppressive miR-145/miR-143 target sequences into the viral genome. In vitro experiments revealed that miR-CVB3 retained the ability to infect and lyse KRAS mutant lung adenocarcinoma and TP53/RB1-mutant SCLC cells, but with a markedly reduced cytotoxicity toward cardiomyocytes. In vivo study using a TP53/RB1-mutant SCLC xenograft model demonstrated that a single dose of miR-CVB3 via systemic administration resulted in a significant tumor regression. Most strikingly, mice treated with miR-CVB3 exhibited greatly attenuated cardiotoxicities and decreased viral titers compared to WT-CVB3-treated mice. Collectively, we generated a recombinant CVB3 that is powerful in destroying both KRAS mutant lung adenocarcinoma and TP53/RB1-mutant SCLC, with a negligible toxicity toward normal tissues. Future investigation is needed to address the issue of genome instability of miR-CVB3, which was observed in ~40% of mice after a prolonged treatment.

5.
Mol Ther Oncolytics ; 14: 266-278, 2019 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-31463367

RESUMO

KRAS mutant (KRAS mut ) lung adenocarcinoma is a refractory cancer without available targeted therapy. The current study explored the possibility to develop coxsackievirus type B3 (CVB3) as an oncolytic agent for the treatment of KRAS mut lung adenocarcinoma. In cultured cells, we discovered that CVB3 selectively infects and lyses KRAS mut lung adenocarcinoma cells (A549, H2030, and H23), while sparing normal lung epithelial cells (primary, BEAS2B, HPL1D, and 1HAEo) and EGFR mut lung adenocarcinoma cells (HCC4006, PC9, H3255, and H1975). Using stable cells expressing a single driver mutation of either KRAS G12V or EGFR L858R in normal lung epithelial cells (HPL1D), we further showed that CVB3 specifically kills HPL1D-KRAS G12V cells with minimal harm to HPL1D-EGFR L858R and control cells. Mechanistically, we demonstrated that aberrant activation of extracellular signal-regulated kinase 1/2 (ERK1/2) and compromised type I interferon immune response in KRAS mut lung adenocarcinoma cells serve as key factors contributing to the sensitivity to CVB3-induced cytotoxicity. Lastly, we conducted in vivo xenograft studies using two immunocompromised mouse models. Our results revealed that intratumoral injection of CVB3 results in a marked tumor regression of KRAS mut lung adenocarcinoma in both non-obese diabetic (NOD) severe combined immunodeficiency (SCID) gamma (NSG) and NOD-SCID xenograft models. Together, our findings suggest that CVB3 is an excellent candidate to be further developed as a targeted therapy for KRAS mut lung adenocarcinoma.

6.
Virol J ; 10: 241, 2013 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-23876001

RESUMO

BACKGROUND: Non-small cell lung cancer (NSCLC) is the leading cause of cancer-related mortality worldwide, and novel treatment modalities to improve the prognosis of patients with advanced disease are highly desirable. Oncolytic virotherapy is a promising approach for the treatment of advanced NSCLC. MicroRNAs (miRNAs) may be a factor in the regulation of tumor-specific viral replication. The purpose of this study was to investigate whether miRNA-145 regulated oncolytic herpes simplex virus-1 (HSV-1) can selectively kill NSCLC cells with reduced collateral damage to normal cells. METHODS: We incorporated 4 copies of miRNA-145 target sequences into the 3'-untranslated region of an HSV-1 essential viral gene, ICP27, to create AP27i145 amplicon viruses and tested their target specificity and toxicity on normal cells and lung cancer cells in vitro. RESULTS: miRNA-145 expression in normal cells was higher than that in NSCLC cells. AP27i145 replication was inversely correlated with the expression of miRNA-145 in infected cells. This oncolytic HSV-1 selectively reduced cell proliferation and prevented the colony formation of NSCLC cells. The combination of radiotherapy and AP27i145 infection was significantly more potent in killing cancer cells than each therapy alone. CONCLUSIONS: miRNA-145-regulated oncolytic HSV-1 is a promising agent for the treatment of NSCLC.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/virologia , Regulação Viral da Expressão Gênica , Herpesvirus Humano 1/fisiologia , Interações Hospedeiro-Patógeno , MicroRNAs/metabolismo , Vírus Oncolíticos/fisiologia , Regiões 3' não Traduzidas , Sítios de Ligação , Proliferação de Células , Sobrevivência Celular , DNA Viral/genética , Herpesvirus Humano 1/genética , Herpesvirus Humano 1/crescimento & desenvolvimento , Humanos , Vírus Oncolíticos/genética , Vírus Oncolíticos/crescimento & desenvolvimento
7.
Mol Ther ; 18(5): 929-35, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20179676

RESUMO

The aim of this project was to demonstrate that an oncolytic herpes simplex virus type 1 (HSV-1) can replicate in a tissue- and tumor-specific fashion through both transcriptional (prostate-specific promoter, ARR(2)PB) and translational (5'-untranslated regions (5'UTRs) of rFGF-2) regulation of an essential viral gene, ICP27. We generated two recombinant viruses, ARR(2)PB-ICP27 (A27) and ARR(2)PB-5'UTR-ICP27 (AU27) and tested their efficacy and toxicity both in vitro and in vivo. The ARR(2)PB promoter caused overexpression of ICP27 gene in the presence of activated androgen receptors (ARs) and increased viral replication in prostate cells. However, this transcriptional upregulation was effectively constrained by the 5'UTR-mediated translational regulation. Mice bearing human prostate LNCaP tumors, treated with a single intravenous injection of 5 x 10(7) plaque-forming units (pfu) of AU27 virus exhibited a >85% reduction in tumor size at day 28 after viral injection. Although active viral replication was readily evident in the tumors, no viral DNA was detectable in normal organs as measured by real-time PCR analyses. In conclusion, a transcriptional and translational dual-regulated (TTDR) viral essential gene expression can increase both viral lytic activity and tumor specificity, and this provides a basis for the development of a novel tumor-specific oncolytic virus for systemic treatment of locally advanced and metastatic prostate cancers.


Assuntos
Herpesvirus Humano 1/fisiologia , Terapia Viral Oncolítica/métodos , Neoplasias da Próstata/terapia , Animais , Western Blotting , Linhagem Celular Tumoral , Herpesvirus Humano 1/genética , Humanos , Masculino , Camundongos , Camundongos Nus , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Ensaios Antitumorais Modelo de Xenoenxerto
8.
Clin Cancer Res ; 15(16): 5126-35, 2009 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-19671871

RESUMO

PURPOSE: Advanced castration-resistant prostate cancer, for which there are few treatment options, remains one of the leading causes of cancer death. MicroRNAs (miRNA) have provided a new opportunity for more stringent regulation of tumor-specific viral replication. The purpose of this study was to provide a proof-of-principle that miRNA-regulated oncolytic herpes simplex virus-1 (HSV-1) virus can selectively target cancer cells with reduced toxicity to normal tissues. EXPERIMENTAL DESIGN: We incorporated multiple copies of miRNA complementary target sequences (for miR-143 or miR-145) into the 3'-untranslated region (3'-UTR) of an HSV-1 essential viral gene, ICP4, to create CMV-ICP4-143T and CMV-ICP4-145T amplicon viruses and tested their targeting specificity and efficacy both in vitro and in vivo. RESULTS: Although miR-143 and miR-145 are highly expressed in normal tissues, they are significantly down-regulated in prostate cancer cells. We further showed that miR-143 and miR-145 inhibited the expression of the ICP4 gene at the translational level by targeting the corresponding 3'-UTR in a dose-dependent manner. This enabled selective viral replication in prostate cancer cells. When mice bearing LNCaP human prostate tumors were treated with these miRNA-regulated oncolytic viruses, a >80% reduction in tumor volume was observed, with significantly attenuated virulence to normal tissues in comparison with control amplicon viruses not carrying these 3'-UTR sequences. CONCLUSION: Our study is the first to show that inclusion of specific miRNA target sequences into the 3'-UTR of an essential HSV-1 gene is a viable strategy for restricting viral replication and oncolysis to cancer cells while sparing normal tissues.


Assuntos
Herpesvirus Humano 1/fisiologia , MicroRNAs/fisiologia , Terapia Viral Oncolítica/métodos , Vírus Oncolíticos/fisiologia , Neoplasias da Próstata/terapia , Replicação Viral/genética , Animais , Morte Celular/genética , Células Cultivadas , Chlorocebus aethiops , Marcação de Genes/métodos , Herpesvirus Humano 1/genética , Humanos , Masculino , Camundongos , Camundongos Nus , Vírus Oncolíticos/genética , Especificidade de Órgãos/genética , Neoplasias da Próstata/patologia , Resultado do Tratamento , Células Vero , Ensaios Antitumorais Modelo de Xenoenxerto
9.
J Nat Prod ; 70(2): 259-64, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17261067

RESUMO

20S-Protopanaxadiol (1) is an aglycon metabolic derivative of the protopanaxadiol-type ginseng saponins. In the present study, 1 was used to induce cytotoxicity for two human glioma cell lines, SF188 and U87MG. For the SF188 cells, 1 activated caspases-3, -8, -7, and -9 within 3 h and induced rapid apoptosis, which could be partially inhibited by a general caspase blocker and completely abolished when the caspase blocker was used in combination with an antioxidant. Compound 1 also induced cell death in U87MG cells but did not activate any caspases in these cells. Monodansylcadaverine staining showed that 1 induced dramatic autophagy in both cell lines. Elevated levels of superoxide anion in both cells and reduced levels of phosphorylated Akt in U87MG cells were also demonstrated. These results showed that 20S-protopanaxadiol (1) induces different forms of programmed cell death, including both typical apoptosis and autophagy through both caspase-dependent and -independent mechanisms.


Assuntos
Caspases/metabolismo , Morte Celular/efeitos dos fármacos , Sapogeninas/farmacologia , Triterpenos/farmacologia , Glioma/metabolismo , Humanos , Estrutura Molecular
10.
Anticancer Res ; 25(3B): 2049-54, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16158944

RESUMO

BACKGROUND: The wild-type herpes simplex virus type 1 (HSV-1) has strong infectivity and cytolytic effect on almost all types of mammalian cells. Genetic engineering can now restrict this cytolysis to only malignant cells. G207 is an oncolytic HSV-1 vector developed based on this strategy. MATERIALS AND METHODS: We used G207 as the backbone and integrated the exogenous endostatin-angiostatin fusion protein gene to generate a new vector, AE618. RESULTS: Marked expressions of fusion protein in A549 and H460 lung cancer cells and culture medium were found 24 hours after treatment with AE618. In comparison with the G207 treatment group, the secreted protein from H460 cells treated with AE618 significantly inhibited the growth of human umbilical vein endothelial cells (HUVEC). AE618 also significantly inhibited the growth of xenografted tumors in vivo. CONCLUSION: We propose that AE618 has the potential to be a novel anticancer agent with both oncolytic and anti-angiogenesis effects.


Assuntos
Angiostatinas/genética , Carcinoma Pulmonar de Células não Pequenas/terapia , Endostatinas/genética , Terapia Genética/métodos , Neoplasias Pulmonares/terapia , Proteínas Recombinantes de Fusão/genética , Angiostatinas/biossíntese , Animais , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Carcinoma Pulmonar de Células não Pequenas/virologia , Linhagem Celular Tumoral , Endostatinas/biossíntese , Células Endoteliais/virologia , Vetores Genéticos/genética , Herpesvirus Humano 1/genética , Humanos , Interleucina-12/genética , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/virologia , Camundongos , Camundongos SCID , Sinais Direcionadores de Proteínas/genética , Proteínas Recombinantes de Fusão/biossíntese , Ensaios Antitumorais Modelo de Xenoenxerto
11.
Can J Physiol Pharmacol ; 82(7): 431-7, 2004 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15389289

RESUMO

Rh2 is a ginsenoside extracted from ginseng that has drawn attention in a few laboratories in Asian countries because of its potential tumor-inhibitory effect. In the present study, we tested Rh2 on many tumor-cell lines for its effects on cell proliferation, induction of apoptosis, and potential interaction with conventional chemotherapy agents. Our results showed that Rh2 inhibited cell growth by G1 arrest at low concentrations and induced apoptosis at high concentrations in a variety of tumor-cell lines, possibly through activation of caspases. The growth arrest and apoptosis may be mediated by 2 separate mechanisms. Apoptosis is not dependent on expression of the wild-type p53 nor the caspase 3. In addition, the apoptosis induced by Rh2 was mediated through glucocorticoid receptors. Most interestingly, Rh2 can act either additively or synergistically with chemotherapy drugs on cancer cells. Particularly, it hypersensitized multidrug-resistant breast cancer cells to paclitaxel. These results suggest that Rh2 possesses strong tumor-inhibiting properties, and potentially can be used in treatments for multidrug-resistant cancers, especially when it is used in combination with conventional chemotherapy agents.


Assuntos
Antineoplásicos/farmacologia , Ginsenosídeos/farmacologia , Panax/química , Animais , Apoptose , Caspase 3 , Caspases/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Interações Medicamentosas , Resistência a Múltiplos Medicamentos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Mitoxantrona/farmacologia , Transplante de Neoplasias , Neoplasias Experimentais/tratamento farmacológico , Paclitaxel/farmacologia , Extratos Vegetais/farmacologia , Receptores de Glucocorticoides/metabolismo , Proteína Supressora de Tumor p53/metabolismo
12.
Ground Water ; 41(2): 156-69, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12656282

RESUMO

This research develops a methodology for parameter structure identification in ground water modeling. For a given set of observations, parameter structure identification seeks to identify the parameter dimension, its corresponding parameter pattern and values. Voronoi tessellation is used to parameterize the unknown distributed parameter into a number of zones. Accordingly, the parameter structure identification problem is equivalent to finding the number and locations as well as the values of the basis points associated with the Voronoi tessellation. A genetic algorithm (GA) is allied with a grid search method and a quasi-Newton algorithm to solve the inverse problem. GA is first used to search for the near-optimal parameter pattern and values. Next, a grid search method and a quasi-Newton algorithm iteratively improve the GA's estimates. Sensitivities of state variables to parameters are calculated by the sensitivity-equation method. MODFLOW and MT3DMS are employed to solve the coupled flow and transport model as well as the derived sensitivity equations. The optimal parameter dimension is determined using criteria based on parameter uncertainty and parameter structure discrimination. Numerical experiments are conducted to demonstrate the proposed methodology, in which the true transmissivity field is characterized by either a continuous distribution or a distribution that can be characterized by zones. We conclude that the optimized transmissivity zones capture the trend and distribution of the true transmissivity field.


Assuntos
Modelos Teóricos , Movimentos da Água , Abastecimento de Água , Algoritmos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Solo
13.
Can J Cardiol ; 17(4): 467-70, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11329547

RESUMO

Pulmonary artery catheter (PAC) is a commonly used monitor in cardiac surgery. Pulmonary valve injury from the balloon of the pulmonary artery catheter is exceedingly rare; its description by transesophageal echocardiography is nonexistent in the literature. A patient is reported who developed a flail anterior pulmonary leaflet several days after successful myectomy for hypertrophic cardiomyopathy. The temporal sequence of PAC use and four transesophageal echocardiography studies over 13 days, with the first three showing normal pulmonary valves, suggested pulmonary valve trauma, most likely from a Swan-Ganz catheter, as the etiology. Partial damage to the pulmonary valve from the original surgery may have predisposed the patient to further damage when the PAC was reintroduced in the intensive care unit.


Assuntos
Cardiomiopatia Hipertrófica/terapia , Cateterismo de Swan-Ganz/efeitos adversos , Insuficiência da Valva Pulmonar/complicações , Valva Pulmonar/lesões , Ecocardiografia Transesofagiana , Humanos , Masculino , Pessoa de Meia-Idade , Valva Pulmonar/diagnóstico por imagem
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