Controversies in targeted therapy of adult T cell leukemia/lymphoma: ON target or OFF target effects?

PubMed

Nasr, Rihab; El Hajj, Hiba; Kfoury, Youmna; de Thé, Hugues; Hermine, Olivier; Bazarbachi, Ali

2011-06-01

Adult T cell leukemia/lymphoma (ATL) represents an ideal model for targeted therapy because of intrinsic chemo-resistance of ATL cells and the presence of two well identified targets: the HTLV-I retrovirus and the viral oncoprotein Tax. The combination of zidovudine (AZT) and interferon-alpha (IFN) has a dramatic impact on survival of ATL patients. Although the mechanism of action remains unclear, arguments in favor or against a direct antiviral effect will be discussed. Yet, most patients relapse and alternative therapies are mandatory. IFN and arsenic trioxide induce Tax proteolysis, synergize to induce apoptosis in ATL cells and cure Tax-driven ATL in mice through specific targeting of leukemia initiating cell activity. These results provide a biological basis for the clinical success of arsenic/IFN/AZT therapy in ATL patients and suggest that both extinction of viral replication (AZT) and Tax degradation (arsenic/IFN) are needed to cure ATL.

Antiviral Therapy in Steroid-refractory Ulcerative Colitis with Cytomegalovirus: Systematic Review and Meta-analysis.

PubMed

Shukla, Tushar; Singh, Siddharth; Loftus, Edward V; Bruining, David H; McCurdy, Jeffrey D

2015-11-01

The role of antiviral therapy in patients with ulcerative colitis (UC) with cytomegalovirus (CMV) remains unclear. We therefore performed a systematic review and meta-analysis to assess the association between antiviral therapy and the risk of colectomy. Multiple electronic databases were searched systematically through July 2014 for studies reporting the risk of colectomy in patients with UC with CMV stratified by treatment with antiviral agents. Colectomy rates were assessed for the overall cohort and stratified by corticosteroid (CS) refractoriness. We estimated summary odds ratios and 95% confidence intervals, using random-effects model, and used Grading of Recommendations Assessment, Development, and Evaluation criteria to appraise the quality of evidence. Fifteen observational studies (333 patients with UC with CMV, 43.2% treated with antiviral agents) were identified, of which 8 stratified patients according to CS-refractory disease (55.4% treated with antiviral agents). Antiviral therapy resulted in a significantly lower risk of colectomy in patients with CS-refractory disease (odds ratio, 0.20; 95% confidence interval, 0.08-0.49; I = 0%) but not in the overall population of patients with UC (odds ratio, 0.92; 95% confidence interval, 0.31-2.76; I = 65). The quality evidence was low. The results were stable when restricting the analysis to patients with a tissue diagnosis of CMV and studies that defined CS-refractory disease as a failure to respond to intravenous CS. Antiviral therapy may benefit a subgroup of patients with UC who are refractory to CS. Further prospective trials are required to confirm these findings.

Drug-induced Sweet's syndrome secondary to hepatitis C antiviral therapy.

PubMed

Gheorghe, Liana; Cotruta, Bogdan; Trifu, Viorel; Cotruta, Cristina; Becheanu, Gabriel; Gheorghe, Cristian

2008-09-01

Pegylated interferon-alpha in combination with ribavirin currently represents the therapeutic standard for the hepatitis C virus infection. Interferon based therapy may be responsible for many cutaneous side effects. We report a case of drug-induced Sweet's syndrome secondary to hepatitis C antiviral therapy. To our knowledge, this is the first reported case of Sweet's syndrome in association with pegylated interferon-alpha therapy.

Controversies in Targeted Therapy of Adult T Cell Leukemia/Lymphoma: ON Target or OFF Target Effects?

PubMed Central

Nasr, Rihab; Hajj, Hiba El; Kfoury, Youmna; de Thé, Hugues; Hermine, Olivier; Bazarbachi, Ali

2011-01-01

Adult T cell leukemia/lymphoma (ATL) represents an ideal model for targeted therapy because of intrinsic chemo-resistance of ATL cells and the presence of two well identified targets: the HTLV-I retrovirus and the viral oncoprotein Tax. The combination of zidovudine (AZT) and interferon-alpha (IFN) has a dramatic impact on survival of ATL patients. Although the mechanism of action remains unclear, arguments in favor or against a direct antiviral effect will be discussed. Yet, most patients relapse and alternative therapies are mandatory. IFN and arsenic trioxide induce Tax proteolysis, synergize to induce apoptosis in ATL cells and cure Tax-driven ATL in mice through specific targeting of leukemia initiating cell activity. These results provide a biological basis for the clinical success of arsenic/IFN/AZT therapy in ATL patients and suggest that both extinction of viral replication (AZT) and Tax degradation (arsenic/IFN) are needed to cure ATL. PMID:21994752

Options for the management of antiviral resistance during hepatitis B therapy: reflections on battles over a decade

PubMed Central

2013-01-01

Although much advancement has been achieved in the treatment of chronic hepatitis B, antiviral resistance is still a challenging issue. Previous generation antiviral agents have already developed resistance in a number of patients, and it is still being used especially in resource limited countries. Once antiviral resistance occurs, it predisposes to subsequent resistance, resulting in multidrug resistance. Therefore, prevention of initial antiviral resistance is the most important strategy, and appropriate choice and modification of therapy would be the cornerstone in avoiding treatment failures. Until now, management of antiviral resistance has been evolving from sequential therapy to combination therapy. In the era of tenofovir, the paradigm shifts again, and we have to decide when to switch and when to combine on the basis of newly emerging clinical data. We expect future eradication of chronic hepatitis B virus infection by proper prevention and optimal management of antiviral resistance. PMID:24133659

HIV-1 Gag as an Antiviral Target: Development of Assembly and Maturation Inhibitors.

PubMed

Spearman, Paul

2016-01-01

HIV-1 Gag is the master orchestrator of particle assembly. The central role of Gag at multiple stages of the HIV lifecycle has led to efforts to develop drugs that directly target Gag and prevent the formation and release of infectious particles. Until recently, however, only the catalytic site protease inhibitors have been available to inhibit late stages of HIV replication. This review summarizes the current state of development of antivirals that target Gag or disrupt late events in the retrovirus lifecycle such as maturation of the viral capsid. Maturation inhibitors represent an exciting new series of antiviral compounds, including those that specifically target CA-SP1 cleavage and the allosteric integrase inhibitors that inhibit maturation by a completely different mechanism. Numerous small molecules and peptides targeting CA have been studied in attempts to disrupt steps in assembly. Efforts to target CA have recently gained considerable momentum from the development of small molecules that bind CA and alter capsid stability at the post-entry stage of the lifecycle. Efforts to develop antivirals that inhibit incorporation of genomic RNA or to inhibit late budding events remain in preliminary stages of development. Overall, the development of novel antivirals targeting Gag and the late stages in HIV replication appears much closer to success than ever, with the new maturation inhibitors leading the way.

Effects of Complementary Combination Therapy of Korean Red Ginseng and Antiviral Agents in Chronic Hepatitis B.

PubMed

Choi, Seung-Hwa; Yang, Keum-Jin; Lee, Dong-Soo

2016-12-01

Chronic hepatitis B management is commonly targeted at reducing viral replication. However, the currently available antiviral therapies are associated with some problems, including resistance and numerous adverse effects. Ginseng has been reported to be effective for treating viral infections such as influenza and human immunodeficiency virus. However, there are currently few studies on the effects of ginseng in chronic hepatitis B. Thus, this study investigated the effects of ginseng together with antiviral agents in chronic hepatitis B. This was a prospective, single-blinded, randomized controlled trial, and single-center study. Thirty-eight patients were enrolled. The control group (n = 19) was administered antiviral agents alone. The experimental group (n = 19) was administered antiviral agents along with Korean Red Ginseng powder capsules (each dose is 1 gram (two capsules), a one-day dose is 3 grams). The baseline characteristics did not differ between the two groups. Differences in several non-invasive fibrosis serologic markers (type IV collagen, hyaluronic acid, transforming growth factor-β) and in the hepatitis B virus DNA levels were compared between the groups. The non-invasive fibrosis serologic markers were further decreased in the experimental group, with significant differences after treatment observed for hyaluronic acid (p = 0.032) and transforming growth factor-β (p = 0.008), but not for type IV collagen (p = 0.174). This study suggests the possibility of Korean Red Ginseng as a complementary therapy for chronic hepatitis B.

MicroRNA-466l inhibits antiviral innate immune response by targeting interferon-alpha

PubMed Central

Li, Yingke; Fan, Xiaohua; He, Xingying; Sun, Haijing; Zou, Zui; Yuan, Hongbin; Xu, Haitao; Wang, Chengcai; Shi, Xueyin

2012-01-01

Effective recognition of viral infections and subsequent triggering of antiviral innate immune responses are essential for the host antiviral defense, which is tightly regulated by multiple regulators, including microRNAs (miRNAs). A previous study showed that miR-466l upregulates IL-10 expression in macrophages by antagonizing RNA-binding protein tristetraprolin-mediated IL-10 mRNA degradation. However, the ability of miR-466l to regulate antiviral immune responses remains unknown. Here, we found that interferon-alpha (IFN-α) expression was repressed in Sendai virus (SeV)- and vesicular stomatitis virus (VSV)-infected macrophages and in dendritic cells transfected with miR-466l expression. Moreover, multiple IFN-α species can be directly targeted by miR-466l through their 3′ untranslated region (3′UTR). This study has demonstrated that miR-466l could directly target IFN-α expression to inhibit host antiviral innate immune response. PMID:23042536

Selective Targeting of Antiviral and Immunomodulating Agents in the Treatment of Arenavirus Infections

DTIC Science & Technology

1987-10-01

observed with free MTP-PE. In addition to our observations on peritoneal and alveolar macrophages, we also examined the effect of MTP-PE treatment on liver...Ir OIC FILE COPY C2 ILn 00 NM AD _____ N SELECTIVE TARGETING OF ANTIVIRAL AND IMMUNOMODULATING AGENTS IN THE TREATMENT OF ARENAVIRUS INFECTIONS "Kc...Selective Targeting of Antiviral and Immunomodulating Agents in the Treatment of Arenavirus Injections 12. PERSONAL AUTHOR(S) J. David Gangemi 13a. TYPE OF

Impact of adherence on the outcome of antiviral therapy for chronic hepatitis C.

PubMed

Mulhall, Brian P; Younossi, Zobair

2005-01-01

Nearly 4 million people in the United States have evidence of hepatitis C infection (HCV), representing a significant cause of cirrhosis and liver cancer as well a major burden to our healthcare systems and society. Antiviral therapy can successfully eradicate HCV over the long term, potentially reducing the risk of progression and improving patients' quality of life. The currently preferred HCV treatment is a combination of pegylated interferon alfa and ribavirin, which can achieve an overall sustained viral eradication rate of 55%. The duration of this treatment is typically determined by HCV genotype and the patient's early virologic response to the antiviral regimen. Evidence has accumulated over the past few years to indicate that close adherence to the optimal antiviral regimen can enhance sustained virologic response. But optimal treatment outcomes require diligence and careful management of side effects related to combination therapy. Although reducing the dose of pegylated interferon alfa, ribavirin, or both can effectively treat side effects, suboptimal doses of this regimen, especially ribavirin, may negatively affect virologic response. An alternative strategy is to use growth factors to treat cytopenias. This strategy can obviate dose reductions while potentially improving patients' quality of life. Patient support seems especially important early after the initiation of antiviral therapy. Encouraging study findings involving the growth factors, epoetin alfa and darbepoetin alfa, suggest improved anemia and quality of life while maintaining the optimal ribavirin dose. Future work should be aimed at providing stronger evidence for the use of these "supportive products" during anti-HCV therapy. As we strive to develop better treatment options for our HCV patients, the importance of adhering to the treatment regimen continues to play a central role. Effective side effect management is crucial for the success of this treatment because adherence is

Parallel shRNA and CRISPR-Cas9 screens enable antiviral drug target identification.

PubMed

Deans, Richard M; Morgens, David W; Ökesli, Ayşe; Pillay, Sirika; Horlbeck, Max A; Kampmann, Martin; Gilbert, Luke A; Li, Amy; Mateo, Roberto; Smith, Mark; Glenn, Jeffrey S; Carette, Jan E; Khosla, Chaitan; Bassik, Michael C

2016-05-01

Broad-spectrum antiviral drugs targeting host processes could potentially treat a wide range of viruses while reducing the likelihood of emergent resistance. Despite great promise as therapeutics, such drugs remain largely elusive. Here we used parallel genome-wide high-coverage short hairpin RNA (shRNA) and clustered regularly interspaced short palindromic repeats (CRISPR)-Cas9 screens to identify the cellular target and mechanism of action of GSK983, a potent broad-spectrum antiviral with unexplained cytotoxicity. We found that GSK983 blocked cell proliferation and dengue virus replication by inhibiting the pyrimidine biosynthesis enzyme dihydroorotate dehydrogenase (DHODH). Guided by mechanistic insights from both genomic screens, we found that exogenous deoxycytidine markedly reduced GSK983 cytotoxicity but not antiviral activity, providing an attractive new approach to improve the therapeutic window of DHODH inhibitors against RNA viruses. Our results highlight the distinct advantages and limitations of each screening method for identifying drug targets, and demonstrate the utility of parallel knockdown and knockout screens for comprehensive probing of drug activity.

Targeting Innate Immunity for Antiviral Therapy through Small Molecule Agonists of the RLR Pathway

PubMed Central

Pattabhi, Sowmya; Wilkins, Courtney R.; Dong, Ran; Knoll, Megan L.; Posakony, Jeffrey; Kaiser, Shari; Mire, Chad E.; Wang, Myra L.; Ireton, Renee C.; Geisbert, Thomas W.; Bedard, Kristin M.; Iadonato, Shawn P.

2015-01-01

ABSTRACT The cellular response to virus infection is initiated when pathogen recognition receptors (PRR) engage viral pathogen-associated molecular patterns (PAMPs). This process results in induction of downstream signaling pathways that activate the transcription factor interferon regulatory factor 3 (IRF3). IRF3 plays a critical role in antiviral immunity to drive the expression of innate immune response genes, including those encoding antiviral factors, type 1 interferon, and immune modulatory cytokines, that act in concert to restrict virus replication. Thus, small molecule agonists that can promote IRF3 activation and induce innate immune gene expression could serve as antivirals to induce tissue-wide innate immunity for effective control of virus infection. We identified small molecule compounds that activate IRF3 to differentially induce discrete subsets of antiviral genes. We tested a lead compound and derivatives for the ability to suppress infections caused by a broad range of RNA viruses. Compound administration significantly decreased the viral RNA load in cultured cells that were infected with viruses of the family Flaviviridae, including West Nile virus, dengue virus, and hepatitis C virus, as well as viruses of the families Filoviridae (Ebola virus), Orthomyxoviridae (influenza A virus), Arenaviridae (Lassa virus), and Paramyxoviridae (respiratory syncytial virus, Nipah virus) to suppress infectious virus production. Knockdown studies mapped this response to the RIG-I-like receptor pathway. This work identifies a novel class of host-directed immune modulatory molecules that activate IRF3 to promote host antiviral responses to broadly suppress infections caused by RNA viruses of distinct genera. IMPORTANCE Incidences of emerging and reemerging RNA viruses highlight a desperate need for broad-spectrum antiviral agents that can effectively control infections caused by viruses of distinct genera. We identified small molecule compounds that can

Dynamics of an HBV Model with Drug Resistance Under Intermittent Antiviral Therapy

NASA Astrophysics Data System (ADS)

Zhang, Ben-Gong; Tanaka, Gouhei; Aihara, Kazuyuki; Honda, Masao; Kaneko, Shuichi; Chen, Luonan

2015-06-01

This paper studies the dynamics of the hepatitis B virus (HBV) model and the therapy regimens of HBV disease. First, we propose a new mathematical model of HBV with drug resistance, and then analyze its qualitative and dynamical properties. Combining the clinical data and theoretical analysis, we demonstrate that our model is biologically plausible and also computationally viable. Second, we demonstrate that the intermittent antiviral therapy regimen is one of the possible strategies to treat this kind of complex disease. There are two main advantages of this regimen, i.e. it not only may delay the development of drug resistance, but also may reduce the duration of on-treatment time compared with the long-term continuous medication. Moreover, such an intermittent antiviral therapy can reduce the adverse side effects. Our theoretical model and computational results provide qualitative insight into the progression of HBV, and also a possible new therapy for HBV disease.

Genome editing and the next generation of antiviral therapy

PubMed Central

Stone, Daniel; Niyonzima, Nixon

2016-01-01

Engineered endonucleases such as homing endonucleases (HEs), zinc finger nucleases (ZFNs), Tal-effector nucleases (TALENS) and the RNA-guided engineered nucleases (RGENs or CRISPR/Cas9) can target specific DNA sequences for cleavage, and are proving to be valuable tools for gene editing. Recently engineered endonucleases have shown great promise as therapeutics for the treatment of genetic disease and infectious pathogens. In this review, we discuss recent efforts to use the HE, ZFN, TALEN and CRISPR/Cas9 gene-editing platforms as antiviral therapeutics. We also discuss the obstacles facing gene-editing antiviral therapeutics as they are tested in animal models of disease and transition towards human application. PMID:27272125

Resolution of acute hepatitis B-associated aplastic anaemia with antiviral therapy.

PubMed

Hendren, Nicholas; Moore, Joseph; Hofmann, Sandra; Rambally, Siayareh

2017-10-03

A previously healthy 44-year-old woman presented with 3 days of worsening petechial rash, epistaxis and fatigue. Admission labs revealed pancytopenia, low reticulocyte index and elevated liver enzymes. Bone marrow biopsy demonstrated a profoundly hypocellular bone marrow without dysplasia and additional testing demonstrated an acute hepatitis B infection. In the context of an acute hepatitis B infection, elevated liver enzymes and aplastic anaemia, our patient was diagnosed with severe hepatitis-associated aplastic anaemia due to an acute hepatitis B infection. She was initiated on antiviral therapy with tenofovir and briefly received immunosuppressive therapy with a robust sustained improvement in her blood counts. Acute hepatitis B-associated aplastic anaemia is an exceptionally rare presentation of aplastic anaemia. We present acute hepatitis B-associated aplastic anaemia that resolved with antiviral therapy, which to our knowledge is the second such case reported in the literature and the first using tenofovir. © BMJ Publishing Group Ltd (unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Direct-acting Antivirals and Host-targeting Agents against the Hepatitis A Virus

PubMed Central

Kanda, Tatsuo; Nakamoto, Shingo; Wu, Shuang; Nakamura, Masato; Jiang, Xia; Haga, Yuki; Sasaki, Reina; Yokosuka, Osamu

2015-01-01

Hepatitis A virus (HAV) infection is a major cause of acute hepatitis and occasionally leads to acute liver failure in both developing and developed countries. Although effective vaccines for HAV are available, the development of new antivirals against HAV may be important for the control of HAV infection in developed countries where no universal vaccination program against HAV exists, such as Japan. There are two forms of antiviral agents against HAV: direct-acting antivirals (DAAs) and host-targeting agents (HTAs). Studies using small interfering ribonucleic acid (siRNA) have suggested that the HAV internal ribosomal entry site (IRES) is an attractive target for the control of HAV replication and infection. Among the HTAs, amantadine and interferon-lambda 1 (IL-29) inhibit HAV IRES-mediated translation and HAV replication. Janus kinase (JAK) inhibitors inhibit La protein expression, HAV IRES activity, and HAV replication. Based on this review, both DAAs and HTAs may be needed to control effectively HAV infection, and their use should continue to be explored. PMID:26623267

CRISPR-Cas Targeting of Host Genes as an Antiviral Strategy.

PubMed

Chen, Shuliang; Yu, Xiao; Guo, Deyin

2018-01-16

Currently, a new gene editing tool-the Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR) associated (Cas) system-is becoming a promising approach for genetic manipulation at the genomic level. This simple method, originating from the adaptive immune defense system in prokaryotes, has been developed and applied to antiviral research in humans. Based on the characteristics of virus-host interactions and the basic rules of nucleic acid cleavage or gene activation of the CRISPR-Cas system, it can be used to target both the virus genome and host factors to clear viral reservoirs and prohibit virus infection or replication. Here, we summarize recent progress of the CRISPR-Cas technology in editing host genes as an antiviral strategy.

CRISPR-Cas Targeting of Host Genes as an Antiviral Strategy

PubMed Central

Chen, Shuliang; Yu, Xiao; Guo, Deyin

2018-01-01

Currently, a new gene editing tool—the Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR) associated (Cas) system—is becoming a promising approach for genetic manipulation at the genomic level. This simple method, originating from the adaptive immune defense system in prokaryotes, has been developed and applied to antiviral research in humans. Based on the characteristics of virus-host interactions and the basic rules of nucleic acid cleavage or gene activation of the CRISPR-Cas system, it can be used to target both the virus genome and host factors to clear viral reservoirs and prohibit virus infection or replication. Here, we summarize recent progress of the CRISPR-Cas technology in editing host genes as an antiviral strategy. PMID:29337866

The RNA template channel of the RNA-dependent RNA polymerase as a target for development of antiviral therapy of multiple genera within a virus family.

PubMed

van der Linden, Lonneke; Vives-Adrián, Laia; Selisko, Barbara; Ferrer-Orta, Cristina; Liu, Xinran; Lanke, Kjerstin; Ulferts, Rachel; De Palma, Armando M; Tanchis, Federica; Goris, Nesya; Lefebvre, David; De Clercq, Kris; Leyssen, Pieter; Lacroix, Céline; Pürstinger, Gerhard; Coutard, Bruno; Canard, Bruno; Boehr, David D; Arnold, Jamie J; Cameron, Craig E; Verdaguer, Nuria; Neyts, Johan; van Kuppeveld, Frank J M

2015-03-01

The genus Enterovirus of the family Picornaviridae contains many important human pathogens (e.g., poliovirus, coxsackievirus, rhinovirus, and enterovirus 71) for which no antiviral drugs are available. The viral RNA-dependent RNA polymerase is an attractive target for antiviral therapy. Nucleoside-based inhibitors have broad-spectrum activity but often exhibit off-target effects. Most non-nucleoside inhibitors (NNIs) target surface cavities, which are structurally more flexible than the nucleotide-binding pocket, and hence have a more narrow spectrum of activity and are more prone to resistance development. Here, we report a novel NNI, GPC-N114 (2,2'-[(4-chloro-1,2-phenylene)bis(oxy)]bis(5-nitro-benzonitrile)) with broad-spectrum activity against enteroviruses and cardioviruses (another genus in the picornavirus family). Surprisingly, coxsackievirus B3 (CVB3) and poliovirus displayed a high genetic barrier to resistance against GPC-N114. By contrast, EMCV, a cardiovirus, rapidly acquired resistance due to mutations in 3Dpol. In vitro polymerase activity assays showed that GPC-N114 i) inhibited the elongation activity of recombinant CVB3 and EMCV 3Dpol, (ii) had reduced activity against EMCV 3Dpol with the resistance mutations, and (iii) was most efficient in inhibiting 3Dpol when added before the RNA template-primer duplex. Elucidation of a crystal structure of the inhibitor bound to CVB3 3Dpol confirmed the RNA-binding channel as the target for GPC-N114. Docking studies of the compound into the crystal structures of the compound-resistant EMCV 3Dpol mutants suggested that the resistant phenotype is due to subtle changes that interfere with the binding of GPC-N114 but not of the RNA template-primer. In conclusion, this study presents the first NNI that targets the RNA template channel of the picornavirus polymerase and identifies a new pocket that can be used for the design of broad-spectrum inhibitors. Moreover, this study provides important new insight into the

The RNA Template Channel of the RNA-Dependent RNA Polymerase as a Target for Development of Antiviral Therapy of Multiple Genera within a Virus Family

PubMed Central

van der Linden, Lonneke; Vives-Adrián, Laia; Selisko, Barbara; Ferrer-Orta, Cristina; Liu, Xinran; Lanke, Kjerstin; Ulferts, Rachel; De Palma, Armando M.; Tanchis, Federica; Goris, Nesya; Lefebvre, David; De Clercq, Kris; Leyssen, Pieter; Lacroix, Céline; Pürstinger, Gerhard; Coutard, Bruno; Canard, Bruno; Boehr, David D.; Arnold, Jamie J.; Cameron, Craig E.; Verdaguer, Nuria

2015-01-01

The genus Enterovirus of the family Picornaviridae contains many important human pathogens (e.g., poliovirus, coxsackievirus, rhinovirus, and enterovirus 71) for which no antiviral drugs are available. The viral RNA-dependent RNA polymerase is an attractive target for antiviral therapy. Nucleoside-based inhibitors have broad-spectrum activity but often exhibit off-target effects. Most non-nucleoside inhibitors (NNIs) target surface cavities, which are structurally more flexible than the nucleotide-binding pocket, and hence have a more narrow spectrum of activity and are more prone to resistance development. Here, we report a novel NNI, GPC-N114 (2,2'-[(4-chloro-1,2-phenylene)bis(oxy)]bis(5-nitro-benzonitrile)) with broad-spectrum activity against enteroviruses and cardioviruses (another genus in the picornavirus family). Surprisingly, coxsackievirus B3 (CVB3) and poliovirus displayed a high genetic barrier to resistance against GPC-N114. By contrast, EMCV, a cardiovirus, rapidly acquired resistance due to mutations in 3Dpol. In vitro polymerase activity assays showed that GPC-N114 i) inhibited the elongation activity of recombinant CVB3 and EMCV 3Dpol, (ii) had reduced activity against EMCV 3Dpol with the resistance mutations, and (iii) was most efficient in inhibiting 3Dpol when added before the RNA template-primer duplex. Elucidation of a crystal structure of the inhibitor bound to CVB3 3Dpol confirmed the RNA-binding channel as the target for GPC-N114. Docking studies of the compound into the crystal structures of the compound-resistant EMCV 3Dpol mutants suggested that the resistant phenotype is due to subtle changes that interfere with the binding of GPC-N114 but not of the RNA template-primer. In conclusion, this study presents the first NNI that targets the RNA template channel of the picornavirus polymerase and identifies a new pocket that can be used for the design of broad-spectrum inhibitors. Moreover, this study provides important new insight into the

TRIM25 Is Required for the Antiviral Activity of Zinc Finger Antiviral Protein

PubMed Central

Zheng, Xiaojiao; Wang, Xinlu; Tu, Fan; Wang, Qin; Fan, Zusen

2017-01-01

ABSTRACT Zinc finger antiviral protein (ZAP) is a host factor that specifically inhibits the replication of certain viruses by binding to viral mRNAs and repressing the translation and/or promoting the degradation of target mRNA. In addition, ZAP regulates the expression of certain cellular genes. Here, we report that tripartite motif-containing protein 25 (TRIM25), a ubiquitin E3 ligase, is required for the antiviral activity of ZAP. Downregulation of endogenous TRIM25 abolished ZAP's antiviral activity. The E3 ligase activity of TRIM25 is required for this regulation. TRIM25 mediated ZAP ubiquitination, but the ubiquitination of ZAP itself did not seem to be required for its antiviral activity. Downregulation of endogenous ubiquitin or overexpression of the deubiquitinase OTUB1 impaired ZAP's activity. We provide evidence indicating that TRIM25 modulates the target RNA binding activity of ZAP. These results uncover a mechanism by which the antiviral activity of ZAP is regulated. IMPORTANCE ZAP is a host antiviral factor that specifically inhibits the replication of certain viruses, including HIV-1, Sindbis virus, and Ebola virus. ZAP binds directly to target mRNA, and it represses the translation and promotes the degradation of target mRNA. While the mechanisms by which ZAP posttranscriptionally inhibits target RNA expression have been extensively studied, how its antiviral activity is regulated is not very clear. Here, we report that TRIM25, a ubiquitin E3 ligase, is required for the antiviral activity of ZAP. Downregulation of endogenous TRIM25 remarkably abolished ZAP's activity. TRIM25 is required for ZAP optimal binding to target mRNA. These results help us to better understand how the antiviral activity of ZAP is regulated. PMID:28202764

TRIM25 Is Required for the Antiviral Activity of Zinc Finger Antiviral Protein.

PubMed

Zheng, Xiaojiao; Wang, Xinlu; Tu, Fan; Wang, Qin; Fan, Zusen; Gao, Guangxia

2017-05-01

Zinc finger antiviral protein (ZAP) is a host factor that specifically inhibits the replication of certain viruses by binding to viral mRNAs and repressing the translation and/or promoting the degradation of target mRNA. In addition, ZAP regulates the expression of certain cellular genes. Here, we report that tripartite motif-containing protein 25 (TRIM25), a ubiquitin E3 ligase, is required for the antiviral activity of ZAP. Downregulation of endogenous TRIM25 abolished ZAP's antiviral activity. The E3 ligase activity of TRIM25 is required for this regulation. TRIM25 mediated ZAP ubiquitination, but the ubiquitination of ZAP itself did not seem to be required for its antiviral activity. Downregulation of endogenous ubiquitin or overexpression of the deubiquitinase OTUB1 impaired ZAP's activity. We provide evidence indicating that TRIM25 modulates the target RNA binding activity of ZAP. These results uncover a mechanism by which the antiviral activity of ZAP is regulated. IMPORTANCE ZAP is a host antiviral factor that specifically inhibits the replication of certain viruses, including HIV-1, Sindbis virus, and Ebola virus. ZAP binds directly to target mRNA, and it represses the translation and promotes the degradation of target mRNA. While the mechanisms by which ZAP posttranscriptionally inhibits target RNA expression have been extensively studied, how its antiviral activity is regulated is not very clear. Here, we report that TRIM25, a ubiquitin E3 ligase, is required for the antiviral activity of ZAP. Downregulation of endogenous TRIM25 remarkably abolished ZAP's activity. TRIM25 is required for ZAP optimal binding to target mRNA. These results help us to better understand how the antiviral activity of ZAP is regulated. Copyright © 2017 American Society for Microbiology.

The Race To Find Antivirals for Zika Virus

PubMed Central

2017-01-01

ABSTRACT Zika virus (ZIKV), a flavivirus transmitted by mosquitoes, was an almost neglected pathogen until its introduction in the Americas in 2015 and its subsequent explosive spread throughout the continent, where it has infected millions of people. The virus has caused social and sanitary alarm, mainly due to its association with severe neurological disorders (Guillain-Barré syndrome and microcephaly in fetuses and newborns). Nowadays, no specific antiviral therapy against ZIKV is available. However, during the past months, a great effort has been made to search for antiviral candidates using different approaches and methodologies, ranging from testing specific compounds with known antiviral activity to the screening of libraries with hundreds of bioactive molecules. The identified antiviral candidates include drugs targeting viral components as well as cellular ones. Here, an updated review of what has been done in this line is presented. PMID:28348160

Systems Biology-Based Investigation of Cellular Antiviral Drug Targets Identified by Gene-Trap Insertional Mutagenesis.

PubMed

Cheng, Feixiong; Murray, James L; Zhao, Junfei; Sheng, Jinsong; Zhao, Zhongming; Rubin, Donald H

2016-09-01

Viruses require host cellular factors for successful replication. A comprehensive systems-level investigation of the virus-host interactome is critical for understanding the roles of host factors with the end goal of discovering new druggable antiviral targets. Gene-trap insertional mutagenesis is a high-throughput forward genetics approach to randomly disrupt (trap) host genes and discover host genes that are essential for viral replication, but not for host cell survival. In this study, we used libraries of randomly mutagenized cells to discover cellular genes that are essential for the replication of 10 distinct cytotoxic mammalian viruses, 1 gram-negative bacterium, and 5 toxins. We herein reported 712 candidate cellular genes, characterizing distinct topological network and evolutionary signatures, and occupying central hubs in the human interactome. Cell cycle phase-specific network analysis showed that host cell cycle programs played critical roles during viral replication (e.g. MYC and TAF4 regulating G0/1 phase). Moreover, the viral perturbation of host cellular networks reflected disease etiology in that host genes (e.g. CTCF, RHOA, and CDKN1B) identified were frequently essential and significantly associated with Mendelian and orphan diseases, or somatic mutations in cancer. Computational drug repositioning framework via incorporating drug-gene signatures from the Connectivity Map into the virus-host interactome identified 110 putative druggable antiviral targets and prioritized several existing drugs (e.g. ajmaline) that may be potential for antiviral indication (e.g. anti-Ebola). In summary, this work provides a powerful methodology with a tight integration of gene-trap insertional mutagenesis testing and systems biology to identify new antiviral targets and drugs for the development of broadly acting and targeted clinical antiviral therapeutics.

Changes in Liver Volume in Patients with Chronic Hepatitis C Undergoing Antiviral Therapy.

PubMed

Fitzpatrick, Julie A; Kim, Jin Un; Cobbold, Jeremy F L; McPhail, Mark J W; Crossey, Mary M E; Bak-Bol, Aluel A; Zaky, Ashraf; Taylor-Robinson, Simon D

2016-03-01

Liver volumetric analysis has not been used to detect hepatic remodelling during antiviral therapy before. We measured liver volume (LV) changes on volumetric magnetic resonance imaging during hepatitis C antiviral therapy. 22 biopsy-staged patients (median [range] age 45(19-65) years; 9F, 13M) with chronic hepatitis C virus infection were studied. LV was measured at the beginning, end of treatment and 6 months post-treatment using 3D T1-weighted acquisition, normalised to patient weight. Liver outlines were drawn manually on 4 mm thick image slices and LV calculated. Inter-observer agreement was analysed. Patients were also assessed longitudinally using biochemical parameters and liver stiffness using Fibroscan™. Sustained viral response (SVR) was achieved in 13 patients with a mean baseline LV/kg of 0.022 (SD 0.004) L/kg. At the end of treatment, the mean LV/kg was 0.025 (SD 0.004, P = 0.024 cf baseline LV/kg) and 0.026 (SD 0.004, P = 0.008 cf baseline LV/kg) 6 months post-treatment (P = 0.030 cf baseline, P = 0.004). Body weight-corrected end of treatment LV change was significantly higher in patients with SVR compared to patients not attaining SVR (P = 0.050). End of treatment LV change was correlated to initial ALT (R (2) = 0.479, P = 0.037), but not APRI, AST, viral load or liver stiffness measurements. There was a correlation of 0.89 between observers for measured slice thickness. LV increased during anti-viral treatment, while the body weight-corrected LV increase persisted post-antiviral therapy and was larger in patients with SVR.

Cost-effectiveness analysis of antiviral therapy in patients with advanced hepatitis B virus-related hepatocellular carcinoma treated with sorafenib.

PubMed

Zhang, Pengfei; Yang, Yu; Wen, Feng; Wheeler, John; Fu, Ping; Li, Qiu

2016-12-01

Antiviral therapy has been demonstrated to significantly improve the survival in patients with advanced hepatitis B virus (HBV)-related hepatocellular carcinoma (HCC). The aim of the study was to investigate the cost-effectiveness of antiviral therapy in patients with advanced HBV-related HCC treated with sorafenib. To conduct the analysis, a Markov model comprising three health states (progression-free survival, progressive disease, and death) was created. The efficacy data were derived from medical records. Cost data were collected based on the Chinese national drug prices. Utility data came from the previously published studies. One-way sensitivity analyses as well as probabilistic sensitivity analyses were performed to explore model uncertainties. In the base-case analysis, addition of antiviral therapy to sorafenib generated an effectiveness of 0.68 quality-adjusted life years (QALYs) at a cost of $25 026.04, while sorafenib monotherapy gained an effectiveness of 0.42 QALYs at a cost of $20 249.64. The incremental cost-effectiveness ratio (ICER) was $18 370.77/QALY for antiviral therapy group versus non-antiviral therapy group. On the other hand, the ICER between the two groups in patients with high or low HBV-DNA load, with or without cirrhosis, normal or elevated alanine aminotransferase/aspartate aminotransferase were $16 613.97/QALY, $19 774.16/QALY, $14 587.66/QALY, $19 873.84/QALY, $17 947.07/QALY, and $18 785.58/QALY, respectively. Based on the cost-effectiveness threshold ($20 301.00/QALY in China), addition of antiviral therapy to sorafenib is considered to be a cost-effective option compared with sorafenib monotherapy in patients with advanced HBV-related HCC in China from the patient's perspective. © 2016 Journal of Gastroenterology and Hepatology Foundation and John Wiley & Sons Australia, Ltd.

Anti-viral therapy is associated with improved survival but is underutilised in patients with hepatitis B virus-related hepatocellular carcinoma: real-world east and west experience.

PubMed

Chen, V L; Yeh, M-L; Le, A K; Jun, M; Saeed, W K; Yang, J D; Huang, C-F; Lee, H Y; Tsai, P-C; Lee, M-H; Giama, N; Kim, N G; Nguyen, P P; Dang, H; Ali, H A; Zhang, N; Huang, J-F; Dai, C-Y; Chuang, W-L; Roberts, L R; Jun, D W; Lim, Y-S; Yu, M-L; Nguyen, M H

2018-07-01

Hepatitis B virus (HBV) is the leading cause of hepatocellular carcinoma (HCC) worldwide. It remains incompletely understood in the real world how anti-viral therapy affects survival after HCC diagnosis. This was an international multicentre cohort study of 2518 HBV-related HCC cases diagnosed between 2000 and 2015. Cox proportional hazards models were utilised to estimate hazard ratios (HR) with 95% (CI) for anti-viral therapy and cirrhosis on patients' risk of death. Approximately, 48% of patients received anti-viral therapy at any time, but only 17% were on therapy at HCC diagnosis (38% at US centres, 11% at Asian centres). Anti-viral therapy would have been indicated for >60% of the patients not on anti-viral therapy based on American criteria. Patients with cirrhosis had lower 5-year survival (34% vs 46%; P < 0.001) while patients receiving anti-viral therapy had increased 5-year survival compared to untreated patients (42% vs 25% with cirrhosis and 58% vs 36% without cirrhosis; P < 0.001 for both). Similar findings were seen for other patient subgroups by cancer stages and cancer treatment types. Anti-viral therapy was associated with a decrease in risk of death, whether started before or after HCC diagnosis (adjusted HR 0.62 and 0.79, respectively; P < 0.001). Anti-viral therapy improved overall survival in patients with HBV-related HCC across cancer stages and treatment types but was underutilised at both US and Asia centres. Expanded use of anti-viral therapy in HBV-related HCC and better linkage-to-care for HBV patients are needed. © 2018 John Wiley & Sons Ltd.

HAUS8 regulates RLR‑VISA antiviral signaling positively by targeting VISA.

PubMed

He, Tian-Sheng; Chen, Tian; Wang, Dan-Dan; Xu, Liang-Guo

2018-06-15

Mitochondrial anti‑viral signaling protein (VISA), additionally termed MAVS, IPS‑1 and Cardif, is located at the outer membrane of mitochondria and is an essential adaptor in the Rig‑like receptor (RLRs) signaling pathway. Upon viral infection, activated RLRs interact with VISA on mitochondria, forming a RLR‑VISA platform, leading to the recruitment of different TRAF family members, including TRAF3, TRAF2 and TRAF6. This results in the phosphorylation and nuclear translocation of interferon regulatory factors 3 and 7 (IRF3/IRF7) by TANK binding kinase 1 (TBK1) and/or IKKε, as well as activation of NF‑κB, to induce type I interferons (IFNs) and pro‑inflammatory cytokines. It remains to be elucidated how VISA functions as a scaffold for protein complex assembly in mitochondria to regulate RLR‑VISA antiviral signaling. In the present study, it was demonstrated that HAUS augmin like complex subunit 8 (HAUS8) augments the RLR‑VISA‑dependent antiviral signaling pathway by targeting the VISA complex. Co‑immunoprecipitation verified that HAUS8 was associated with VISA and the VISA signaling complex components retinoic acid‑inducible gene I (RIG‑I) and TBK1 when the RLR‑VISA signaling pathway was activated. The data demonstrated that overexpression of HAUS8 significantly promoted the activity of the transcription factors NF‑κB, IRF3 and the IFN‑β promoter induced by Sendai virus‑mediated RLR‑VISA signaling. HAUS8 increased the polyubiquitination of VISA, RIG‑I and TBK1. Knockdown of HAUS8 inhibited the activation of the transcription factors IRF‑3, NF‑κB and the IFN‑β promoter triggered by Sendai virus. Collectively, these results demonstrated that HAUS8 may function as a positive regulator of RLR‑VISA dependent antiviral signaling by targeting the VISA complex, providing a novel regulatory mechanism of antiviral responses.

Changes in Liver Volume in Patients with Chronic Hepatitis C Undergoing Antiviral Therapy

PubMed Central

Fitzpatrick, Julie A.; Kim, Jin Un; Cobbold, Jeremy F.L.; McPhail, Mark J.W.; Crossey, Mary M.E.; Bak-Bol, Aluel A.; Zaky, Ashraf; Taylor-Robinson, Simon D.

2016-01-01

Aim Liver volumetric analysis has not been used to detect hepatic remodelling during antiviral therapy before. We measured liver volume (LV) changes on volumetric magnetic resonance imaging during hepatitis C antiviral therapy. Methods 22 biopsy-staged patients (median [range] age 4519–65 years; 9F, 13M) with chronic hepatitis C virus infection were studied. LV was measured at the beginning, end of treatment and 6 months post-treatment using 3D T1-weighted acquisition, normalised to patient weight. Liver outlines were drawn manually on 4 mm thick image slices and LV calculated. Inter-observer agreement was analysed. Patients were also assessed longitudinally using biochemical parameters and liver stiffness using Fibroscan™. Results Sustained viral response (SVR) was achieved in 13 patients with a mean baseline LV/kg of 0.022 (SD 0.004) L/kg. At the end of treatment, the mean LV/kg was 0.025 (SD 0.004, P = 0.024 cf baseline LV/kg) and 0.026 (SD 0.004, P = 0.008 cf baseline LV/kg) 6 months post-treatment (P = 0.030 cf baseline, P = 0.004). Body weight-corrected end of treatment LV change was significantly higher in patients with SVR compared to patients not attaining SVR (P = 0.050). End of treatment LV change was correlated to initial ALT (R2 = 0.479, P = 0.037), but not APRI, AST, viral load or liver stiffness measurements. There was a correlation of 0.89 between observers for measured slice thickness. Conclusions LV increased during anti-viral treatment, while the body weight-corrected LV increase persisted post-antiviral therapy and was larger in patients with SVR. PMID:27194891

Clinical features and effect of antiviral therapy on anti-liver/kidney microsomal antibody type 1 positive chronic hepatitis C.

PubMed

Ferri, Silvia; Muratori, Luigi; Quarneti, Chiara; Muratori, Paolo; Menichella, Rita; Pappas, Georgios; Granito, Alessandro; Ballardini, Giorgio; Bianchi, Francesco B; Lenzi, Marco

2009-06-01

Anti-liver/kidney microsomal antibody type 1 (anti-LKM1), a serological marker of type 2 autoimmune hepatitis, is also detected in a small proportion of patients with hepatitis C. This study aimed to evaluate clinical features and effect of antiviral therapy in patients with hepatitis C who are anti-LKM1 positive. Sixty consecutive anti-LKM1 positive and 120 age and sex-matched anti-LKM1 negative chronic hepatitis C patients were assessed at diagnosis and during follow-up. Of these, 26 anti-LKM1 positive and 72 anti-LKM1 negative received antiviral therapy. Anti-LKM1 was detected by indirect immunofluorescence and immunoblot. Number of HCV-infected hepatocytes and intrahepatic CD8+ lymphocytes was determined by immunohistochemistry. At diagnosis anti-LKM1 positive patients had higher IgG levels and more intrahepatic CD8+ lymphocytes (p 0.022 and 0.046, respectively). Viral genotypes distribution and response to therapy were identical. Hepatic flares during antiviral treatment only occurred in a minority of patients in concomitance with anti-LKM1 positivity. Immune system activation is more pronounced in anti-LKM1 positive patients with hepatitis C, possibly representing the expression of autoimmune mechanisms of liver damage. Antiviral treatment is as beneficial in these patients as in anti-LKM1 negative patients, and the rare necroinflammatory flares are effectively controlled by corticosteroids, allowing subsequent resumption of antiviral therapy.

Unfavorable outcome of antiviral therapy in cytomegalovirus-positive ulcerative colitis may be due to inappropriate study inclusion in meta-analysis.

PubMed

Wu, Xiao-Wei; Yang, Miao-Fang; Li, Nan; Wang, Fang-Yu

2015-02-07

Some previous articles reported that antiviral treatment was effective to reduce the colectomy rate in ulcerative colitis (UC) patients with cytomegalovirus (CMV) infection. Kopylov et al recently carried out a systematic review and meta-analysis to evaluate the impact of antiviral therapy on CMV-positive UC. The results showed that patients who received antiviral treatment had a higher risk of 30-d colectomy. We found that in this meta-analysis, some studies were inappropriately included, leading to an unfavorable outcome of anti-CMV therapy in UC patients.

[Analysis of the cost-effectiveness of antiviral therapies in chronic hepatitis B patients in Korea].

PubMed

Kim, Byung Kook; Kwon, So Young; Lee, Chang Hong; Choe, Won Hyeok; Choi, Hong Mi; Koo, Hye Won

2009-03-01

The purpose of this study was to evaluate the cost-effectiveness of 1 year and up to 5 years of antiviral treatment for chronic hepatitis B (CHB). Two ten-health-state Markov models were developed for CHB patients. The proportion of patients remaining alive in each health state, and healthcare costs and quality-adjusted life years (QALYs) were determined during annual cycles of these Markov models. The total healthcare costs, life years, and QALYs over the 40-year time horizon of the model were calculated. The perspectives of the cost-effectiveness analysis were the Korean healthcare system and the healthcare needs of the CHB patient. Short-course therapy with alpha-interferon or 1-year treatment with pegylated interferon alpha-2a, lamivudine (LMV), or adefovir (ADV) had limited impact on disease progression. In contrast, either LMV-ADV or ADV-LMV as rescue medication administered for 5 years resulted in a more sustained decrease in the rate of disease progression. The cost-effectiveness threshold in Korea was estimated to be approximately 25,000,000 South Korean won. LMV administered for 1 year is cost-effective in comparison with no treatment for both HBeAg-positive and HBeAg-negative CHB patients, but longer duration antiviral therapies administered for up to 5 years in CHB patients were found to be highly cost-effective by international standards. Antiviral treatment of CHB with LMV or ADV for up to 5 years using the alternative antiviral agent as rescue medication appears to be a cost-effective strategy for both HBeAg-positive and HBeAg-negative CHB patients in Korea. Economic evaluation of antiviral therapies should be studied further and updated, particularly for newer agents.

Effects of transarterial chemoembolization combined with antiviral therapy on HBV reactivation and liver function in HBV-related hepatocellular carcinoma patients with HBV-DNA negative.

PubMed

Wang, Kai; Jiang, Guomin; Jia, Zhongzhi; Zhu, Xiaoli; Ni, Caifang

2018-06-01

The aim of this study was to investigate the reactivation of the hepatitis B virus (HBV) following transarterial chemoembolization (TACE) in primary hepatocellular carcinoma (HCC) patients with HBV-DNA negative and to evaluate the effects of TACE combined with antiviral therapy. This prospective study involved 98 patients with HBV-related and HBV-DNA negative HCC (HBV DNA < 10 copies/mL) underwent TACE procedures with serial HBV DNA tests. Patients were divided into the antiviral treatment group and the no-antiviral group. The antiviral group received entecavir antiviral therapy, and the other group received no antiviral therapy. Two groups of patients were compared in rate of HBV reactivation and liver function before and after only 1 session of TACE in average 1-month follow-up after operation. P < .05 indicated differences with a statistical significance. HBV reactivation occurred in 11 patients in the nonantiviral group (11/47, 23.4%) but only 3 patients in the antiviral group (3/51, 5.9%, P < .05). On multivariate analysis, HBeAg-positive status, number of tumors more than 3, and absence of antiviral therapy were the independent risk predictor of HBV reactivation. Liver function indicators did not differ significantly between the antiviral group and the nonantiviral group in 5 days after TACE. However, the level of alanine aminotransferase and bilirubin were raised and albumin was reduced at the HBV reactivation group compared with no HBV reactivation group (P < .05). At 1 month after TACE, liver function indicators did not differ significantly between the HBV reactivation group and without HBV reactivation group. HCC patients with HBV DNA negative still remain associated with risk of HBV reactivation after TACE. HBeAg-positive, number of tumors more than 3, and absence of antiviral therapy in HCC patients after TACE have a higher risk of HBV reactivation. Antiviral therapy can reduce the risk of reactivation, helping improve liver function

Liver toxicity of chemotherapy and targeted therapy for breast cancer patients with hepatitis virus infection.

PubMed

Liu, Yu; Li, Zhan-Yi; Li, Xi; Wang, Jia-Ni; Huang, Qun-Ai; Huang, Yong

2017-10-01

Chemotherapy has greatly improved the prognosis of breast cancer patients. However, it may also result in undesirable side effects such as hepatitis virus reactivation. Little information is available on the liver toxicity of chemotherapy and targeted therapy for breast cancer patients with hepatitis virus (HBV/HCV) infection. We performed a retrospective survey of 835 patients diagnosed with breast cancer between January 2010 and December 2015 at our institution. All patients had been screened for HBV/HCV infection at the time of breast cancer diagnosis. We retrospectively investigated the toxicity of chemotherapy and the changes in HBV/HCV load based on a medical record review. 52 patients with positive anti-HBV antibody test and 21 patients with positive anti-HCV antibody tests received chemotherapy. 762 patients without HBV and HCV infection served as the control group. The morbidity of liver toxicity and disruptions in chemotherapy attributable to liver toxicity were not significantly different among control group, HBV group and HCV groups (27.7% vs 34.6% vs 42.9%, P = 0.189 and 5.0% vs 9.6% vs 9.5%, P = 0.173, respectively). No patients presented with HBV/HCV reactivation. Breast cancer patients with HCV can be treated with chemotherapy and targeted therapy with trastuzumab. Breast cancer patients with HBV who accept antiviral therapy can be treated with chemotherapy and targeted therapy with trastuzumab and patients can benefit from prophylactic antiviral therapy before chemotherapy. However, a multidisciplinary cooperation and closely monitoring liver function during the course of chemotherapy may benefit patients. Copyright © 2017 Elsevier Ltd. All rights reserved.

Antiviral therapy for HCV-associated cryoglobulinemic glomerulonephritis: case report and review of the literature.

PubMed

Fabrizi, Fabrizio; Fogazzi, Giovanni Battista; Cresseri, Donata; Passerini, Patrizia; Martin, Paul; Donato, Maria Francesca; Rumi, Maria Grazia; Messa, Piergiorgio

2012-01-01

We describe the case of a 51-year-old woman with HCV-associated cryoglobulinemic glomerulonephritis (GN). She presented mild deterioration of kidney function, non-nephrotic proteinuria, and active urinary sediment. Kidney biopsy showed features of membranoproliferative changes with some sclerosis. Sustained viral response (SVR) was obtained by 6 months of antiviral therapy (peg-IFN-α2a plus ribavirin). SVR was linked with improvement of kidney function and remission of proteinuria. Clinical and virological remission persists over a 25-month follow-up. This case report emphasizes efficacy and safety of antiviral treatment of HCV-associated glomerulonephritis--preliminary but encouraging results exist. We identified by systematic review of the literature 9 studies (156 unique patients); the pooled estimate of frequency of sustained virological response after IFN-based therapy was 0.49 (95% confidence interval, CI: 0.21, 0.77; p < 0.0005; random effects model). Heterogeneity was found (I(2) = 98.9%, p < 0.0001). Two possible regimens should be considered for the treatment of HCV-associated cryoglobulinemic GN according to the clinical presentation. Immunosuppressive therapy is recommended for HCV-related kidney disease having aggressive course, and recent evidence supports rituximab (RTX) use with a reduced exposure to corticosteroids. We identified six studies (66 unique patients) on RTX therapy for HCV-associated kidney disease; at the end of RTX therapy, the pooled estimate of the mean decrease in proteinuria was 1.4 g/24 h (95% CI: 0.75, 2.05, p < 0.001); The p test for heterogeneity gave a value of 0.94 (I(2) = 0). Several questions related to RTX use remain. HCV-induced GN is uncommon among CKD patients of developed countries, and this clearly hampers prospective controlled clinical trials aimed to evaluate efficacy and safety of antiviral or immunosuppressive therapy in this population. Copyright © 2013 S. Karger AG, Basel.

Newer influenza antivirals, biotherapeutics and combinations

PubMed Central

Hayden, Frederick G.

2012-01-01

Please cite this paper as: Hayden FG. (2012) Newer Influenza Antivirals, Biotherapeutics and Combinations. Influenza and Other Respiratory Viruses 7(Suppl. 1), 63–75. This summary provides an overview of investigational antiviral agents for influenza and of future directions for development of influenza therapeutics. While progress in developing clinically useful antiviral agents for influenza has been generally slow, especially with respect to seriously ill and high‐risk patients, important clinical studies of intravenous neuraminidase inhibitors, antibodies and drug combinations are currently in progress. The current decade offers the promise of developing small molecular weight inhibitors with novel mechanisms of action, including host‐directed therapies, new biotherapeutics and drug combinations, that should provide more effective antiviral therapies and help mitigate the problem of antiviral resistance. Immunomodulatory interventions also offer promise but need to be based on better understanding of influenza pathogenesis, particularly in seriously ill patients. The development of combination interventions, immunomodulators and host‐directed therapies presents unique clinical trial design and regulatory hurdles that remain to be addressed. PMID:23279899

A human genome-wide loss-of-function screen identifies effective chikungunya antiviral drugs

PubMed Central

Karlas, Alexander; Berre, Stefano; Couderc, Thérèse; Varjak, Margus; Braun, Peter; Meyer, Michael; Gangneux, Nicolas; Karo-Astover, Liis; Weege, Friderike; Raftery, Martin; Schönrich, Günther; Klemm, Uwe; Wurzlbauer, Anne; Bracher, Franz; Merits, Andres; Meyer, Thomas F.; Lecuit, Marc

2016-01-01

Chikungunya virus (CHIKV) is a globally spreading alphavirus against which there is no commercially available vaccine or therapy. Here we use a genome-wide siRNA screen to identify 156 proviral and 41 antiviral host factors affecting CHIKV replication. We analyse the cellular pathways in which human proviral genes are involved and identify druggable targets. Twenty-one small-molecule inhibitors, some of which are FDA approved, targeting six proviral factors or pathways, have high antiviral activity in vitro, with low toxicity. Three identified inhibitors have prophylactic antiviral effects in mouse models of chikungunya infection. Two of them, the calmodulin inhibitor pimozide and the fatty acid synthesis inhibitor TOFA, have a therapeutic effect in vivo when combined. These results demonstrate the value of loss-of-function screening and pathway analysis for the rational identification of small molecules with therapeutic potential and pave the way for the development of new, host-directed, antiviral agents. PMID:27177310

A human genome-wide loss-of-function screen identifies effective chikungunya antiviral drugs.

PubMed

Karlas, Alexander; Berre, Stefano; Couderc, Thérèse; Varjak, Margus; Braun, Peter; Meyer, Michael; Gangneux, Nicolas; Karo-Astover, Liis; Weege, Friderike; Raftery, Martin; Schönrich, Günther; Klemm, Uwe; Wurzlbauer, Anne; Bracher, Franz; Merits, Andres; Meyer, Thomas F; Lecuit, Marc

2016-05-12

Chikungunya virus (CHIKV) is a globally spreading alphavirus against which there is no commercially available vaccine or therapy. Here we use a genome-wide siRNA screen to identify 156 proviral and 41 antiviral host factors affecting CHIKV replication. We analyse the cellular pathways in which human proviral genes are involved and identify druggable targets. Twenty-one small-molecule inhibitors, some of which are FDA approved, targeting six proviral factors or pathways, have high antiviral activity in vitro, with low toxicity. Three identified inhibitors have prophylactic antiviral effects in mouse models of chikungunya infection. Two of them, the calmodulin inhibitor pimozide and the fatty acid synthesis inhibitor TOFA, have a therapeutic effect in vivo when combined. These results demonstrate the value of loss-of-function screening and pathway analysis for the rational identification of small molecules with therapeutic potential and pave the way for the development of new, host-directed, antiviral agents.

Antiviral therapy of hepatitis C in 2014: do we need resistance testing?

PubMed

Schneider, Maximilian David; Sarrazin, Christoph

2014-05-01

The treatment of chronic hepatitis C has fundamentally changed since the approval of the first direct-acting antivirals (DAA) in 2011. In addition to telaprevir and boceprevir, in 2014 two new NS3 protease inhibitors (simeprevir and faldaprevir), one non-nucleoside polymerase inhibitor (sofosbuvir) and one NS5a replication complex inhibitor (daclatasvir) have expanded the treatment options for chronic hepatitis C. Resistance-associated variants (RAV) are naturally produced during the HCV life cycle. The frequency of RAVs within HCV quasispecies mainly depends on their replicational fitness. Variants conferring resistance to nucleos(t)ide analogues have not been detected, and the majority of NS3 protease-resistant variants are present at low frequencies (0.1-3%) before initiation of DAA-based therapies. However, the Q80K variant conferring resistance to simeprevir has been observed in 9-48% of untreated HCV genotype 1a-infected patients, leading to reduced SVR rates. Resistant variants are detectable in the majority of patients with treatment failure to NS3 protease inhibitor- or NS5a inhibitor-based antiviral therapy. Long-term follow-up studies by population-based sequence analysis have shown the disappearance of resistant variants in the majority of patients, with median times to loss of mutations of 4-64weeks. For the nucleotide analogue sofosbuvir, the emergence of the S282T resistant variant has been observed only in single patients, with reversion to wild-type within several weeks. Data are sparse on retreatment of patients with the same DAA or the same class of DAAs. However, retreatment with a different class of DAAs after failure of NS3 protease inhibitor-based therapy has been successful in small studies. This article forms part of a symposium in Antiviral Research on "Hepatitis C: next steps toward global eradication." Copyright © 2014 Elsevier B.V. All rights reserved.

Newer influenza antivirals, biotherapeutics and combinations.

PubMed

Hayden, Frederick G

2013-01-01

This summary provides an overview of investigational antiviral agents for influenza and of future directions for development of influenza therapeutics. While progress in developing clinically useful antiviral agents for influenza has been generally slow, especially with respect to seriously ill and high-risk patients, important clinical studies of intravenous neuraminidase inhibitors, antibodies and drug combinations are currently in progress. The current decade offers the promise of developing small molecular weight inhibitors with novel mechanisms of action, including host-directed therapies, new biotherapeutics and drug combinations, that should provide more effective antiviral therapies and help mitigate the problem of antiviral resistance. Immunomodulatory interventions also offer promise but need to be based on better understanding of influenza pathogenesis, particularly in seriously ill patients. The development of combination interventions, immunomodulators and host-directed therapies presents unique clinical trial design and regulatory hurdles that remain to be addressed. © 2012 Blackwell Publishing Ltd.

Antiviral therapy after non-surgical tumor ablation in patients with hepatocellular carcinoma associated with hepatitis C virus.

PubMed

Hung, Chao-Hung; Lee, Chuan-Mo; Wang, Jing-Houng; Tung, Hung-Da; Chen, Chien-Hung; Lu, Sheng-Nan

2005-10-01

Antiviral therapy for chronic hepatitis C virus (HCV) infection has led to a reduction in the incidence of hepatocellular carcinoma (HCC). The purpose of the present paper was to assess whether antiviral therapy might suppress tumor recurrence and influence overall survival in patients with HCV-related HCC who had complete ablation of nodules by non-surgical treatments. Twenty patients with three or fewer nodules of HCV-related HCC who were treated with percutaneous tumor ablation and/or transcatheter arterial embolization received combined interferon (IFN; 3 or 5 million units of IFN alpha-2b thrice weekly) plus ribavirin (1000-1200 mg per day) therapy for 24-48 weeks after complete ablation of lesions. During the same period, an additional 40 age- and sex-matched control patients with similar characteristics of tumors (sizes, numbers and treatment modalities) and severity of liver disease were recruited from the HCC database. Both recurrence-free survival and actuarial survival were evaluated. Of the 20 patients, 16 completed therapy and 10 showed a sustained response with normalization of alanine aminotransferase and negative HCV-RNA at 6 months after therapy completion. Due to severe side-effects experienced by Child B patients, who mostly discontinued antiviral therapy, clinical outcome was analyzed in the Child A treated (n = 16) and control (n = 33) patients. There was no significant difference in the incidence of local recurrence in sustained responders compared with non-responders or control patients (P = 0.174, 0.1284, respectively); but the second recurrence-free interval in the sustained responders was significantly longer than that of non-responders and the control group (P = 0.0141, 0.0243, respectively). Survival in sustained responders was better than in non-responders and control patients (P = 0.0691, 0.0554, respectively). These results indicate that successful antiviral therapy after non-surgical tumor ablation for HCV-related HCC may lower tumor

Antiviral therapy: a perspective.

PubMed

Shahidi Bonjar, Amir Hashem

2016-01-01

research has yielded positive results in animal models, EVAC could be used as a supportive treatment in humans along with conventional antiviral therapies. EVAC would not be suitable for all viral infections, but could be expected to decrease the casualties resulting from blood-borne viral infections. The EVAC approach would be efficient in terms of time, effort, and expenditure in the research and treatment of blood-borne viral infections.

Virus-encoded chemokine receptors--putative novel antiviral drug targets.

PubMed

Rosenkilde, Mette M

2005-01-01

Large DNA viruses, in particular herpes- and poxviruses, have evolved proteins that serve as mimics or decoys for endogenous proteins in the host. The chemokines and their receptors serve key functions in both innate and adaptive immunity through control of leukocyte trafficking, and have as such a paramount role in the antiviral immune responses. It is therefore not surprising that viruses have found ways to exploit and subvert the chemokine system by means of molecular mimicry. By ancient acts of molecular piracy and by induction and suppression of endogenous genes, viruses have utilized chemokines and their receptors to serve a variety of roles in viral life-cycle. This review focuses on the pharmacology of virus-encoded chemokine receptors, yet also the family of virus-encoded chemokines and chemokine-binding proteins will be touched upon. Key properties of the virus-encoded receptors, compared to their closest endogenous homologs, are interactions with a wider range of chemokines, which can act as agonists, antagonists and inverse agonists, and the exploitation of many signal transduction pathways. High constitutive activity is another key property of some--but not all--of these receptors. The chemokine receptors belong to the superfamily of G-protein coupled 7TM receptors that per se are excellent drug targets. At present, non-peptide antagonists have been developed against many chemokine receptors. The potentials of the virus-encoded chemokine receptors as drug targets--ie. as novel antiviral strategies--will be highlighted here together with the potentials of the virus-encoded chemokines and chemokine-binding proteins as novel anti-inflammatory biopharmaceutical strategies.

Clinical Laboratory Testing in the Era of Directly Acting Antiviral Therapies for Hepatitis C

PubMed Central

Wilson, Eleanor M.; Rosenthal, Elana S.; Kattakuzhy, Sarah; Tang, Lydia

2016-01-01

SUMMARY Directly acting antiviral (DAA) combination therapies for chronic hepatitis C virus (HCV) infection are highly effective, but treatment decisions remain complex. Laboratory testing is important to evaluate a range of viral, host, and pharmacological factors when considering HCV treatment, and patients must be monitored during and after therapy for safety and to assess the viral response. In this review, we discuss the laboratory tests relevant for the treatment of HCV infection in the era of DAA therapy, grouped according to viral and host factors. PMID:27795306

Clearance of hepatitis C viral RNA in cirrhotic patients with antiviral therapy.

PubMed

Ono, S K; da Silva, L C; Carrilho, F J; da Fonseca, L E; Mendes, L C; Madruga, C L; Farias, A de Q; Laudanna, A A

1996-01-01

Interferon is indicated in chronic infection by hepatitis C virus (HCV), however, cirrhosis has been reported as a bad response factor to the therapy. Fifteen cirrhotic patients with HCV, undergoing treatment with recombinant interferon-alpha, ribavirin and/or ursodeoxycholic acid were studied. They were followed-up and evaluated with dosages of alanine aminotransferase and HCV RNA investigation by PCR technique. Of the 15 cirrhotic patients, seven were negative for HCV RNA after antiviral treatment, however ALT was normal in only three of them. Of the eight patients who were not negative, two had normal ALT. Biochemical-virological discrepancy in the follow-up of the patients after antiviral treatment observed in this study has also been reported by other authors. These reports show that the criteria for response to the treatment is to be established.

Broad-spectrum antivirals against viral fusion

PubMed Central

Vigant, Frederic; Santos, Nuno C.; Lee, Benhur

2015-01-01

Effective antivirals have been developed against specific viruses, such as HIV, Hepatitis C virus and influenza virus. This ‘one bug–one drug’ approach to antiviral drug development can be successful, but it may be inadequate for responding to an increasing diversity of viruses that cause significant diseases in humans. The majority of viral pathogens that cause emerging and re-emerging infectious diseases are membrane-enveloped viruses, which require the fusion of viral and cell membranes for virus entry. Therefore, antivirals that target the membrane fusion process represent new paradigms for broad-spectrum antiviral discovery. In this Review, we discuss the mechanisms responsible for the fusion between virus and cell membranes and explore how broad-spectrum antivirals target this process to prevent virus entry. PMID:26075364

IRF-4 and c-Rel expression in antiviral-resistant adult T-cell leukemia/lymphoma

PubMed Central

Ramos, Juan Carlos; Ruiz, Phillip; Ratner, Lee; Reis, Isildinha M.; Brites, Carlos; Pedroso, Celia; Byrne, Gerald E.; Toomey, Ngoc L.; Andela, Valentine; Harhaj, Edward W.; Lossos, Izidore S.

2007-01-01

Adult T-cell leukemia/lymphoma (ATLL) is a generally fatal malignancy. Most ATLL patients fare poorly with conventional chemotherapy; however, antiviral therapy with zidovudine (AZT) and interferon alpha (IFN-α) has produced long-term clinical remissions. We studied primary ATLL tumors and identified molecular features linked to sensitivity and resistance to antiviral therapy. Enhanced expression of the proto-oncogene c-Rel was noted in 9 of 27 tumors. Resistant tumors exhibited c-Rel (6 of 10; 60%) more often than did sensitive variants (1 of 9; 11%). This finding was independent of the disease form. Elevated expression of the putative c-Rel target, interferon regulatory factor-4 (IRF-4), was observed in 10 (91%) of 11 nonresponders and in all tested patients with c-Rel+ tumors and occurred in the absence of the HTLV-1 oncoprotein Tax. In contrast, tumors in complete responders did not express c-Rel or IRF-4. Gene rearrangement studies demonstrated the persistence of circulating T-cell clones in long-term survivors maintained on antiviral therapy. The expression of nuclear c-Rel and IRF-4 occurs in the absence of Tax in primary ATLL and is associated with antiviral resistance. These molecular features may help guide treatment. AZT and IFN-α is a suppressive rather than a curative regimen, and patients in clinical remission should remain on maintenance therapy indefinitely. PMID:17138822

Inhibition of HIV replication by pokeweed antiviral protein targeted to CD4+ cells by monoclonal antibodies

NASA Astrophysics Data System (ADS)

Zarling, Joyce M.; Moran, Patricia A.; Haffar, Omar; Sias, Joan; Richman, Douglas D.; Spina, Celsa A.; Myers, Dorothea E.; Kuebelbeck, Virginia; Ledbetter, Jeffrey A.; Uckun, Fatih M.

1990-09-01

FUNCTIONAL impairment and selective depletion of CD4+ T cells, the hallmark of AIDS, are at least partly caused by human immunodeficiency virus (HIV-1) type 1 binding to the CD4 molecule and infecting CD4+ cells1,2. It may, therefore, be of therapeutic value to target an antiviral agent to CD4+ cells to prevent infection and to inhibit HIV-1 production in patients' CD4+ cells which contain proviral DNA3,4. We report here that HIV-1 replication in normal primary CD4+ T cells can be inhibited by pokeweed antiviral protein, a plant protein of relative molecular mass 30,000 (ref. 5), which inhibits replication of certain plant RNA viruses6-8, and of herpes simplex virus, poliovirus and influenza virus9-11. Targeting pokeweed antiviral protein to CD4+ T cells by conjugating it to monoclonal antibodies reactive with CDS, CD7 or CD4 expressed on CD4+ cells, increased its anti-HIV potency up to 1,000-fold. HIV-1 replication is inhibited at picomolar concentrations of conjugates of pokeweed antiviral protein and monoclonal antibodies, which do not inhibit proliferation of normal CD4+ T cells or CD4-dependent responses. These conjugates inhibit HIV-1 protein synthesis and also strongly inhibit HIV-1 production in activated CD4+ T cells from infected patients.

Towards antiviral therapies for treating dengue virus infections.

PubMed

Kaptein, Suzanne Jf; Neyts, Johan

2016-10-01

Dengue virus is an emerging human pathogen that poses a huge public health burden by infecting annually about 390 million individuals of which a quarter report with clinical manifestations. Although progress has been made in understanding dengue pathogenesis, a licensed vaccine or antiviral therapy against this virus is still lacking. Treatment of patients is confined to symptomatic alleviation and supportive care. The development of dengue therapeutics thus remains of utmost importance. This review focuses on the few molecules that were evaluated in dengue virus-infected patients: balapiravir, chloroquine, lovastatin, prednisolone and celgosivir. The lessons learned from these clinical trials can be very helpful for the design of future trials for the next generation of dengue virus inhibitors. Copyright © 2016 Elsevier Ltd. All rights reserved.

Effects of Smoking on Pegylated Interferon alpha 2a and First Generation Protease Inhibitor-based Antiviral Therapy in Naïve Patients Infected with Hepatitis C Virus Genotype 1.

PubMed

Zimmermann, Tim; Hueppe, Dietrich; Mauss, Stefan; Buggisch, Peter; Pfeiffer-Vornkahl, Heike; Grimm, Daniel; Galle, Peter R; Alshuth, Ulrich

2016-03-01

Smoking has multiple effects on factors influencing hepatitis C and antiviral therapy, including lipid metabolism, fibrosis, platelet count and adherence aspects. The aim of this analysis was to determine the impact of smoking on hepatitis C virus antiviral therapy. Data of two cohorts of an observational multicenter study including therapy-naïve patients infected with genotype 1 hepatitis C virus (HCV) treated with dual antiviral therapy (n=7,796) with pegylated interferon alpha 2a in combination with ribavirin, or triple antiviral therapy (n=1,122) containing telaprevir or boceprevir, were analysed. In the univariate matched pair analysis of dual antiviral therapy patients (n=584), smoking was significantly associated with lower sustained viral response rates (p=0.026, OR 0.69 CI: 0.50 - 0.96). The effect of smoking on sustained viral response remained significant (p=0.028, OR 0.67 CI: 0.47 - 0.96) in the multivariate analysis when adjusting for all other baseline parameters with a significant association in the univariate analysis, i.e. diabetes, fibrosis, body mass index, transaminases and baseline viral load. Under protease inhibitors the influence of smoking on virological response did not arise. Smoking has a negative impact on antiviral therapy in naïve patients infected with HCV genotype 1 independently of age, gender, history of drug use or alcoholic liver disease. The effects of smoking might be overcome by the new antiviral agents.

An Interferon Regulated MicroRNA Provides Broad Cell-Intrinsic Antiviral Immunity through Multihit Host-Directed Targeting of the Sterol Pathway

PubMed Central

Robertson, Kevin A.; Hsieh, Wei Yuan; Forster, Thorsten; Blanc, Mathieu; Lu, Hongjin; Crick, Peter J.; Yutuc, Eylan; Watterson, Steven; Martin, Kimberly; Griffiths, Samantha J.; Enright, Anton J.; Yamamoto, Mami; Pradeepa, Madapura M.; Lennox, Kimberly A.; Behlke, Mark A.; Talbot, Simon; Haas, Jürgen; Dölken, Lars; Griffiths, William J.; Wang, Yuqin; Angulo, Ana; Ghazal, Peter

2016-01-01

In invertebrates, small interfering RNAs are at the vanguard of cell-autonomous antiviral immunity. In contrast, antiviral mechanisms initiated by interferon (IFN) signaling predominate in mammals. Whilst mammalian IFN-induced miRNA are known to inhibit specific viruses, it is not known whether host-directed microRNAs, downstream of IFN-signaling, have a role in mediating broad antiviral resistance. By performing an integrative, systematic, global analysis of RNA turnover utilizing 4-thiouridine labeling of newly transcribed RNA and pri/pre-miRNA in IFN-activated macrophages, we identify a new post-transcriptional viral defense mechanism mediated by miR-342-5p. On the basis of ChIP and site-directed promoter mutagenesis experiments, we find the synthesis of miR-342-5p is coupled to the antiviral IFN response via the IFN-induced transcription factor, IRF1. Strikingly, we find miR-342-5p targets mevalonate-sterol biosynthesis using a multihit mechanism suppressing the pathway at different functional levels: transcriptionally via SREBF2, post-transcriptionally via miR-33, and enzymatically via IDI1 and SC4MOL. Mass spectrometry-based lipidomics and enzymatic assays demonstrate the targeting mechanisms reduce intermediate sterol pathway metabolites and total cholesterol in macrophages. These results reveal a previously unrecognized mechanism by which IFN regulates the sterol pathway. The sterol pathway is known to be an integral part of the macrophage IFN antiviral response, and we show that miR-342-5p exerts broad antiviral effects against multiple, unrelated pathogenic viruses such Cytomegalovirus and Influenza A (H1N1). Metabolic rescue experiments confirm the specificity of these effects and demonstrate that unrelated viruses have differential mevalonate and sterol pathway requirements for their replication. This study, therefore, advances the general concept of broad antiviral defense through multihit targeting of a single host pathway. PMID:26938778

An Interferon Regulated MicroRNA Provides Broad Cell-Intrinsic Antiviral Immunity through Multihit Host-Directed Targeting of the Sterol Pathway.

PubMed

Robertson, Kevin A; Hsieh, Wei Yuan; Forster, Thorsten; Blanc, Mathieu; Lu, Hongjin; Crick, Peter J; Yutuc, Eylan; Watterson, Steven; Martin, Kimberly; Griffiths, Samantha J; Enright, Anton J; Yamamoto, Mami; Pradeepa, Madapura M; Lennox, Kimberly A; Behlke, Mark A; Talbot, Simon; Haas, Jürgen; Dölken, Lars; Griffiths, William J; Wang, Yuqin; Angulo, Ana; Ghazal, Peter

2016-03-01

In invertebrates, small interfering RNAs are at the vanguard of cell-autonomous antiviral immunity. In contrast, antiviral mechanisms initiated by interferon (IFN) signaling predominate in mammals. Whilst mammalian IFN-induced miRNA are known to inhibit specific viruses, it is not known whether host-directed microRNAs, downstream of IFN-signaling, have a role in mediating broad antiviral resistance. By performing an integrative, systematic, global analysis of RNA turnover utilizing 4-thiouridine labeling of newly transcribed RNA and pri/pre-miRNA in IFN-activated macrophages, we identify a new post-transcriptional viral defense mechanism mediated by miR-342-5p. On the basis of ChIP and site-directed promoter mutagenesis experiments, we find the synthesis of miR-342-5p is coupled to the antiviral IFN response via the IFN-induced transcription factor, IRF1. Strikingly, we find miR-342-5p targets mevalonate-sterol biosynthesis using a multihit mechanism suppressing the pathway at different functional levels: transcriptionally via SREBF2, post-transcriptionally via miR-33, and enzymatically via IDI1 and SC4MOL. Mass spectrometry-based lipidomics and enzymatic assays demonstrate the targeting mechanisms reduce intermediate sterol pathway metabolites and total cholesterol in macrophages. These results reveal a previously unrecognized mechanism by which IFN regulates the sterol pathway. The sterol pathway is known to be an integral part of the macrophage IFN antiviral response, and we show that miR-342-5p exerts broad antiviral effects against multiple, unrelated pathogenic viruses such Cytomegalovirus and Influenza A (H1N1). Metabolic rescue experiments confirm the specificity of these effects and demonstrate that unrelated viruses have differential mevalonate and sterol pathway requirements for their replication. This study, therefore, advances the general concept of broad antiviral defense through multihit targeting of a single host pathway.

Community nurse-led initiation of antiviral therapy for chronic hepatitis C in people who inject drugs does not increase uptake of or adherence to treatment.

PubMed

Lewis, Heather; Kunkel, Jan; Axten, David; Dalton, Jane; Gardner, Hayley; Tippett, Andrew; Wynne, Stephanie; Wilkinson, Mandie; Foster, Graham R

2016-11-01

Chronic hepatitis C is common in people who inject drugs (PWID) and this population serves as a reservoir for infection. Treatment levels are low among this group, ranging from 1 to 19%. We explored whether a nurse-initiated community treatment model increased uptake of and adherence to interferon-based therapies. This was a cluster randomized trial of nurse-initiated versus physician-initiated antiviral therapy with pegylated interferon and ribavirin for hepatitis C virus in community clinics (trial registration: ISRCTN07774040). The proportion of participants initiating treatment during follow-up was 10% with nurse-initiated (6/62) and 9% with physician-initiated (6/76) therapy. Adherence was similar in both groups, with only one patient in each arm not adhering to therapy. There were no serious adverse events, but interferon-related side effects were common. Drug and alcohol use did not change during therapy. Despite easy access to antiviral therapy, uptake of treatment was poor, with no significant difference between the groups. Nurse-led initiation of interferon-based antiviral therapy in PWID did not lead to increased uptake of, response to or adherence with treatment. Further service improvement is unlikely to increase the proportion of PWID undergoing antiviral therapy for hepatitis C virus and early adoption of interferon-free regimens may increase the proportion initiating and completing treatment.

Gene Therapy Approaches to Human Immunodeficiency Virus and Other Infectious Diseases.

PubMed

Rogers, Geoffrey L; Cannon, Paula M

2017-10-01

Advances in gene therapy technologies, particularly in gene editing, are suggesting new avenues for the treatment of human immunodeficiency virus and other infectious diseases. This article outlines recent developments in antiviral gene therapies, including those based on the disruption of entry receptors or that target viral genomes using targeted nucleases, such as the CRISPR/Cas9 system. In addition, new ways to express circulating antiviral factors, such as antibodies, and approaches to harness and engineer the immune system to provide an antiviral effect that is not naturally achieved are described. Copyright © 2017 Elsevier Inc. All rights reserved.

Solute Carrier NTCP Regulates Innate Antiviral Immune Responses Targeting Hepatitis C Virus Infection of Hepatocytes.

PubMed

Verrier, Eloi R; Colpitts, Che C; Bach, Charlotte; Heydmann, Laura; Zona, Laetitia; Xiao, Fei; Thumann, Christine; Crouchet, Emilie; Gaudin, Raphaël; Sureau, Camille; Cosset, François-Loïc; McKeating, Jane A; Pessaux, Patrick; Hoshida, Yujin; Schuster, Catherine; Zeisel, Mirjam B; Baumert, Thomas F

2016-10-25

Chronic hepatitis B, C, and D virus (HBV, HCV, and HDV) infections are the leading causes of liver disease and cancer worldwide. Recently, the solute carrier and sodium taurocholate co-transporter NTCP has been identified as a receptor for HBV and HDV. Here, we uncover NTCP as a host factor regulating HCV infection. Using gain- and loss-of-function studies, we show that NTCP mediates HCV infection of hepatocytes and is relevant for cell-to-cell transmission. NTCP regulates HCV infection by augmenting the bile-acid-mediated repression of interferon-stimulated genes (ISGs), including IFITM3. In conclusion, our results uncover NTCP as a mediator of innate antiviral immune responses in the liver, and they establish a role for NTCP in the infection process of multiple viruses via distinct mechanisms. Collectively, our findings suggest a role for solute carriers in the regulation of innate antiviral responses, and they have potential implications for virus-host interactions and antiviral therapies. Copyright © 2016 The Author(s). Published by Elsevier Inc. All rights reserved.

Targeted antiviral prophylaxis with oseltamivir in a summer camp setting.

PubMed

Kimberlin, David W; Escude, Janell; Gantner, Janel; Ott, Jeanne; Dronet, Melissa; Stewart, Timothy A; Jester, Penelope; Redden, David T; Chapman, Whitney; Hammond, Rob

2010-04-01

To describe the effectiveness of containment of novel influenza A(H1N1) infection at a summer camp. Targeted use of oseltamivir phosphate by individuals in close contact with influenza-confirmed cases. Boys' camp in Alabama in July 2009. A total of 171 campers, 48 camp counselors, and 27 camp staff. Campers with confirmed influenza received oseltamivir and were immediately isolated and sent home. All boys and counselors in the infected child's adjoining cabins received prophylactic oseltamivir for 10 days, including 8 campers at higher risk for influenza infection (eg, those with asthma, seizure disorder, or diabetes). Alcohol-based hand sanitizer was provided at each of the daily activities, in the boys' cabins, and in the dining hall, and counselors were educated by the medical staff on the spread of influenza and its prevention through good hand hygiene. All cabins, bathrooms, and community sports equipment were sprayed or wiped down with disinfectant each day. Main Outcome Measure Virologic confirmation of influenza. Three of the 171 campers tested positive for influenza A during the course of the 2-week fourth session, for an attack rate of 1.8%. The probability of observing 3 or fewer infected campers if the attack rate was 12% is less than 1 in 10,000,000 (P < .0000001). An exact 95% confidence interval based on 3 events among 171 individuals estimates the attack rate to be between 0.3% and 5.0%. While 31% to 57% of campers, counselors, or staff experienced nausea with the treatment, this did not result in discontinuation of therapy. No campers tested positive for influenza A after returning home at the end of the camp session. In conjunction with comprehensive hand sanitization and surface decontamination, a targeted approach to antiviral prophylaxis contained the spread of influenza in a summer camp setting.

Antiviral therapy for hepatitis C: Has anything changed for pregnant/lactating women?

PubMed Central

Spera, Anna Maria; Eldin, Tarek Kamal; Tosone, Grazia; Orlando, Raffaele

2016-01-01

Hepatitis C virus (HCV) affects about 3% of the world’s population, with the highest prevalence in individuals under 40. The prevalence in pregnant women varies with geographical distribution (highest in developing countries). Prevalence also increases in sub-populations of women at high risk for blood-transmitted infections. HCV infection in pregnancy represents a non-negligible problem. However, most of the past antiviral regimens cannot be routinely offered to pregnant or breastfeeding women because of their side effects. We briefly reviewed the issue of treatment of HCV infection in pregnant/breastfeeding women focusing on the effects of the new direct-acting antivirals on fertility, pregnancy and lactation in animal studies and on the potential risk for humans based on the pharmacokinetic properties of each drug. Currently, all new therapy regimens are contraindicated in this setting because of lack of sufficient safety information and adequate measures of contraception are still routinely recommended for female patients of childbearing potential. PMID:27134703

Antiviral therapy for hepatitis C: Has anything changed for pregnant/lactating women?

PubMed

Spera, Anna Maria; Eldin, Tarek Kamal; Tosone, Grazia; Orlando, Raffaele

2016-04-28

Hepatitis C virus (HCV) affects about 3% of the world's population, with the highest prevalence in individuals under 40. The prevalence in pregnant women varies with geographical distribution (highest in developing countries). Prevalence also increases in sub-populations of women at high risk for blood-transmitted infections. HCV infection in pregnancy represents a non-negligible problem. However, most of the past antiviral regimens cannot be routinely offered to pregnant or breastfeeding women because of their side effects. We briefly reviewed the issue of treatment of HCV infection in pregnant/breastfeeding women focusing on the effects of the new direct-acting antivirals on fertility, pregnancy and lactation in animal studies and on the potential risk for humans based on the pharmacokinetic properties of each drug. Currently, all new therapy regimens are contraindicated in this setting because of lack of sufficient safety information and adequate measures of contraception are still routinely recommended for female patients of childbearing potential.

Flavocoxid exerts a potent antiviral effect against hepatitis B virus.

PubMed

Pollicino, Teresa; Musolino, Cristina; Irrera, Natasha; Bitto, Alessandra; Lombardo, Daniele; Timmoneri, Martina; Minutoli, Letteria; Raimondo, Giovanni; Squadrito, Giovanni; Squadrito, Francesco; Altavilla, Domenica

2018-01-01

Flavocoxid is a proprietary blend of two flavonoids, baicalin and catechin, and recent evidence has shown that bioflavonoids may exert antiviral activities. The potential antiviral activity of Flavocoxid against hepatitis B virus (HBV) was evaluated. Additionally, it was investigated if Flavocoxid used in combination with Entecavir could potentiate its anti-HBV activity. Hepatoma cells replicating HBV were treated with Flavocoxid, or Entecavir alone or in combination for up to 5 days. Viral replicative intermediates, transcripts, and cccDNA levels were evaluated in HBV-replicating cells by real-time PCR, Southern and Northern blotting. Expression profiling was performed using TaqMan low-density arrays. Flavocoxid treatment induced a reduction of HBV replicative intermediates, the amount of transcripts, and HBsAg levels. Flavocoxid and Entecavir combination therapy further decreased the amount of HBV replicative intermediates, compared to Flavocoxid alone. Importantly, Flavocoxid alone or in combination with Entecavir also induced a reduction of cccDNA. Gene-expression analysis showed that Flavocoxid activates type I IFNs-signaling and dampens the HBV-induced inflammatory response. Flavocoxid inhibits HBV replication by targeting multiple steps of viral life cycle. These results indicate that the antiviral activity of Entecavir is potentiated by Flavocoxid, suggesting that this medical food might be considered as an adjuvant for anti-HBV therapy.

[Comparative analysis of the effectiveness of antiviral therapy of children with infectious mononucleosis].

PubMed

Baranova, I P; Kurmaeva, D Iu

2013-01-01

A group of 126 children (4 to 7 years old) with infectious mononucleosis received basic therapy in combination with nonspecific antiviral drugs. The same therapeutic efficiency was observed for cycloferon and genferon light included in complex treatment of infectious mononucleosis in children. The use of cycloferon (10 mg/kg i.m., single daily injection for 10 days) prevents the development of frequent acute respiratory viral infections in the period of convalescence.

Transdermal delivery and cutaneous targeting of antivirals using a penetration enhancer and lysolipid prodrugs.

PubMed

Diblíková, Denisa; Kopečná, Monika; Školová, Barbora; Krečmerová, Marcela; Roh, Jaroslav; Hrabálek, Alexandr; Vávrová, Kateřina

2014-04-01

In this work, we investigate prodrug and enhancer approaches for transdermal and topical delivery of antiviral drugs belonging to the 2,6-diaminopurine acyclic nucleoside phosphonate (ANP) group. Our question was whether we can differentiate between transdermal and topical delivery, i.e., to control the delivery of a given drug towards either systemic absorption or retention in the skin. The in vitro transdermal delivery and skin concentrations of seven antivirals, including (R)- and (S)-9-[2-(phosphonomethoxy)propyl]-2,6-diaminopurine (PMPDAP), (S)-9-[3-hydroxy-2-(phosphonomethoxy)propyl]-2,6-diaminopurine ((S)-HPMPDAP), its 8-aza analog, and their cyclic and hexadecyloxypropyl (HDP) prodrugs, was investigated with and without the penetration enhancer dodecyl-6-(dimethylamino)hexanoate (DDAK) using human skin. The ability of ANPs to cross the human skin barrier was very low (0.5-1.4 nmol/cm(2)/h), and the majority of the compounds were found in the stratum corneum, the uppermost skin layer. The combination of antivirals and the penetration enhancer DDAK proved to be a viable approach for transdermal delivery, especially in case of (R)-PMPDAP, an anti-HIV effective drug (30.2 ± 2.3 nmol/cm(2)/h). On the other hand, lysophospholipid-like HDP prodrugs, e.g., HDP-(S)-HPMPDAP, reached high concentrations in viable epidermis without significant systemic absorption. By using penetration enhancers or lysolipid prodrugs, it is possible to effectively target systemic diseases by the transdermal route or to target cutaneous pathologies by topical delivery.

Antiviral prophylaxis during chemotherapy or immunosuppressive drug therapy to prevent HBV reactivation in patients with resolved HBV infection: a systematic review and meta-analysis.

PubMed

Su, Yi-Chia; Lin, Pei-Chin; Yu, Hsien-Chung; Wu, Chih-Chien

2018-05-29

Until recently, the role of antiviral prophylaxis in preventing hepatitis B virus (HBV) reactivation during immunosuppressive therapy or chemotherapy in patients with resolved HBV infection was unclear. The aim of the study reported here was to compare the efficacy of antiviral prophylaxis versus that of non-prophylaxis in resolved HBV-infected patients undergoing chemotherapy or immunosuppressive therapy. PubMed, the Cochrane library, and the ClinicalTrials.gov website were searched from inception until December 2017. Studies comparing reactivation in prophylaxis versus non-prophylaxis in patients undergoing immunosuppressive therapy or chemotherapy were included. The meta-analysis was performed to calculate the relative risk (RR) and the pooled estimates. A meta-analysis was conducted of 13 studies (2 randomized controlled trials [RCTs] and 11 cohort studies). The summary RR for HBV reactivation was 0.47 (95% confidence interval [CI] 0.13-1.69) for antiviral prophylaxis versus non-prophylaxis. Both of the RCTs included in the meta-analysis enrolled patients treated with rituximab. Subgroup analyses showed that the two RCTs ± high-quality cohort studies showed a decreased risk of HBV reactivation among the antiviral prophylaxis groups (RCT 1: RR 0.13, 95% CI 0.02-0.70; P = 0.02; RCT 2: 0.28, 95% CI 0.08-0.98; P = 0.05). Subgroup analyses further showed that the cohort studies did not support an association between the antiviral prophylaxis groups and HBV reactivation (RR 0.62, 95% CI 0.14-2.83; P = 0.54); adjusting for confounding factors, such as detectable anti-HBs antibodies, failed to produce a significant association (RR,0.29, 95% CI 0.07-1.28; P = 0.10). Our meta-analyses did not show an association between antiviral prophylaxis use and risk of HBV reactivation. As using only the RCTs ± high-quality cohort studies data rendered this association significant, clinicians can consider providing antiviral prophylaxis to patients with resolved

Parkin negatively regulates the antiviral signaling pathway by targeting TRAF3 for degradation.

PubMed

Xin, Di; Gu, Haiyan; Liu, Enping; Sun, Qinmiao

2018-06-14

Chronic neuroinflammation is a characteristic of Parkinson's disease (PD). Previous investigations have shown that Parkin gene mutations are related to the early-onset recessive form of PD and isolated juvenile-onset PD. Further, Parkin plays important roles in mitochondrial quality control and cytokine-induced cell death. However, whether Parkin regulates other cellular events is still largely unknown. In this study, we performed overexpression and knockout experiments, and found that Parkin negatively regulates antiviral immune responses against RNA and DNA viruses. Mechanistically, we show that Parkin interacts with tumor necrosis factor receptor-associated factor 3 (TRAF3) to regulate stability of TRAF3 protein by promoting K48-linked ubiquitination. Our findings suggest that Parkin plays a novel role in innate immune signaling by targeting TRAF3 for degradation, and maintaining the balance of innate antiviral immunity. Published under license by The American Society for Biochemistry and Molecular Biology, Inc.

Closing the door on flaviviruses: entry as a target for antiviral drug design.

PubMed

Perera, Rushika; Khaliq, Mansoora; Kuhn, Richard J

2008-10-01

With the emergence and rapid spread of West Nile virus in the United States since 1999, and the 50-100 million infections per year caused by dengue virus globally, the threat of flaviviruses as re-emerging human pathogens has become a reality. To support the efforts that are currently being pursued to develop effective vaccines against these viruses, researchers are also actively pursuing the development of small molecule compounds that target various aspects of the virus life cycle. Recent advances in the structural characterization of the flaviviruses have provided a strong foundation towards these efforts. These studies have provided the pseudo-atomic structures of virions from several members of the genus as well as atomic resolution structures of several viral proteins. Most importantly, these studies have highlighted specific structural rearrangements that occur within the virion that are necessary for the virus to complete its life cycle. These rearrangements occur when the virus must transition from immature, to mature, to fusion-active states and rely heavily on the conformational flexibility of the envelope (E) protein that forms the outer glycoprotein shell of the virus. Analysis of these conformational changes can suggest promising targets for structure-based antiviral design. For instance, by targeting the flexibility of the E protein, it might be possible to inhibit required rearrangements of this protein and trap the virus in a specific state. This would interfere with a productive flaviviral infection. This review presents a structural perspective of the flavivirus life cycle and focuses on the role of the E protein as an opportune target for structure-based antiviral drug design.

Experimental therapies for yellow fever

PubMed Central

Julander, Justin G.

2013-01-01

A number of viruses in the family Flaviviridae are the focus of efforts to develop effective antiviral therapies. Success has been achieved with inhibitors for the treatment of hepatitis C, and there is interest in clinical trials of drugs against dengue fever. Antiviral therapies have also been evaluated in patients with Japanese encephalitis and West Nile encephalitis. However, no treatment has been developed against the prototype flavivirus, yellow fever virus (YFV). Despite the availability of the live, attenuated 17D vaccine, thousands of cases of YF continue to occur each year in Africa and South America, with a significant mortality rate. In addition, a small number of vaccinees develop severe systemic infections with the 17D virus. This paper reviews current efforts to develop antiviral therapies, either directly targeting the virus or blocking detrimental host responses to infection. PMID:23237991

Direct-acting antivirals and host-targeting strategies to combat enterovirus infections.

PubMed

Bauer, Lisa; Lyoo, Heyrhyoung; van der Schaar, Hilde M; Strating, Jeroen Rpm; van Kuppeveld, Frank Jm

2017-06-01

Enteroviruses (e.g., poliovirus, enterovirus-A71, coxsackievirus, enterovirus-D68, rhinovirus) include many human pathogens causative of various mild and more severe diseases, especially in young children. Unfortunately, antiviral drugs to treat enterovirus infections have not been approved yet. Over the past decades, several direct-acting inhibitors have been developed, including capsid binders, which block virus entry, and inhibitors of viral enzymes required for genome replication. Capsid binders and protease inhibitors have been clinically evaluated, but failed due to limited efficacy or toxicity issues. As an alternative approach, host-targeting inhibitors with potential broad-spectrum activity have been identified. Furthermore, drug repurposing screens have recently uncovered promising new inhibitors with disparate viral and host targets. Together, these findings raise hope for the development of (broad-range) anti-enteroviral drugs. Copyright © 2017 Elsevier B.V. All rights reserved.

HIV-derived vectors for gene therapy targeting dendritic cells.

PubMed

Rossetti, Maura; Cavarelli, Mariangela; Gregori, Silvia; Scarlatti, Gabriella

2013-01-01

Human immunodeficiency virus type 1 (HIV-1)-derived lentiviral vectors (LV) have the potential to mediate stable therapeutic gene transfer. However, similarly to other viral vectors, their benefit is compromised by the induction of an immune response toward transgene-expressing cells that closely mimics antiviral immunity. LV share with the parental HIV the ability to activate dendritic cells (DC), while lack the peculiar ability of subverting DC functions, which is responsible for HIV immune escape. Understanding the interaction between LV and DC, with plasmacytoid and myeloid DC playing fundamental and distinct roles, has paved the way to novel approaches aimed at regulating transgene-specific immune responses. Thanks to the ability to target either DC subsets LV might be a powerful tool to induce immunity (i.e., gene therapy of cancer), cell death (i.e., in HIV/AIDS infection), or tolerance (i.e., gene therapy strategies for monogenic diseases). In this chapter, similarities and differences between the LV-mediated and HIV-mediated induction of immune responses, with specific focus on their interactions with DC, are discussed.

Longitudinal Liver Stiffness Assessment in Patients with Chronic Hepatitis C Undergoing Antiviral Therapy

PubMed Central

Martinez, Stella M.; Foucher, Juliette; Combis, Jean-Marc; Métivier, Sophie; Brunetto, Maurizia; Capron, Dominique; Bourlière, Marc; Bronowicki, Jean-Pierre; Dao, Thong; Maynard-Muet, Marianne; Lucidarme, Damien; Merrouche, Wassil; Forns, Xavier; de Lédinghen, Victor

2012-01-01

Background/Aims Liver stiffness (LS) measurement by means of transient elastography (TE) is accurate to predict fibrosis stage. The effect of antiviral treatment and virologic response on LS was assessed and compared with untreated patients with chronic hepatitis C (CHC). Methods TE was performed at baseline, and at weeks 24, 48, and 72 in 515 patients with CHC. Results 323 treated (62.7%) and 192 untreated patients (37.3%) were assessed. LS experienced a significant decline in treated patients and remained stable in untreated patients at the end of study (P<0.0001). The decline was significant for patients with baseline LS ≥ 7.1 kPa (P<0.0001 and P 0.03, for LS ≥9.5 and ≥7.1 kPa vs lower values, respectively). Sustained virological responders and relapsers had a significant LS improvement whereas a trend was observed in nonresponders (mean percent change −16%, −10% and −2%, for SVR, RR and NR, respectively, P 0.03 for SVR vs NR). In multivariate analysis, high baseline LS (P<0.0001) and ALT levels, antiviral therapy and non-1 genotype were independent predictors of LS improvement. Conclusions LS decreases during and after antiviral treatment in patients with CHC. The decrease is significant in sustained responders and relapsers (particularly in those with high baseline LS) and suggests an improvement in liver damage. PMID:23082200

Antiviral Natural Products and Herbal Medicines

PubMed Central

Lin, Liang-Tzung; Hsu, Wen-Chan; Lin, Chun-Ching

2014-01-01

Viral infections play an important role in human diseases, and recent outbreaks in the advent of globalization and ease of travel have underscored their prevention as a critical issue in safeguarding public health. Despite the progress made in immunization and drug development, many viruses lack preventive vaccines and efficient antiviral therapies, which are often beset by the generation of viral escape mutants. Thus, identifying novel antiviral drugs is of critical importance and natural products are an excellent source for such discoveries. In this mini-review, we summarize the antiviral effects reported for several natural products and herbal medicines. PMID:24872930

Cellular Antiviral Factors that Target Particle Infectivity of HIV-1.

PubMed

Goffinet, Christine

2016-01-01

In the past decade, the identification and characterization of antiviral genes with the ability to interfere with virus replication has established cell-intrinsic innate immunity as a third line of antiviral defense in addition to adaptive and classical innate immunity. Understanding how cellular factors have evolved to inhibit HIV-1 reveals particularly vulnerable points of the viral replication cycle. Many, but not all, antiviral proteins share type I interferon-upregulated expression and sensitivity to viral counteraction or evasion measures. Whereas well-established restriction factors interfere with early post-entry steps and release of HIV-1, recent research has revealed a diverse set of proteins that reduce the infectious quality of released particles using individual, to date poorly understood modes of action. These include induction of paucity of mature glycoproteins in nascent virions or self-incorporation into the virus particle, resulting in poor infectiousness of the virion and impaired spread of the infection. A better understanding of these newly discovered antiviral factors may open new avenues towards the design of drugs that repress the spread of viruses whose genomes have already integrated.

Elbasvir/Grazoprevir, an Alternative in Antiviral Hepatitis C Therapy in Patients under Amiodarone Treatment

PubMed Central

Weiss, Lina; Wustmann, Kerstin; Semmo, Mariam; Schwerzmann, Markus; Semmo, Nasser

2018-01-01

A sofosbuvir/ledipasvir combination is part of a first-line treatment of hepatitis C. However, in patients concurrently treated with amiodarone, cardiac side effects have been described, resulting in an official warning in 2015 by the American Food and Drug Administration and the European Medicines Agency when combining those substances. This deprived numerous hepatitis C patients with concurrent cardiovascular problems of receiving this highly effective treatment. Here we present a treatment alternative with an elbasvir/grazoprevir regimen, based on our successful treatment of a patient under concurrent amiodarone therapy. Our observations indicate that patients treated with amiodarone can finally benefit from effective antiviral therapy. PMID:29606942

Development of novel entry inhibitors targeting emerging viruses

PubMed Central

Zhou, Yanchen; Simmons, Graham

2013-01-01

Emerging viral diseases pose a unique risk to public health, and thus there is a need to develop therapies. A current focus of funding agencies, and hence research, is the development of broad-spectrum antivirals, and in particular, those targeting common cellular pathways. The scope of this article is to review screening strategies and recent advances in this area, with a particular emphasis on antivirals targeting the step of viral entry for emerging lipid-enveloped viruses such as Ebola virus and SARS-coronavirus. PMID:23199399

3,7-Dideazaneplanocin: Synthesis and antiviral analysis.

PubMed

Yin, Xue-Qiang; Schneller, Stewart W

2017-12-01

Objective To synthesize 3,7-dideazaneplanocin and evaluate its antiviral potential. Methods The target 3,7-dideazaneplanocin has been prepared in five steps from a readily available cyclopentenol. A thorough in vitro antiviral analysis was conducted versus both DNA and RNA viruses. Results A rational synthesis of 3,7-dideazaneplanocin was conceived and successfully pursued in such a way that it can be adapted to various analogs of 3,7-dideazaneplanocin. Using standard antiviral assays, no activity for 3,7-dideazaneplanocn was found. Conclusion Two structural features are necessary for adenine-based carbocyclic nucleosides (like neplanocin) for potential antiviral properties: (i) inhibition of S-adenosylhomocysteine hydrolase and/or (ii) C-5' activation via the mono-nucleotide. These two requisite adenine structural features to fit these criteria are not present in in the target 3,7-dideazaneplanocin: (i) an N-7 is necessary for inhibition of the hydrolase and the N-3 is claimed to be essential for phosphorylation at C-5'. Thus, it is not surprising that 3,7-dideazaneplaoncin lacked antiviral properties.

Antiviral treatment for Bell's palsy (idiopathic facial paralysis).

PubMed

Lockhart, Pauline; Daly, Fergus; Pitkethly, Marie; Comerford, Natalia; Sullivan, Frank

2009-10-07

Antiviral agents against herpes simplex virus are widely used in the treatment of idiopathic facial paralysis (Bell's palsy), but their effectiveness is uncertain. Significant morbidity can be associated with severe cases. This review addresses the effect of antiviral therapy on Bell's palsy. We updated the search of the Cochrane Neuromuscular Disease Group Trials Register (December 2008), MEDLINE (from January 1966 to December 8 2008), EMBASE (from January 1980 to December 8 2008) and LILACS (from January 1982 to December 2008). Randomized trials of antivirals with and without corticosteroids versus control therapies for the treatment of Bell's palsy. Twenty-three papers were selected for consideration. Seven trials including 1987 participants met the inclusion criteria, adding five studies to the two in the previous review.Incomplete recovery at one year. There was no significant benefit in the rate of incomplete recovery from antivirals compared with placebo (n = 1886, RR 0.88, 95% CI 0.65 to 1.18). In meta-analyses with some unexplained heterogeneity, the outcome with antivirals was significantly worse than with corticosteroids (n = 768, RR 2.82, 95% CI 1.09 to 7.32) and the outcome with antivirals plus corticosteroids was significantly better than with placebo (n = 658, RR 0.56, 95% CI 0.41 to 0.76).Motor synkinesis or crocodile tears at one year. In single trials, there was no significant difference in long term sequelae comparing antivirals and corticosteroids with corticosteroids alone (n = 99, RR 0.39, 95% CI 0.14 to 1.07) or antivirals with corticosteroids (n = 101, RR 1.03, 95% CI 0.51 to 2.07).Adverse events.There was no significant difference in rates of adverse events between antivirals and placebo (n = 1544, RR 1.06, 95% CI 0.81 to 1.38), between antivirals and corticosteroids (n = 667, RR 0.96, 95% CI 0.65 to 1.41) or between the antiviral-corticosteroid combination and placebo (n = 658, RR 1.15, 95% CI 0.79 to 1.66). High quality evidence showed no

CMV Infection in Bone Marrow and Solid Organ Transplant Patients in the Era of Antiviral Prophylaxis.

PubMed

Hebart, Holger; Jahn, Gerhard; Sinzger, Christian; Kanz, Lothar; Einsele, Hermann

2000-02-01

Recent developments in the diagnosis and therapy of cytomegalovirus (CMV) infection have helped to reduce CMV-associated morbidity and mortality following allogeneic bone marrow and solid organ transplantation. The clinical symptoms of active CMV infection and the prevalence of life-threatening CMV disease vary widely between different patient populations according to the type of transplant and the intensity of immunosuppression employed. Antiviral prophylaxis with aciclovir, valaciclovir and ganciclovir has been shown to reduce CMV infection and disease following organ transplantation. Antiviral drugs, in particular ganciclovir and foscarnet, have varying sideeffects, however, and antiviral resistance due to prolonged administration of ganciclovir and foscarnet has been reported recently. Short courses of pre-emptive antiviral therapy for documented CMV infection help to reduce the duration and sideeffects of therapy, offering an alternative strategy to antiviral prophylaxis. Studies are required to compare the efficacy and costs of antiviral prophylaxis with pre-emptive therapy.

Targeted Therapy for Cancer

Cancer.gov

Targeted therapy is a type of cancer treatment that targets the changes in cancer cells that help them grow, divide, and spread. Learn how targeted therapy works against cancer and about side effects that may occur.

Modeling Viral Infectious Diseases and Development of Antiviral Therapies Using Human Induced Pluripotent Stem Cell-Derived Systems.

PubMed

Trevisan, Marta; Sinigaglia, Alessandro; Desole, Giovanna; Berto, Alessandro; Pacenti, Monia; Palù, Giorgio; Barzon, Luisa

2015-07-13

The recent biotechnology breakthrough of cell reprogramming and generation of induced pluripotent stem cells (iPSCs), which has revolutionized the approaches to study the mechanisms of human diseases and to test new drugs, can be exploited to generate patient-specific models for the investigation of host-pathogen interactions and to develop new antimicrobial and antiviral therapies. Applications of iPSC technology to the study of viral infections in humans have included in vitro modeling of viral infections of neural, liver, and cardiac cells; modeling of human genetic susceptibility to severe viral infectious diseases, such as encephalitis and severe influenza; genetic engineering and genome editing of patient-specific iPSC-derived cells to confer antiviral resistance.

Interferon-free therapy of chronic hepatitis C with direct-acting antivirals does not change the short-term risk for de novo hepatocellular carcinoma in patients with liver cirrhosis.

PubMed

Mettke, F; Schlevogt, B; Deterding, K; Wranke, A; Smith, A; Port, K; Manns, M P; Vogel, A; Cornberg, M; Wedemeyer, H

2018-02-01

Hepatitis C virus (HCV) clearance with IFN-based therapies reduces the incidence of hepatocellular carcinoma (HCC). There has been some debate if IFN-free therapy with direct-acting antivirals alters the risk for HCC. To investigate the HCC incidence in cirrhotic HCV patients who cleared HCV with direct-acting antivirals vs untreated controls. We prospectively monitored 373 patients with chronic hepatitis C who received IFN-free therapies with direct-acting antiviral after January 2014. A retrospective control cohort of untreated cirrhotic patients was recruited out of 3715 HCV patients who were followed at our centre between 2007 and 2013, with similar HCC screening protocols. 158 direct-acting antiviral-treated and 184 control patients with liver cirrhosis were included in this analysis. The groups did not differ in gender and genotype distribution, severity of liver disease and prevalence of diabetes mellitus. Patients were followed up for a median of 440 (range 91-908) and 592 (range 90-1000) days. HCCs developed in 6 and 14 patients during follow-up, resulting in an incidence of 2.90 vs 4.48 HCCs per 100 person-years. In the direct-acting antiviral-treated group, there was no new case of HCC later than 450 days after treatment initiation. In multivariate analysis, higher MELD-Scores and AFP-levels were independently associated with HCC development. Transplant-free patient survival was similar in both groups. IFN-free direct-acting antiviral therapy of chronic hepatitis C does not alter the short-term risk for HCC in patients with liver cirrhosis. A reduced HCC incidence may become evident after more than 1.5 years of follow-up. © 2017 John Wiley & Sons Ltd.

Hepatitis C Virus and Antiviral Drug Resistance.

PubMed

Kim, Seungtaek; Han, Kwang-Hyub; Ahn, Sang Hoon

2016-11-15

Since its discovery in 1989, hepatitis C virus (HCV) has been intensively investigated to understand its biology and develop effective antiviral therapies. The efforts of the previous 25 years have resulted in a better understanding of the virus, and this was facilitated by the development of in vitro cell culture systems for HCV replication. Antiviral treatments and sustained virological responses have also improved from the early interferon monotherapy to the current all-oral regimens using direct-acting antivirals. However, antiviral resistance has become a critical issue in the treatment of chronic hepatitis C, similar to other chronic viral infections, and retreatment options following treatment failure have become important questions. Despite the clinical challenges in the management of chronic hepatitis C, substantial progress has been made in understanding HCV, which may facilitate the investigation of other closely related flaviviruses and lead to the development of antiviral agents against these human pathogens.

TRIM25 Enhances the Antiviral Action of Zinc-Finger Antiviral Protein (ZAP)

PubMed Central

Lau, Zerlina; Cheung, Pamela; Schneider, William M.; Bozzacco, Leonia; Buehler, Eugen; Takaoka, Akinori; Rice, Charles M.; Felsenfeld, Dan P.; MacDonald, Margaret R.

2017-01-01

The host factor and interferon (IFN)-stimulated gene (ISG) product, zinc-finger antiviral protein (ZAP), inhibits a number of diverse viruses by usurping and intersecting with multiple cellular pathways. To elucidate its antiviral mechanism, we perform a loss-of-function genome-wide RNAi screen to identify cellular cofactors required for ZAP antiviral activity against the prototype alphavirus, Sindbis virus (SINV). In order to exclude off-target effects, we carry out stringent confirmatory assays to verify the top hits. Important ZAP-liaising partners identified include proteins involved in membrane ion permeability, type I IFN signaling, and post-translational protein modification. The factor contributing most to the antiviral function of ZAP is TRIM25, an E3 ubiquitin and ISG15 ligase. We demonstrate here that TRIM25 interacts with ZAP through the SPRY domain, and TRIM25 mutants lacking the RING or coiled coil domain fail to stimulate ZAP’s antiviral activity, suggesting that both TRIM25 ligase activity and its ability to form oligomers are critical for its cofactor function. TRIM25 increases the modification of both the short and long ZAP isoforms by K48- and K63-linked polyubiquitin, although ubiquitination of ZAP does not directly affect its antiviral activity. However, TRIM25 is critical for ZAP’s ability to inhibit translation of the incoming SINV genome. Taken together, these data uncover TRIM25 as a bona fide ZAP cofactor that leads to increased ZAP modification enhancing its translational inhibition activity. PMID:28060952

TRIM25 Enhances the Antiviral Action of Zinc-Finger Antiviral Protein (ZAP).

PubMed

Li, Melody M H; Lau, Zerlina; Cheung, Pamela; Aguilar, Eduardo G; Schneider, William M; Bozzacco, Leonia; Molina, Henrik; Buehler, Eugen; Takaoka, Akinori; Rice, Charles M; Felsenfeld, Dan P; MacDonald, Margaret R

2017-01-01

The host factor and interferon (IFN)-stimulated gene (ISG) product, zinc-finger antiviral protein (ZAP), inhibits a number of diverse viruses by usurping and intersecting with multiple cellular pathways. To elucidate its antiviral mechanism, we perform a loss-of-function genome-wide RNAi screen to identify cellular cofactors required for ZAP antiviral activity against the prototype alphavirus, Sindbis virus (SINV). In order to exclude off-target effects, we carry out stringent confirmatory assays to verify the top hits. Important ZAP-liaising partners identified include proteins involved in membrane ion permeability, type I IFN signaling, and post-translational protein modification. The factor contributing most to the antiviral function of ZAP is TRIM25, an E3 ubiquitin and ISG15 ligase. We demonstrate here that TRIM25 interacts with ZAP through the SPRY domain, and TRIM25 mutants lacking the RING or coiled coil domain fail to stimulate ZAP's antiviral activity, suggesting that both TRIM25 ligase activity and its ability to form oligomers are critical for its cofactor function. TRIM25 increases the modification of both the short and long ZAP isoforms by K48- and K63-linked polyubiquitin, although ubiquitination of ZAP does not directly affect its antiviral activity. However, TRIM25 is critical for ZAP's ability to inhibit translation of the incoming SINV genome. Taken together, these data uncover TRIM25 as a bona fide ZAP cofactor that leads to increased ZAP modification enhancing its translational inhibition activity.

Identification of broad-spectrum antiviral compounds and assessment of the druggability of their target for efficacy against respiratory syncytial virus (RSV)

PubMed Central

Bonavia, Aurelio; Franti, Michael; Pusateri Keaney, Erin; Kuhen, Kelli; Seepersaud, Mohindra; Radetich, Branko; Shao, Jian; Honda, Ayako; Dewhurst, Janetta; Balabanis, Kara; Monroe, James; Wolff, Karen; Osborne, Colin; Lanieri, Leanne; Hoffmaster, Keith; Amin, Jakal; Markovits, Judit; Broome, Michelle; Skuba, Elizabeth; Cornella-Taracido, Ivan; Joberty, Gerard; Bouwmeester, Tewis; Hamann, Lawrence; Tallarico, John A.; Tommasi, Ruben; Compton, Teresa; Bushell, Simon M.

2011-01-01

The search for novel therapeutic interventions for viral disease is a challenging pursuit, hallmarked by the paucity of antiviral agents currently prescribed. Targeting of viral proteins has the inextricable challenge of rise of resistance. Safe and effective vaccines are not possible for many viral pathogens. New approaches are required to address the unmet medical need in this area. We undertook a cell-based high-throughput screen to identify leads for development of drugs to treat respiratory syncytial virus (RSV), a serious pediatric pathogen. We identified compounds that are potent (nanomolar) inhibitors of RSV in vitro in HEp-2 cells and in primary human bronchial epithelial cells and were shown to act postentry. Interestingly, two scaffolds exhibited broad-spectrum activity among multiple RNA viruses. Using the chemical matter as a probe, we identified the targets and identified a common cellular pathway: the de novo pyrimidine biosynthesis pathway. Both targets were validated in vitro and showed no significant cell cytotoxicity except for activity against proliferative B- and T-type lymphoid cells. Corollary to this finding was to understand the consequences of inhibition of the target to the host. An in vivo assessment for antiviral efficacy failed to demonstrate reduced viral load, but revealed microscopic changes and a trend toward reduced pyrimidine pools and findings in histopathology. We present here a discovery program that includes screen, target identification, validation, and druggability that can be broadly applied to identify and interrogate other host factors for antiviral effect starting from chemical matter of unknown target/mechanism of action. PMID:21502533

Identification of broad-spectrum antiviral compounds and assessment of the druggability of their target for efficacy against respiratory syncytial virus (RSV).

PubMed

Bonavia, Aurelio; Franti, Michael; Pusateri Keaney, Erin; Kuhen, Kelli; Seepersaud, Mohindra; Radetich, Branko; Shao, Jian; Honda, Ayako; Dewhurst, Janetta; Balabanis, Kara; Monroe, James; Wolff, Karen; Osborne, Colin; Lanieri, Leanne; Hoffmaster, Keith; Amin, Jakal; Markovits, Judit; Broome, Michelle; Skuba, Elizabeth; Cornella-Taracido, Ivan; Joberty, Gerard; Bouwmeester, Tewis; Hamann, Lawrence; Tallarico, John A; Tommasi, Ruben; Compton, Teresa; Bushell, Simon M

2011-04-26

The search for novel therapeutic interventions for viral disease is a challenging pursuit, hallmarked by the paucity of antiviral agents currently prescribed. Targeting of viral proteins has the inextricable challenge of rise of resistance. Safe and effective vaccines are not possible for many viral pathogens. New approaches are required to address the unmet medical need in this area. We undertook a cell-based high-throughput screen to identify leads for development of drugs to treat respiratory syncytial virus (RSV), a serious pediatric pathogen. We identified compounds that are potent (nanomolar) inhibitors of RSV in vitro in HEp-2 cells and in primary human bronchial epithelial cells and were shown to act postentry. Interestingly, two scaffolds exhibited broad-spectrum activity among multiple RNA viruses. Using the chemical matter as a probe, we identified the targets and identified a common cellular pathway: the de novo pyrimidine biosynthesis pathway. Both targets were validated in vitro and showed no significant cell cytotoxicity except for activity against proliferative B- and T-type lymphoid cells. Corollary to this finding was to understand the consequences of inhibition of the target to the host. An in vivo assessment for antiviral efficacy failed to demonstrate reduced viral load, but revealed microscopic changes and a trend toward reduced pyrimidine pools and findings in histopathology. We present here a discovery program that includes screen, target identification, validation, and druggability that can be broadly applied to identify and interrogate other host factors for antiviral effect starting from chemical matter of unknown target/mechanism of action.

Direct-Acting Antiviral Therapy Outcomes in Canadian Chronic Hepatitis C Telemedicine Patients.

PubMed

Cooper, Curtis L; Hatashita, Holly; Corsi, Daniel J; Parmar, Parmvir; Corrin, Raymond; Garber, Gary

Many of the 300,000 HCV-infected Canadians live in under-served and remote areas without access to HCV healthcare specialists. Telemedicine (TM) and advances in HCV management can facilitate linkage of these marginalized patients to healthcare. A cohort database analysis was performed on patients followed at The Ottawa Hospital and Regional Viral Hepatitis Program between January 2012 and August 2016. We compared patient characteristics, fibrosis work-up and antiviral treatment outcomes in TM (n = 157) and non-TM (n = 1,130) patients (The Ottawa Hospital Viral Hepatitis Outpatient Clinic) residing in Eastern Ontario. TM patients were more often infected with genotype 3 (25.9% vs. 16.4%), were more commonly Indigenous (7.0% vs. 2.2%) had a history of injection drug use (70.1% vs. 54.9%) and incarceration (46.5% vs 35.5%). Groups were comparable in age (48.9 years), gender (63.7% male) and cirrhotic stage (24.0%). 59.2% of TM patients underwent transient elastography during regional outreach blitzes compared to 61.8% of non-TM patients (p = 0.54). Overall, half as many TM patients initiated antiviral therapy as non-TM patients (27.4% vs. 53.8%, p < 0.001). The introduction of DAA regimens is bridging this gap (22.2% of TM patients vs. 34.3% of non-TM patients). SVR rates with interferon-free, DAA regimens were 94.7% and 94.8% in TM and non-TM groups (p = 0.99). Our TM program engages and retains a population that faces many barriers to effective HCV treatment. TM patients initiated HCV therapy and achieved High SVR rates comparable to those obtained using traditional models of care.

Boosting immunity by antiviral drug therapy: A simple relationship among timing, efficacy, and success

NASA Astrophysics Data System (ADS)

Komarova, Natalia L.; Barnes, Eleanor; Klenerman, Paul; Wodarz, Dominik

2003-02-01

Drug therapies against persistent human infections such as hepatitis C virus, hepatitis B virus, and HIV fail to consistently eradicate the infection from the host. Hence, recent emphasis has shifted to the study of antiviral therapy aimed at boosting specific immune responses. It was argued that structured therapy interruptions were required to achieve this, because such regimes have shown promising results in early HIV infection. Using mathematical models, we show that, contrary to this notion, a single phase of drug therapy can result in the establishment of sustained immunity. We present a simple relationship between timing of therapy and efficacy of the drugs required for success. In the presence of strong viral suppression, we show that therapy should be stopped relatively early, and that a longer duration of treatment leads to failure. On the other hand, in the presence of weaker viral suppression, stopping treatment too early is detrimental, and therapy has to be continued beyond a time threshold. We discuss our modeling results primarily in the context of HCV therapy during chronic infection. Although the therapy regimes explored here also have implications for HIV, virus-mediated destruction of specific immune cells renders success unlikely during the chronic phase of the infection.

Cellular immune responses in patients with hepatitis B surface antigen seroclearance induced by antiviral therapy

PubMed Central

2011-01-01

Background The mechanisms by which chronic hepatitis B is completely resolved through antiviral therapy are unknown, and the contribution of acquired T cell immunity to hepatitis B surface antigen (HBsAg) seroclearance has not been investigated. Therefore, we measured the T-cell responses to core and envelope antigens in patients with HBsAg seroclearance. Methods Fourteen subjects with HBsAg seroclearance following antiviral treatment for chronic hepatitis B, 7 HBeAg-positive immunotolerant HBV carriers and 9 HBeAg-negative inactive HBsAg carriers were recruited. HBV-specific T-cell responses to recombinant HBV core (rHBcAg) and envelope (rHBsAg) proteins and pools of core and envelope peptides were measured using an ELISPOT assay detecting interferon-gamma and intracellular cytokine staining (ICS) assays detecting interferon-gamma or interleukin 2. Results Interferon-gamma ELISPOT assays showed a low frequency of weak responses to the rHBsAg and S peptide pool in the HBsAg seroclearance group, and the response frequency to the rHBcAg and the C peptide pool was higher than to the rHBsAg (P < 0.001) and S peptide pool (P = 0.001) respectively. A higher response frequency to C than S peptide pools was confirmed in the interferon-gamma ICS assays for both CD4+ (P = 0.033) and CD8+ (P = 0.040) T cells in the HBsAg seroclearance group. The responses to C and S antigens in the inactive carriers were similar. Conclusions There was a low frequency of CD4+ and CD8+ T cell immune responses to envelope antigens in Chinese subjects with HBsAg seroclearance following antiviral therapy. It is unlikely that these immune responses are responsible for HBsAg seroclearance in these subjects. PMID:21320337

Light-activated nanotube-porphyrin conjugates as effective antiviral agents

NASA Astrophysics Data System (ADS)

Banerjee, Indrani; Douaisi, Marc P.; Mondal, Dhananjoy; Kane, Ravi S.

2012-03-01

Porphyrins have been used for photodynamic therapy (PDT) against a wide range of targets like bacteria, viruses and tumor cells. In this work, we report porphyrin-conjugated multi-walled carbon nanotubes (NT-P) as potent antiviral agents. Specifically, we used Protoporphyrin IX (PPIX), which we attached to acid-functionalized multi-walled carbon nanotubes (MWNTs). We decided to use carbon nanotubes as scaffolds because of their ease of recovery from a solution through filtration. In the presence of visible light, NT-P was found to significantly reduce the ability of Influenza A virus to infect mammalian cells. NT-P may be used effectively against influenza viruses with little or no chance of them developing resistance to the treatment. Furthermore, NT-P can be easily recovered through filtration which offers a facile strategy to reuse the active porphyrin moiety to its fullest extent. Thus NT-P conjugates represent a new approach for preparing ex vivo reusable antiviral agents.

A multi-scale mathematical modeling framework to investigate anti-viral therapeutic opportunities in targeting HIV-1 accessory proteins

PubMed Central

Suryawanshi, Gajendra W.; Hoffmann, Alexander

2015-01-01

Human immunodeficiency virus-1 (HIV-1) employs accessory proteins to evade innate immune responses by neutralizing the anti-viral activity of host restriction factors. Apolipoprotein B mRNA-editing enzyme 3G (APOBEC3G, A3G) and bone marrow stromal cell antigen 2 (BST2) are host resistance factors that potentially inhibit HIV-1 infection. BST2 reduces viral production by tethering budding HIV-1 particles to virus producing cells, while A3G inhibits the reverse transcription (RT) process and induces viral genome hypermutation through cytidine deamination, generating fewer replication competent progeny virus. Two HIV-1 proteins counter these cellular restriction factors: Vpu, which reduces surface BST2, and Vif, which degrades cellular A3G. The contest between these host and viral proteins influences whether HIV-1 infection is established and progresses towards AIDS. In this work, we present an age-structured multi-scale viral dynamics model of in vivo HIV-1 infection. We integrated the intracellular dynamics of anti-viral activity of the host factors and their neutralization by HIV-1 accessory proteins into the virus/cell population dynamics model. We calculate the basic reproductive ratio (Ro) as a function of host-viral protein interaction coefficients, and numerically simulated the multi-scale model to understand HIV-1 dynamics following host factor-induced perturbations. We found that reducing the influence of Vpu triggers a drop in Ro, revealing the impact of BST2 on viral infection control. Reducing Vif’s effect reveals the restrictive efficacy of A3G in blocking RT and in inducing lethal hypermutations, however, neither of these factors alone is sufficient to fully restrict HIV-1 infection. Interestingly, our model further predicts that BST2 and A3G function synergistically, and delineates their relative contribution in limiting HIV-1 infection and disease progression. We provide a robust modeling framework for devising novel combination therapies that

Antiviral Activity of HIV gp120 Targeting Bispecific T Cell Engager (BiTE®) Antibody Constructs.

PubMed

Brozy, Johannes; Schlaepfer, Erika; Mueller, Christina K S; Rochat, Mary-Aude; Rampini, Silvana K; Myburgh, Renier; Raum, Tobias; Kufer, Peter; Baeuerle, Patrick A; Muenz, Markus; Speck, Roberto F

2018-05-02

Today's gold standard in HIV therapy is the combined antiretroviral therapy (cART). It requires strict adherence by patients and life-long medication, which can lower the viral load below detection limits and prevent HIV-associated immunodeficiency, but cannot cure patients. The bispecific T cell engaging (BiTE®) antibody technology has demonstrated long-term relapse-free outcomes in patients with relapsed and refractory acute lymphocytic leukemia. We here generated BiTE® antibody constructs that target the HIV-1 envelope protein gp120 (HIV gp120) using either the scFv B12 or VRC01, the first two extracellular domains (1+2) of human CD4 alone or joined to the single chain variable fragment (scFv) of the antibody 17b fused to an anti-human CD3ϵ scFv. These engineered human BiTE® antibody constructs showed engagement of T cells for redirected lysis of HIV gp120-transfected CHO cells. Furthermore, they substantially inhibited HIV-1 replication in PBMCs as well as in macrophages co-cultured with autologous CD8+ T-cells, the most potent being the human CD4(1+2) BiTE® antibody construct and the CD4(1+2)L17b BiTE® antibody construct. The CD4(1+2) h BiTE® antibody construct promoted HIV infection of human CD4-/CD8+ T cells. In contrast, the neutralizing B12 and the VRC01 BiTE® antibody constructs as well as the CD4(1+2)L17b BiTE® antibody construct did not. Thus, BiTE® antibody constructs targeting HIV gp120 are very promising for constraining HIV and warrant further development as novel antiviral therapy with curative potential. Importance HIV is a chronic infection well controlled with the current cART. However, we lack cure of HIV, and the HIV pandemic goes on. Here we showed in vitro and ex vivo t hat a bispecific T-cell engaging (BiTE®) antibody construct targeting HIV gp120 resulted in substantially reduced HIV replication. In addition, these BiTE® antibody constructs display efficient killing of gp120 expressing cells and inhibited replication in ex vivo

Viral eradication reduces both liver stiffness and steatosis in patients with chronic hepatitis C virus infection who received direct-acting anti-viral therapy.

PubMed

Tada, T; Kumada, T; Toyoda, H; Sone, Y; Takeshima, K; Ogawa, S; Goto, T; Wakahata, A; Nakashima, M; Nakamuta, M; Tanaka, J

2018-04-01

Whether direct-acting anti-viral therapy can reduce liver fibrosis and steatosis in patients with chronic hepatitis C virus (HCV) infection is unclear. To evaluate changes in liver stiffness and steatosis in patients with HCV who received direct-acting anti-viral therapy and achieved sustained virological response (SVR). A total of 198 patients infected with HCV genotype 1 or 2 who achieved SVR after direct-acting anti-viral therapy were analysed. Liver stiffness as evaluated by magnetic resonance elastography, steatosis as evaluated by magnetic resonance imaging-determined proton density fat fraction (PDFF), insulin resistance, and laboratory data were assessed before treatment (baseline) and at 24 weeks after the end of treatment (SVR24). Alanine aminotransferase and homeostatic model assessment-insulin resistance levels decreased significantly from baseline to SVR24. Conversely, platelet count, which is inversely associated with liver fibrosis, increased significantly from baseline to SVR24. In patients with high triglyceride levels (≥150 mg/dL), triglyceride levels significantly decreased from baseline to SVR24 (P = 0.004). The median (interquartile range) liver stiffness values at baseline and SVR24 were 3.10 (2.70-4.18) kPa and 2.80 (2.40-3.77) kPa respectively (P < 0.001). The PDFF values at baseline and SVR 24 were 2.4 (1.7-3.4)% and 1.9 (1.3-2.8)% respectively (P < 0.001). In addition, 68% (19/28) of patients with fatty liver at baseline (PDFF ≥5.2%; n = 28) no longer had fatty liver (PDFF <5.2%) at SVR24. Viral eradication reduces both liver stiffness and steatosis in patients with chronic HCV who received direct-acting anti-viral therapy (UMIN000017020). © 2018 John Wiley & Sons Ltd.

The flavivirus NS2B-NS3 protease-helicase as a target for antiviral drug development.

PubMed

Luo, Dahai; Vasudevan, Subhash G; Lescar, Julien

2015-06-01

The flavivirus NS3 protein is associated with the endoplasmic reticulum membrane via its close interaction with the central hydrophilic region of the NS2B integral membrane protein. The multiple roles played by the NS2B-NS3 protein in the virus life cycle makes it an attractive target for antiviral drug discovery. The N-terminal region of NS3 and its cofactor NS2B constitute the protease that cleaves the viral polyprotein. The NS3 C-terminal domain possesses RNA helicase, nucleoside and RNA triphosphatase activities and is involved both in viral RNA replication and virus particle formation. In addition, NS2B-NS3 serves as a hub for the assembly of the flavivirus replication complex and also modulates viral pathogenesis and the host immune response. Here, we review biochemical and structural advances on the NS2B-NS3 protein, including the network of interactions it forms with NS5 and NS4B and highlight recent drug development efforts targeting this protein. This article forms part of a symposium in Antiviral Research on flavivirus drug discovery. Copyright © 2015 Elsevier B.V. All rights reserved.

Reduction in liver transplant wait-listing in the era of direct-acting antiviral therapy.

PubMed

Flemming, Jennifer A; Kim, W Ray; Brosgart, Carol L; Terrault, Norah A

2017-03-01

Direct-acting antiviral (DAA) therapy, recently approved for patients with decompensated cirrhosis (DC) secondary to hepatitis C virus (HCV), is associated with improved hepatic function. We analyzed trends in liver transplant (LT) wait-listing (WL) to explore potential impact of effective medical therapy on WL registration. This is a cohort study using the Scientific Registry of Transplant Recipients database from 2003 to 2015. A total of 47,591 adults wait-listed for LT from HCV, hepatitis B virus (HBV), and nonalcoholic steatohepatitis (NASH) were identified. LT indication was defined as DC if the Model for End-Stage Liver Disease (MELD) at WL was ≥15 or hepatocellular carcinoma (HCC). Era of listing was divided into interferon (IFN; 2003-2010), protease inhibitor (PI; 2011-2013), and direct-acting antiviral (DAA; 2014-2015). Annual standardized incidence rates of WL were analyzed using Poisson regression. Adjusted incidences of LT WL for DC in HCV patients decreased by 5% in the PI era (P = 0.004) and 32% in the DAA era (P < 0.001) compared to the IFN era. Listing for DC in HBV also decreased in the PI (-17%; P = 0.002) and DAA eras (-24%; P < 0.001). Conversely, WL for DC in NASH increased by 41% in the PI era (P < 0.001) and 81% in the DAA era (P < 0.001). WL for HCC in both the HCV and NASH populations increased in both the PI and DAA eras (P < 0.001 for all) whereas HCC WL in HBV remained stable (P > 0.05 for all). The rate of LT WL for HCV complicated by DC has decreased by over 30% in the era of DAA therapy. Further reductions in WL are anticipated with increased testing, linkage to care, and access to DAA therapy. (Hepatology 2017;65:804-812). © 2016 by the American Association for the Study of Liver Diseases.

Antiviral treatment for Bell's palsy (idiopathic facial paralysis).

PubMed

Gagyor, Ildiko; Madhok, Vishnu B; Daly, Fergus; Somasundara, Dhruvashree; Sullivan, Michael; Gammie, Fiona; Sullivan, Frank

2015-11-09

Corticosteroids are widely used in the treatment of idiopathic facial paralysis (Bell's palsy), but the effectiveness of additional treatment with an antiviral agent is uncertain. Significant morbidity can be associated with severe cases of Bell's palsy. This review was first published in 2001 and revised several times, most recently in 2009. This version replaces an update of the review in Issue 7 of the Cochrane Library subsequently withdrawn because of an ongoing investigation into the reliability of data from an included study. To assess the effects of antiviral treatments alone or in combination with any other therapy for Bell's palsy. On 7 October 2014 we searched the Cochrane Neuromuscular Disease Group Specialized Register, CENTRAL, MEDLINE, EMBASE, LILACS, DARE, NHS EED, and HTA. We also reviewed the bibliographies of the identified trials and contacted trial authors and known experts in the field and relevant drug companies to identify additional published or unpublished data. We searched clinical trials registries for ongoing studies. We considered randomised controlled trials or quasi-randomised controlled trials of antivirals with and without corticosteroids versus control therapies for the treatment of Bell's palsy. We excluded trials that had a high risk of bias in several domains. Pairs of authors independently assessed trials for relevance, eligibility, and risk of bias, using standard Cochrane procedures. Ten trials, including 2280 participants, met the inclusion criteria and are included in the final analysis. Some of the trials were small, and a number were at high or unclear risk of bias. Other trials did not meet current best standards in allocation concealment and blinding. Incomplete recoveryWe found a significant benefit from adding antivirals to corticosteroids in comparison with corticosteroids alone for people with Bell's palsy (risk ratio (RR) 0.61, 95% confidence interval (CI) 0.39 to 0.97, n = 1315). For people with severe Bell

Antiviral treatment for Bell's palsy (idiopathic facial paralysis).

PubMed

Gagyor, Ildiko; Madhok, Vishnu B; Daly, Fergus; Somasundara, Dhruvashree; Sullivan, Michael; Gammie, Fiona; Sullivan, Frank

2015-07-01

Corticosteroids are widely used in the treatment of idiopathic facial paralysis (Bell's palsy), but the effectiveness of additional treatment with an antiviral agent is uncertain. Significant morbidity can be associated with severe cases of Bell's palsy. To assess the effects of antiviral treatments alone or in combination with any other therapy for Bell's palsy. On 7 October 2014 we searched the Cochrane Neuromuscular Disease Group Specialized Register, CENTRAL, MEDLINE, EMBASE, LILACS, DARE, NHS EED, and HTA. We also reviewed the bibliographies of the identified trials and contacted trial authors and known experts in the field and relevant drug companies to identify additional published or unpublished data. We searched clinical trials registries for ongoing studies. We considered randomised controlled trials or quasi-randomised controlled trials of antivirals with and without corticosteroids versus control therapies for the treatment of Bell's palsy. We excluded trials that had a high risk of bias in several domains. Pairs of authors independently assessed trials for relevance, eligibility, and risk of bias, using standard Cochrane procedures. Eleven trials, including 2883 participants, met the inclusion criteria and are included in the final analysis. We added four studies to the previous review for this update. Some of the trials were small, and a number were at high or unclear risk of bias. Other trials did not meet current best standards in allocation concealment and blinding. Incomplete recoveryWe found no significant benefit from adding antivirals to corticosteroids in comparison with corticosteroids alone for people with Bell's palsy (risk ratio (RR) 0.69, 95% confidence interval (CI) 0.47 to 1.02, n = 1715). For people with severe Bell's palsy (House-Brackmann scores of 5 and 6 or the equivalent in other scales), we found a reduction in the rate of incomplete recovery at month six when antivirals plus corticosteroids were used (RR 0.64, 95% CI 0.41 to 0

A Novel Antiviral Target Structure Involved in the RNA Binding, Dimerization, and Nuclear Export Functions of the Influenza A Virus Nucleoprotein

PubMed Central

Yamada, Kazunori; Kondoh, Yasumitsu; Hikono, Hirokazu; Osada, Hiroyuki; Tomii, Kentaro; Saito, Takehiko; Aida, Yoko

2015-01-01

Developing antiviral therapies for influenza A virus (IAV) infection is an ongoing process because of the rapid rate of antigenic mutation and the emergence of drug-resistant viruses. The ideal strategy is to develop drugs that target well-conserved, functionally restricted, and unique surface structures without affecting host cell function. We recently identified the antiviral compound, RK424, by screening a library of 50,000 compounds using cell-based infection assays. RK424 showed potent antiviral activity against many different subtypes of IAV in vitro and partially protected mice from a lethal dose of A/WSN/1933 (H1N1) virus in vivo. Here, we show that RK424 inhibits viral ribonucleoprotein complex (vRNP) activity, causing the viral nucleoprotein (NP) to accumulate in the cell nucleus. In silico docking analysis revealed that RK424 bound to a small pocket in the viral NP. This pocket was surrounded by three functionally important domains: the RNA binding groove, the NP dimer interface, and nuclear export signal (NES) 3, indicating that it may be involved in the RNA binding, oligomerization, and nuclear export functions of NP. The accuracy of this binding model was confirmed in a NP-RK424 binding assay incorporating photo-cross-linked RK424 affinity beads and in a plaque assay evaluating the structure-activity relationship of RK424. Surface plasmon resonance (SPR) and pull-down assays showed that RK424 inhibited both the NP-RNA and NP-NP interactions, whereas size exclusion chromatography showed that RK424 disrupted viral RNA-induced NP oligomerization. In addition, in vitro nuclear export assays confirmed that RK424 inhibited nuclear export of NP. The amino acid residues comprising the NP pocket play a crucial role in viral replication and are highly conserved in more than 7,000 NP sequences from avian, human, and swine influenza viruses. Furthermore, we found that the NP pocket has a surface structure different from that of the pocket in host molecules. Taken

Targeted enzyme prodrug therapies.

PubMed

Schellmann, N; Deckert, P M; Bachran, D; Fuchs, H; Bachran, C

2010-09-01

The cure of cancer is still a formidable challenge in medical science. Long-known modalities including surgery, chemotherapy and radiotherapy are successful in a number of cases; however, invasive, metastasized and inaccessible tumors still pose an unresolved and ongoing problem. Targeted therapies designed to locate, detect and specifically kill tumor cells have been developed in the past three decades as an alternative to treat troublesome cancers. Most of these therapies are either based on antibody-dependent cellular cytotoxicity, targeted delivery of cytotoxic drugs or tumor site-specific activation of prodrugs. The latter is a two-step procedure. In the first step, a selected enzyme is accumulated in the tumor by guiding the enzyme or its gene to the neoplastic cells. In the second step, a harmless prodrug is applied and specifically converted by this enzyme into a cytotoxic drug only at the tumor site. A number of targeting systems, enzymes and prodrugs were investigated and improved since the concept was first envisioned in 1974. This review presents a concise overview on the history and latest developments in targeted therapies for cancer treatment. We cover the relevant technologies such as antibody-directed enzyme prodrug therapy (ADEPT), gene-directed enzyme prodrug therapy (GDEPT) as well as related therapies such as clostridial- (CDEPT) and polymer-directed enzyme prodrug therapy (PDEPT) with emphasis on prodrug-converting enzymes, prodrugs and drugs.

Antiviral drug resistance and helicase-primase inhibitors of herpes simplex virus.

PubMed

Field, Hugh J; Biswas, Subhajit

2011-02-01

A new class of chemical inhibitors has been discovered that interferes with the process of herpesvirus DNA replication. To date, the majority of useful herpesvirus antivirals are nucleoside analogues that block herpesvirus DNA replication by targeting the DNA polymerase. The new helicase-primase inhibitors (HPI) target a different enzyme complex that is also essential for herpesvirus DNA replication. This review will place the HPI in the context of previous work on the nucleoside analogues. Several promising highly potent HPI will be described with a particular focus on the identification of drug-resistance mutations. Several HPI have good pharmacological profiles and are now at the outset of phase II clinical trials. Provided there are no safety issues to stop their progress, this new class of compound will be a major advance in the herpesvirus antiviral field. Furthermore, HPI are likely to have a major impact on the therapy and prevention of herpes simplex virus and varicella zoster in both immunocompetent and immunocompromised patients alone or in combination with current nucleoside analogues. The possibility of acquired drug-resistance to HPI will then become an issue of great practical importance. Copyright © 2010 Elsevier Ltd. All rights reserved.

Small interfering RNA against the 2C genomic region of coxsackievirus B3 exerts potential antiviral effects in permissive HeLa cells.

PubMed

Luan, Ying; Dai, Hai-Li; Yang, Dan; Zhu, Lin; Gao, Tie-Lei; Shao, Hong-Jiang; Peng, Xue; Jin, Zhan-Feng

2012-01-01

Coxsackievirus B3 (CVB3) is the most important causal agent of viral heart muscle disease, but no specific antiviral drug is currently available. Small interfering RNA (siRNA) has been used as an antiviral therapeutic strategy via posttranscriptional gene silencing. In this study, eleven siRNAs were designed to target seven distinct regions of the CVB3 genome including VP1, VP2, VP3, 2A, 2C, 3C, and 3D. All of the siRNAs were individually transfected into HeLa cells, which were subsequently infected with CVB3. The impacts of RNA interference (RNAi) on viral replication were evaluated using five measures: cytopathic effect (CPE), 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, 50% tissue culture infectious dose (TCID(50)), real-time RT-PCR, and Western blot. Five of the eleven siRNAs were highly efficient at inhibiting viral replication. This was especially true for siRNA-5, which targeted the ATPase 2C. However, antiviral activity varied significantly among siRNA-9, -10, and -11 even though that they all targeted the 3D region. Our results revealed several effective targets for CVB3 silencing, and provided evidence that sequences except CRE within the 2C region may also be potential targets for CVB3-specific siRNAs design. These data supported a potential role of RNA interference in future antiviral intervention therapies. Copyright © 2011 Elsevier B.V. All rights reserved.

Magnitude and Kinetics of Decrease in Liver Stiffness After Antiviral Therapy in Patients With Chronic Hepatitis C: A Systematic Review and Meta-analysis.

PubMed

Singh, Siddharth; Facciorusso, Antonio; Loomba, Rohit; Falck-Ytter, Yngve T

2018-01-01

We performed a systematic review and meta-analysis to estimate the decrease in liver stiffness, measured by vibration-controlled transient elastrography (VCTE), in patients with hepatitis C virus infection who achieved a sustained virologic response (SVR). We searched the literature through October 2016 for observational studies or randomized controlled trials of adults with hepatitis C virus infection who received antiviral therapy (either direct-acting antiviral agents or interferon-based therapies), underwent liver stiffness measurement using VCTE before starting therapy, and had at least 1 follow-up VCTE after completion of therapy; studies also provided data on mean or median liver stiffness measurements for patients who did and did not achieve an SVR. We identified 24 studies, and estimated weighted mean difference (and 95% confidence interval) in liver stiffness in patients with versus without SVR using random-effects meta-analysis. In patients who achieved SVR, liver stiffness decreased by 2.4 kPa at the end of therapy (95% CI, -1.7 to -3.0), by 3.1 kPa 1-6 months after therapy (95% CI, -1.6 to -4.7), by 3.2 kPa 6-12 months after therapy (90% CI, -2.6 to -3.9), and 4.1 kPa 12 months or more after therapy (95% CI, -3.3 to -4.9) (median decrease, 28.2%; interquartile range, 21.8-34.8). In contrast, there was no significant change in liver stiffness in patients who did not achieve an SVR (at 6-12 months after therapy, decrease of 0.6 kPa; 95% CI, -1.7 to 0.5). Decreases in liver stiffness were significantly greater in patients treated with direct-acting antiviral agents than with interferon-based therapy (decrease of 4.5 kPa vs decrease of 2.6 kPa; P = .03), cirrhosis at baseline (decrease of 5.1 kPa vs decrease of 2.8 kPa in patients with no cirrhosis; P = .02), or high pretreatment levels of alanine aminotransferase (P < .01). Among patients with baseline liver stiffness >9.5 kPa, 47% (95% CI, 27%-68%) achieved posttreatment liver stiffness of <9

WITHDRAWN. Antiviral treatment for Bell's palsy (idiopathic facial paralysis).

PubMed

Gagyor, Ildiko; Madhok, Vishnu B; Daly, Fergus; Somasundara, Dhruvashree; Sullivan, Michael; Gammie, Fiona; Sullivan, Frank

2015-05-04

Corticosteroids are widely used in the treatment of idiopathic facial paralysis (Bell's palsy), but the effectiveness of additional treatment with an antiviral agent is uncertain. Significant morbidity can be associated with severe cases of Bell's palsy. To assess the effects of antiviral treatments alone or in combination with any other therapy for Bell's palsy. On 7 October 2014 we searched the Cochrane Neuromuscular Disease Group Specialized Register, CENTRAL, MEDLINE, EMBASE, LILACS, DARE, NHS EED, and HTA. We also reviewed the bibliographies of the identified trials and contacted trial authors and known experts in the field and relevant drug companies to identify additional published or unpublished data. We searched clinical trials registries for ongoing studies. We considered randomised controlled trials or quasi-randomised controlled trials of antivirals with and without corticosteroids versus control therapies for the treatment of Bell's palsy. We excluded trials that had a high risk of bias in several domains. Pairs of authors independently assessed trials for relevance, eligibility, and risk of bias, using standard Cochrane procedures. Eleven trials, including 2883 participants, met the inclusion criteria and are included in the final analysis. We added four studies to the previous review for this update. Some of the trials were small, and a number were at high or unclear risk of bias. Other trials did not meet current best standards in allocation concealment and blinding. Incomplete recoveryWe found no significant benefit from adding antivirals to corticosteroids in comparison with corticosteroids alone for people with Bell's palsy (risk ratio (RR) 0.69, 95% confidence interval (CI) 0.47 to 1.02, n = 1715). For people with severe Bell's palsy (House-Brackmann scores of 5 and 6 or the equivalent in other scales), we found a reduction in the rate of incomplete recovery at month six when antivirals plus corticosteroids were used (RR 0.64, 95% CI 0.41 to 0

[Studies on evaluation of natural products for antiviral effects and their applications].

PubMed

Hayashi, Toshimitsu

2008-01-01

In the search for novel antiviral molecules from natural products, we have discovered various antiviral molecules with characteristic mechanisms of action. Scopadulciol (SDC), isolated from the tropical medicinal plant Scoparia dulcis L., showed stimulatory effects on the antiviral potency of acyclovir (ACV) or ganciclovir (GCV). This effect of SDC was exerted via the activation of viral thymidine kinase (HSV-1 TK) and, as a result, an increase in the cellular concentration of the active form of ACV/GCV, i.e., the triphosphate of ACV or GCV. On the basis of these experimental results, cancer gene therapy using the HSV-1 tk gene and ACV/GCV together with SDC was found to be effective in suppressing the growth of cancer cells in animals. Acidic polysaccharides such as calcium spirulan (Ca-SP) from Spirulina platensis, nostoflan from Nostoc flagelliforme, and a fucoidan from the sporophyll of Undaria pinnatifida (mekabu fucoidan) were also found to be potent inhibitors against several enveloped viruses. Their antiviral potency was dependent on molecular weight and content of the sulfate or carboxyl group as well as counterion species chelating with sulfate groups, indicating the importance of the three-dimensional structure of the molecules. In addition, unlike dextran sulfate, Ca-SP was shown to target not only viral absorption/penetration stages but also some replication stages of progeny viruses after penetration into cells. When mekabu fucoidan or nostoflan was administered with oseltamivir phosphate, their synergistic antiviral effects on influenza A virus were confirmed in vitro as well as in vivo.

Antiviral therapy in hepatitis B virus-infected children with immune-tolerant characteristics: A pilot open-label randomized study.

PubMed

Zhu, Shishu; Zhang, Hongfei; Dong, Yi; Wang, Limin; Xu, Zhiqiang; Liu, Weiwei; Gan, Yu; Tang, Hongmei; Chen, Dawei; Wang, Fuchuan; Zhao, Pan

2018-06-01

Chronic infection with hepatitis B virus (HBV) in children is a serious health problem worldwide. How to treat children with immune-tolerant chronic hepatitis B infection, commonly characterized by hepatitis B e antigen (HBeAg) positivity, high viral load, normal or mildly elevated alanine aminotransferase and no or minimal inflammation in liver histology, remains unresolved. This trial aims to study the benefits of antiviral therapy in children with these characteristics. This is a pilot open-label randomized controlled study. From May 2014 to April 2015, 69 treatment-naive chronically HBV-infected children, aged 1 to 16 years, who had immune-tolerant characteristics were recruited to this trial and randomly assigned, in a 2:1 ratio, to treatment group and control group. Patients in the treatment group received either interferon-α (IFN) monotherapy or consecutively received IFN monotherapy, combination therapy of IFN and lamivudine (LAM), and LAM therapy alone. All patients were observed until week 96. At baseline, epidemiological, biochemical, serological, virological and histological indices were consistent across the treatment and control groups. Of the 46 patients in the treatment group, 73.91% had undetectable serum HBV DNA, 32.61% achieved HBeAg seroconversion and 21.74% lost hepatitis B surface antigen (HBsAg) at the endpoint. No LAM resistance emerged at week 96. In the control group, only one (4.35%) patient underwent spontaneous HBeAg seroconversion and had undetectable serum HBV DNA during observation, and moreover, none developed HBsAg clearance. For all patients, no serious adverse events were observed. Antiviral treatment with a sequential combination of IFN and LAM resulted in a significant improvement in the rates of undetectable serum HBV DNA, HBeAg seroconversion and HBsAg loss in children with chronic HBV infection and immune-tolerant characteristics. There is a lack of data regarding treatment of immune-tolerant chronic hepatitis B (CHB). It

Targeting HIV-1 gp41-induced fusion and pathogenesis for anti-viral therapy.

PubMed

Garg, Himanshu; Viard, Mathias; Jacobs, Amy; Blumenthal, Robert

2011-12-01

HIV gp41 is a metastable protein whose native conformation is maintained in the form of a heterodimer with gp120. The non-covalently associated gp41/gp120 complex forms a trimer on the virus surface. As gp120 engages with HIV's receptor, CD4, and coreceptor, CXCR4 or CCR5, gp41 undergoes several conformational changes resulting in fusion between the viral and cellular membranes. Several lipophilic and amphiphilic domains have been shown to be critical in that process. While the obvious function of gp41 in viral entry is well-established its role in cellular membrane fusion and the link with pathogenesis are only now beginning to appear. Recent targeting of gp41 via fusion inhibitors has revealed an important role of this protein not only in viral entry but also in bystander apoptosis and HIV pathogenesis. Studies by our group and others have shown that the phenomenon of gp41-mediated hemifusion initiates apoptosis in bystander cells and correlates with virus pathogenesis. More interestingly, recent clinical evidence suggests that gp41 mutants arising after Enfuvirtide therapy are associated with CD4 cell increase and immunological benefits. This has in turn been correlated to a decrease in bystander apoptosis in our in vitro as well as in vivo assays. Although a great deal of work has been done to unravel HIV-1 gp41-mediated fusion mechanisms, the factors that regulate gp41-mediated fusion versus hemifusion and the mechanism by which hemifusion initiates bystander apoptosis are not fully understood. Further insight into these issues will open new avenues for drug development making gp41 a critical anti-HIV target both for neutralization and virus attenuation.

A review on current status of antiviral siRNA.

PubMed

Qureshi, Abid; Tantray, Vaqar Gani; Kirmani, Altaf Rehman; Ahangar, Abdul Ghani

2018-04-15

Viral diseases like influenza, AIDS, hepatitis, and Ebola cause severe epidemics worldwide. Along with their resistant strains, new pathogenic viruses continue to be discovered so creating an ongoing need for new antiviral treatments. RNA interference is a cellular gene-silencing phenomenon in which sequence-specific degradation of target mRNA is achieved by means of complementary short interfering RNA (siRNA) molecules. Short interfering RNA technology affords a potential tractable strategy to combat viral pathogenesis because siRNAs are specific, easy to design, and can be directed against multiple strains of a virus by targeting their conserved gene regions. In this review, we briefly summarize the current status of siRNA therapy for representative examples from different virus families. In addition, other aspects like their design, delivery, medical significance, bioinformatics resources, and limitations are also discussed. Copyright © 2018 John Wiley & Sons, Ltd.

Bioengineering Strategies for Designing Targeted Cancer Therapies

PubMed Central

Wen, Xuejun

2014-01-01

The goals of bioengineering strategies for targeted cancer therapies are (1) to deliver a high dose of an anticancer drug directly to a cancer tumor, (2) to enhance drug uptake by malignant cells, and (3) to minimize drug uptake by nonmalignant cells. Effective cancer-targeting therapies will require both passive- and active targeting strategies and a thorough understanding of physiologic barriers to targeted drug delivery. Designing a targeted therapy includes the selection and optimization of a nanoparticle delivery vehicle for passive accumulation in tumors, a targeting moiety for active receptor-mediated uptake, and stimuli-responsive polymers for control of drug release. The future direction of cancer targeting is a combinatorial approach, in which targeting therapies are designed to use multiple targeting strategies. The combinatorial approach will enable combination therapy for delivery of multiple drugs and dual ligand targeting to improve targeting specificity. Targeted cancer treatments in development and the new combinatorial approaches show promise for improving targeted anticancer drug delivery and improving treatment outcomes. PMID:23768509

Nucleic acid polymers: Broad spectrum antiviral activity, antiviral mechanisms and optimization for the treatment of hepatitis B and hepatitis D infection.

PubMed

Vaillant, Andrew

2016-09-01

Antiviral polymers are a well-studied class of broad spectrum viral attachment/entry inhibitors whose activity increases with polymer length and with increased amphipathic (hydrophobic) character. The newest members of this class of compounds are nucleic acid polymers whose activity is derived from the sequence independent properties of phosphorothioated oligonucleotides as amphipathic polymers. Although the antiviral mechanisms and broad spectrum antiviral activity of nucleic acid polymers mirror the functionality of other members of this class, they exert in addition a unique post entry activity in hepatitis B infection which inhibits the release of HBsAg from infected hepatocytes. This review provides a general overview of the antiviral polymer class with a focus on nucleic acid polymers and their development as therapeutic agents for the treatment of hepatitis B/hepatitis D. This article forms part of a symposium in Antiviral Research on ''An unfinished story: from the discovery of the Australia antigen to the development of new curative therapies for hepatitis B.''. Copyright © 2016 The Author. Published by Elsevier B.V. All rights reserved.

Provider-patient in-office discussions of response to hepatitis C antiviral therapy and impact on patient comprehension.

PubMed

Hamilton, Heidi E; Nelson, Meaghan; Martin, Paul; Cotler, Scott J

2006-04-01

Providers need to communicate projected response rates effectively to enable patients with hepatitis C virus to make informed decisions about therapy. This study used interactional sociolinguistics (1) to evaluate how gastroenterologists and allied health professionals communicate information regarding response rates to antiviral therapy, (2) to determine how these discussions relate to where the patient is in the continuum of evaluation and treatment, (3) to assess whether patients were aligned with providers in their perceptions of response rates after office visits, and (4) to identify factors that improve provider-patient alignment. Gastroenterologists, allied health professionals, and patients with hepatitis C virus were videotaped and audiotaped during regularly scheduled visits. Postvisit interviews were conducted separately with patients and providers. Visits and postvisits were transcribed and analyzed using validated sociolinguistic techniques. The phase of hepatitis C virus treatment shaped the benchmarks of response talk, although across the treatment continuum providers overwhelmingly made strategic use of positive statistics, providing motivation. In postvisit interviews, 55% of providers and patients were aligned on response rates. Patients with a favorable outcome and patients who asked response-related questions in the visit were more likely to be aligned with providers. Areas identified for improvement included the tendency to discuss response rates before an individualized assessment could be made, balancing motivation and accuracy, and assessing the patient's perspective before delivering any bad news, if necessary. Sociolinguistic analysis provides a powerful tool to evaluate provider-patient interactions and to identify ways to improve in-office communication regarding antiviral therapy.

Prolonged detection of herpes simplex virus type 2 (HSV-2) DNA in cerebrospinal fluid despite antiviral therapy in a patient with HSV-2-associated radiculitis.

PubMed

Ganzenmueller, Tina; Karaguelle, Deniz; Schmitt, Corinna; Puppe, Wolfram; Stachan-Kunstyr, Rita; Bronzlik, Paul; Sauerbrei, Andreas; Wegner, Florian; Heim, Albert

2012-01-01

Herpes simplex virus type 2 (HSV-2) can cause radiculo-myelitis as a neurological manifestation. We report a case of ongoing HSV-2 DNA positivity in the cerebrospinal fluid (CSF) of at least eight weeks under antiviral therapy with acyclovir in a highly immunocompromised hemato-oncologic patient with HSV-2-associated radiculitis. Upon admission, the patient presented with pain, leg paresis, and urinary incontinence, as well as pleocytosis in the CSF. Quantitative real-time PCR of the CSF at day 3 after admission revealed HSV-2 with a concentration of 2.0×10(5) copies/ml and treatment with acyclovir intravenously and prednisolone by mouth was started. Clinical symptoms resolved almost completely after approximately 3 weeks of antiviral therapy. However, CSF samples of day 12, 19, 26, 33, 39, 48 and 54 after admission showed a slow decline of HSV-2 DNA concentrations. HSV-2 DNA was still detectable (1.6×10(4) copies/ml) at day 54 after admission. Genotypic resistance testing showed, as far as available, no mutations indicative for acyclovir resistance. Since an increasing specific antibody index for HSV was observed, we speculate that the prolonged detectability of HSV-2 DNA in the CSF might not necessarily indicate ongoing viral replication but neutralized virus. Other hypotheses and the consequences on treatment are discussed. To our knowledge this is the first report about the long-term viral load kinetics of HSV-2 in the CSF of a patient with radiculitis under antiviral therapy, highlighting the need for further studies on HSV DNA kinetics in the CSF and their significance for an appropriate antiviral treatment.

Reduced Mortality of Cytomegalovirus Pneumonia After Hematopoietic Cell Transplantation Due to Antiviral Therapy and Changes in Transplantation Practices

PubMed Central

Erard, Veronique; Guthrie, Katherine A.; Seo, Sachiko; Smith, Jeremy; Huang, MeeiLi; Chien, Jason; Flowers, Mary E. D.; Corey, Lawrence; Boeckh, Michael

2015-01-01

Background. Despite major advances in the prevention of cytomegalovirus (CMV) disease, the treatment of CMV pneumonia in recipients of hematopoietic cell transplant remains a significant challenge. Methods. We examined recipient, donor, transplant, viral, and treatment factors associated with overall and attributable mortality using Cox regression models. Results. Four hundred twenty-one cases were identified between 1986 and 2011. Overall survival at 6 months was 30% (95% confidence interval [CI], 25%–34%). Outcome improved after the year 2000 (all-cause mortality: adjusted hazard ratio [aHR], 0.7 [95% CI, .5–1.0]; P = .06; attributable mortality: aHR, 0.6 [95% CI, .4–.9]; P = .01). Factors independently associated with an increased risk of all-cause and attributable mortality included female sex, elevated bilirubin, lymphopenia, and mechanical ventilation; grade 3/4 acute graft-vs-host disease was associated with all-cause mortality only. An analysis of patients who received transplants in the current preemptive therapy era (n = 233) showed only lymphopenia and mechanical ventilation as significant risk factors for overall and attributable mortality. Antiviral treatment with ganciclovir or foscarnet was associated with improved outcome compared with no antiviral treatment. However, the addition of intravenous pooled or CMV-specific immunoglobulin to antiviral treatment did not seem to improve overall or attributable mortality. Conclusions. Outcome of CMV pneumonia showed a modest improvement over the past 25 years. However, advances seem to be due to antiviral treatment and changes in transplant practices rather than immunoglobulin-based treatments. Novel treatment strategies for CMV pneumonia are needed. PMID:25778751

Discovery of Influenza A Virus Sequence Pairs and Their Combinations for Simultaneous Heterosubtypic Targeting that Hedge against Antiviral Resistance

PubMed Central

Lin, Jing; Pramono, Zacharias Aloysius Dwi; Maurer-Stroh, Sebastian

2016-01-01

The multiple circulating human influenza A virus subtypes coupled with the perpetual genomic mutations and segment reassortment events challenge the development of effective therapeutics. The capacity to drug most RNAs motivates the investigation on viral RNA targets. 123,060 segment sequences from 35,938 strains of the most prevalent subtypes also infecting humans–H1N1, 2009 pandemic H1N1, H3N2, H5N1 and H7N9, were used to identify 1,183 conserved RNA target sequences (≥15-mer) in the internal segments. 100% theoretical coverage in simultaneous heterosubtypic targeting is achieved by pairing specific sequences from the same segment (“Duals”) or from two segments (“Doubles”); 1,662 Duals and 28,463 Doubles identified. By combining specific Duals and/or Doubles to form a target graph wherein an edge connecting two vertices (target sequences) represents a Dual or Double, it is possible to hedge against antiviral resistance besides maintaining 100% heterosubtypic coverage. To evaluate the hedging potential, we define the hedge-factor as the minimum number of resistant target sequences that will render the graph to become resistant i.e. eliminate all the edges therein; a target sequence or a graph is considered resistant when it cannot achieve 100% heterosubtypic coverage. In an n-vertices graph (n ≥ 3), the hedge-factor is maximal (= n– 1) when it is a complete graph i.e. every distinct pair in a graph is either a Dual or Double. Computational analyses uncover an extensive number of complete graphs of different sizes. Monte Carlo simulations show that the mutation counts and time elapsed for a target graph to become resistant increase with the hedge-factor. Incidentally, target sequences which were reported to reduce virus titre in experiments are included in our target graphs. The identity of target sequence pairs for heterosubtypic targeting and their combinations for hedging antiviral resistance are useful toolkits to construct target graphs for

Assembly-directed antivirals differentially bind quasiequivalent pockets to modify hepatitis B virus capsid tertiary and quaternary structure.

PubMed

Katen, Sarah P; Tan, Zhenning; Chirapu, Srinivas Reddy; Finn, M G; Zlotnick, Adam

2013-08-06

Hepatitis B virus (HBV) is a major cause of liver disease. Assembly of the HBV capsid is a critical step in virus production and an attractive target for new antiviral therapies. We determined the structure of HBV capsid in complex with AT-130, a member of the phenylpropenamide family of assembly effectors. AT-130 causes tertiary and quaternary structural changes but does not disrupt capsid structure. AT-130 binds a hydrophobic pocket that also accommodates the previously characterized heteroaryldihydropyrimidine compounds but favors a unique quasiequivalent location on the capsid surface. Thus, this pocket is a promiscuous drug-binding site and a likely target for different assembly effectors with a broad range of mechanisms of activity. That AT-130 successfully decreases virus production by increasing capsid assembly rate without disrupting capsid structure delineates a paradigm in antiviral design, that disrupting reaction timing is a viable strategy for assembly effectors of HBV and other viruses. Copyright © 2013 Elsevier Ltd. All rights reserved.

Flavivirus Infection Impairs Peroxisome Biogenesis and Early Antiviral Signaling

PubMed Central

You, Jaehwan; Hou, Shangmei; Malik-Soni, Natasha; Xu, Zaikun; Kumar, Anil; Rachubinski, Richard A.; Frappier, Lori

2015-01-01

ABSTRACT Flaviviruses are significant human pathogens that have an enormous impact on the global health burden. Currently, there are very few vaccines against or therapeutic treatments for flaviviruses, and our understanding of how these viruses cause disease is limited. Evidence suggests that the capsid proteins of flaviviruses play critical nonstructural roles during infection, and therefore, elucidating how these viral proteins affect cellular signaling pathways could lead to novel targets for antiviral therapy. We used affinity purification to identify host cell proteins that interact with the capsid proteins of West Nile and dengue viruses. One of the cellular proteins that formed a stable complex with flavivirus capsid proteins is the peroxisome biogenesis factor Pex19. Intriguingly, flavivirus infection resulted in a significant loss of peroxisomes, an effect that may be due in part to capsid expression. We posited that capsid protein-mediated sequestration and/or degradation of Pex19 results in loss of peroxisomes, a situation that could result in reduced early antiviral signaling. In support of this hypothesis, we observed that induction of the lambda interferon mRNA in response to a viral RNA mimic was reduced by more than 80%. Together, our findings indicate that inhibition of peroxisome biogenesis may be a novel mechanism by which flaviviruses evade the innate immune system during early stages of infection. IMPORTANCE RNA viruses infect hundreds of millions of people each year, causing significant morbidity and mortality. Chief among these pathogens are the flaviviruses, which include dengue virus and West Nile virus. Despite their medical importance, there are very few prophylactic or therapeutic treatments for these viruses. Moreover, the manner in which they subvert the innate immune response in order to establish infection in mammalian cells is not well understood. Recently, peroxisomes were reported to function in early antiviral signaling, but

Recurrence of CMV Infection and the Effect of Prolonged Antivirals in Organ Transplant Recipients.

PubMed

Natori, Yoichiro; Humar, Atul; Husain, Shahid; Rotstein, Coleman; Renner, Eberhard; Singer, Lianne; Kim, S Joseph; Kumar, Deepali

2017-06-01

Although initial therapy for cytomegalovirus (CMV) is usually successful, a significant subset of patients may have recurrent viremia. However, the epidemiology and risk factors for recurrence have not been fully defined, as well as the utility of prolonged antivirals after initial clearance. Solid organ transplant patients with first episode of CMV disease or asymptomatic viremia (≥1000 IU/mL) requiring treatment were identified by chart review. Clinical and virologic data were collected. The primary outcome was recurrence of CMV viremia or disease within 6 months of treatment discontinuation. The first episode of CMV viremia requiring antiviral therapy was assessed in 282 patients (147 CMV disease and 135 asymptomatic viremia). Cytomegalovirus occurred at 5.6 (0.63-27.7) months posttransplant. Recurrent CMV occurred in 30.5% patients at a median of 51 (0-160) days after discontinuation of therapy. Factors predictive of recurrence were treatment phase viral kinetics (P = 0.005), lung transplant (P = 0.002), CMV donor (D)+/recipient (R)- serostatus(P = 0.04) and recent acute rejection(P = 0.02). Prolonged antiviral therapy was given to 226 (80.1%) of 282 patients. Recurrence occurred in 73 (32.3%) of 226 patients that received prolonged antivirals versus 13 (23.2%) of 56 in those with no prolonged antivirals (P = 0.19). Recurrent CMV occurs in a significant percentage of patients after treatment of the first episode of CMV viremia/disease. CMV D+/R- serostatus, lung transplant, and treatment phase viral kinetics were significant predictors of recurrence. Continuation of prolonged antivirals beyond initial clearance was not associated with a reduced risk of recurrence.

[Impact of antiviral therapy on the natural history of hepatitis C virus].

PubMed

Fernández Rodriguez, Conrado M; Gutierrez Garcia, Maria Luisa

2014-12-01

Chronic hepatitis C virus infection affects around 150 million persons, and 350,000 persons worldwide die of this disease each year. Although the data on its natural history are incomplete, after the acute infection, most patients develop chronic forms of hepatitis C with variable stages of fibrosis. In these patients, continual inflammatory activity can cause significant fibrosis, cirrhosis, decompensation of the liver disease, or hepatocarcinoma. In the next few years, it is expected that hepatitis C virus infection and its complications will significantly increase, as will the incidence of hepatocarcinoma in Spain. This review presents the data on the natural history of hepatitis C virus infection and discusses the potential impact of antiviral therapy on the distinct stages of the disease. Copyright © 2014 Elsevier España, S.L.U. and AEEH y AEG. All rights reserved.

Targeted therapy in esophageal cancer.

PubMed

Zhang, Lei; Ma, Jiaojiao; Han, Yu; Liu, Jinqiang; Zhou, Wei; Hong, Liu; Fan, Daiming

2016-01-01

An increasing number of patients are diagnosed with esophageal cancer at an advanced stages, and only a small group of them can benefit from the traditional chemotherapy and radiotherapy. So far, multiple monoclonal antibodies and tyrosine kinase inhibitors have been developed, alone or in combination with traditional therapy, to improve the prognosis of patients with advanced esophageal cancer. This review summarizes the recent advances of targeted therapies against EGFR, HER2, VEGFR and c-MET in esophageal cancer. More clinical trials should be performed to evaluate the efficacy and safety of various targeted therapy regimens. Future basic research should focus on investigating the molecular mechanisms of therapeutic targets in esophageal cancer.

Spectroscopic investigation of herpes simplex viruses infected cells and their response to antiviral therapy

NASA Astrophysics Data System (ADS)

Erukhimovitch, Vitaly; Talyshinsky, Marina; Souprun, Yelena; Huleihel, Mahmoud

2006-07-01

In the present study, we used microscopic Fourier transform infrared spectroscopy (FTIR) to evaluate the antiviral activity of known antiviral agents against herpes viruses. The antiviral activity of Caffeic acid phenethyl ester (CAPE) (which is an active compound of propolis) against herpes simplex type 1 and 2 was examined in cell culture. The advantage of microscopic FTIR spectroscopy over conventional FTIR spectroscopy is that it facilitates inspection of restricted regions of cell culture or tissue. Our results showed significant spectral differences at early stages of infection between infected and non-infected cells, and between infected cells treated with the used antiviral agent and those not treated. In infected cells, there was a considerable increase in phosphate levels. Our results show that treatment with used antiviral agent considerably abolish the spectral changes induced by the viral infection. In addition, it is possible to track by FTIR microscopy method the deferential effect of various doses of the drug.

An antiviral RISC isolated from Tobacco rattle virus-infected plants

PubMed Central

Ciomperlik, Jessica J.; Omarov, Rustem T.; Scholthof, Herman B.

2011-01-01

The RNAi model predicts that during antiviral defense a RNA-induced silencing complex (RISC) is programmed with viral short-interfering RNAs (siRNAs) to target the cognate viral RNA for degradation. We show that infection of Nicotiana benthamiana with Tobacco rattle virus (TRV) activates an antiviral nuclease that specifically cleaves TRV RNA in vitro. In agreement with known RISC properties, the nuclease activity was inhibited by NaCl and EDTA and stimulated by divalent metal cations; a novel property was its preferential targeting of elongated RNA molecules. Intriguingly, the specificity of the TRV RISC could be re-programmed by exogenous addition of RNA (containing siRNAs) from plants infected with an unrelated virus, resulting in a newly acquired ability of RISC to target this heterologous genome in vitro. Evidently the virus-specific nuclease complex from N. benthamiana represents a genuine RISC that functions as a readily employable and reprogrammable antiviral defense unit. PMID:21272908

An antiviral RISC isolated from Tobacco rattle virus-infected plants.

PubMed

Ciomperlik, Jessica J; Omarov, Rustem T; Scholthof, Herman B

2011-03-30

The RNAi model predicts that during antiviral defense a RNA-induced silencing complex (RISC) is programmed with viral short-interfering RNAs (siRNAs) to target the cognate viral RNA for degradation. We show that infection of Nicotiana benthamiana with Tobacco rattle virus (TRV) activates an antiviral nuclease that specifically cleaves TRV RNA in vitro. In agreement with known RISC properties, the nuclease activity was inhibited by NaCl and EDTA and stimulated by divalent metal cations; a novel property was its preferential targeting of elongated RNA molecules. Intriguingly, the specificity of the TRV RISC could be reprogrammed by exogenous addition of RNA (containing siRNAs) from plants infected with an unrelated virus, resulting in a newly acquired ability of RISC to target this heterologous genome in vitro. Evidently the virus-specific nuclease complex from N. benthamiana represents a genuine RISC that functions as a readily employable and reprogrammable antiviral defense unit. Copyright © 2011 Elsevier Inc. All rights reserved.

The growth and potential of human antiviral monoclonal antibody therapeutics.

PubMed

Marasco, Wayne A; Sui, Jianhua

2007-12-01

Monoclonal antibodies (mAbs) have long provided powerful research tools for virologists to understand the mechanisms of virus entry into host cells and of antiviral immunity. Even so, commercial development of human (or humanized) mAbs for the prophylaxis, preemptive and acute treatment of viral infections has been slow. This is surprising, as new antibody discovery tools have increased the speed and precision with which potent neutralizing human antiviral mAbs can be identified. As longstanding barriers to antiviral mAb development, such as antigenic variability of circulating viral strains and the ability of viruses to undergo neutralization escape, are being overcome, deeper insight into the mechanisms of mAb action and engineering of effector functions are also improving the efficacy of antiviral mAbs. These successes, in both industrial and academic laboratories, coupled with ongoing changes in the biomedical and regulatory environments, herald an era when the commercial development of human antiviral mAb therapies will likely surge.

Targeted therapies: a nursing perspective.

PubMed

Kay, Polly

2006-02-01

To review the development of targeted therapies and the biology of relevant therapeutic targets. To analyze the relevance of targeted agents as part of current clinical practice. Research articles. Several targeted agents are now available for clinical use. Their mechanisms of action are more specific against tumor cells than traditional cytotoxics. Monotherapy regimens based on targeted agents tend to be better tolerated than chemotherapy, and most combination regimens with targeted agents have proven feasible. Their availability has greatly expanded cancer treatment options, especially for chemorefractory patients. Nurses involved in the care of patients with cancer can benefit from an increased understanding of targeted therapies, including their mechanisms of action, their efficacy profile, as well as prophylaxis and management of adverse events and administration procedures.

Successful Treatment of Corticosteroid with Antiviral Therapy for a Neonatal Liver Failure with Disseminated Herpes Simplex Virus Infection

PubMed Central

Maeba, Shinji; Hasegawa, Shunji; Shimomura, Maiko; Ichimura, Takuya; Takahashi, Kazumasa; Motoyama, Masashi; Fukunaga, Shinnosuke; Ito, Yoshinori; Ichiyama, Takashi; Ohga, Shouichi

2015-01-01

Background Herpes simplex virus (HSV) infection carries one of the poorest outcomes of neonatal liver failure (NLF). Neonates with disseminated HSV infection can develop hemophagocytic lymphohistiocytosis (HLH), and occasionally need orthotopic liver transplantation. Early interventions may be critical for the cure of NLF. Case Report We describe herewith a 6-day-old neonate with fulminant hepatic failure due to disseminated HSV-1 infection, who successfully responded to high-dose corticosteroid therapy 72 hours after the onset of disease. Preceding acyclovir, gamma globulin, and exchange blood transfusion therapies failed to control the disease. Methylprednisolone pulse therapy led to a drastic improvement of liver function and cytokine storms, and prevented the disease progression to HLH. Sustained levels of plasma and cerebrospinal fluid HSV DNA declined after prolonged acyclovir therapy. Bilateral lesions of the periventricular white matter areas, assessed by magnetic resonance imaging, disappeared at 3 months of age. The infant showed normal growth and development at 4 years of age. Conclusion Early anti-hypercytokinemia therapy using corticosteroid, and prolonged antiviral therapy might only provide the transplantation-free cure of NLF with HSV dissemination. PMID:26495160

Protein-Protein Interactions of Viroporins in Coronaviruses and Paramyxoviruses: New Targets for Antivirals?

PubMed Central

Torres, Jaume; Surya, Wahyu; Li, Yan; Liu, Ding Xiang

2015-01-01

Viroporins are members of a rapidly growing family of channel-forming small polypeptides found in viruses. The present review will be focused on recent structural and protein-protein interaction information involving two viroporins found in enveloped viruses that target the respiratory tract; (i) the envelope protein in coronaviruses and (ii) the small hydrophobic protein in paramyxoviruses. Deletion of these two viroporins leads to viral attenuation in vivo, whereas data from cell culture shows involvement in the regulation of stress and inflammation. The channel activity and structure of some representative members of these viroporins have been recently characterized in some detail. In addition, searches for protein-protein interactions using yeast-two hybrid techniques have shed light on possible functional roles for their exposed cytoplasmic domains. A deeper analysis of these interactions should not only provide a more complete overview of the multiple functions of these viroporins, but also suggest novel strategies that target protein-protein interactions as much needed antivirals. These should complement current efforts to block viroporin channel activity. PMID:26053927

Antiviral Goes Viral: Harnessing CRISPR/Cas9 to Combat Viruses in Humans.

PubMed

Soppe, Jasper Adriaan; Lebbink, Robert Jan

2017-10-01

The clustered regularly interspaced short palindromic repeats (CRISPR) and CRISPR-associated (Cas) systems are RNA-guided sequence-specific prokaryotic antiviral immune systems. In prokaryotes, small RNA molecules guide Cas effector endonucleases to invading foreign genetic elements in a sequence-dependent manner, resulting in DNA cleavage by the endonuclease upon target binding. A rewired CRISPR/Cas9 system can be used for targeted and precise genome editing in eukaryotic cells. CRISPR/Cas has also been harnessed to target human pathogenic viruses as a potential new antiviral strategy. Here, we review recent CRISPR/Cas9-based approaches to combat specific human viruses in humans and discuss challenges that need to be overcome before CRISPR/Cas9 may be used in the clinic as an antiviral strategy. Copyright © 2017 Elsevier Ltd. All rights reserved.

Perspective of Use of Antiviral Peptides against Influenza Virus

PubMed Central

Skalickova, Sylvie; Heger, Zbynek; Krejcova, Ludmila; Pekarik, Vladimir; Bastl, Karel; Janda, Jozef; Kostolansky, Frantisek; Vareckova, Eva; Zitka, Ondrej; Adam, Vojtech; Kizek, Rene

2015-01-01

The threat of a worldwide influenza pandemic has greatly increased over the past decade with the emergence of highly virulent avian influenza strains. The increased frequency of drug-resistant influenza strains against currently available antiviral drugs requires urgent development of new strategies for antiviral therapy, too. The research in the field of therapeutic peptides began to develop extensively in the second half of the 20th century. Since then, the mechanisms of action for several peptides and their antiviral prospect received large attention due to the global threat posed by viruses. Here, we discussed the therapeutic properties of peptides used in influenza treatment. Peptides with antiviral activity against influenza can be divided into three main groups. First, entry blocker peptides such as a Flupep that interact with influenza hemagglutinin, block its binding to host cells and prevent viral fusion. Second, several peptides display virucidal activity, disrupting viral envelopes, e.g., Melittin. Finally, a third set of peptides interacts with the viral polymerase complex and act as viral replication inhibitors such as PB1 derived peptides. Here, we present a review of the current literature describing the antiviral activity, mechanism and future therapeutic potential of these influenza antiviral peptides. PMID:26492266

Tangible resources for preparing patients for antiviral therapy for chronic hepatitis C.

PubMed

Bonner, Jason E; Barritt, A Sidney; Fried, Michael W; Evon, Donna M

2012-06-01

Chronic hepatitis C (HCV) infected patients with coexisting mental health and/or substance abuse issues face significant barriers to treatment and are often deferred. This paper sought to highlight critical pre-treatment strategies and provide tangible resources for HCV clinicians to facilitate preparation and successful treatment of these patients. Guided by the clinical experience of our liver center, a large, tertiary academic medical center, and informed by the extant literature, we summarize pre-treatment strategies and specific resources and recommendations for HCV providers. Four key pre-treatment strategies include: 1) screening for mental health/substance abuse issues using brief, reliable and validated instruments; 2) locating and establishing collaborative care with mental health and substance abuse specialists; 3) using a motivational interviewing communication style; and 4) addressing adherence-related issues. HCV clinicians are in a unique position to prepare patients with coexisting mental health and/or substance abuse issues for antiviral therapy.

Why are some HIV/AIDS patients reluctant to receive antiviral therapy as soon as possible in China?

PubMed

Sun, Yang; Lu, Hongzhou

2014-06-01

In more than 20 years of medical practice, a surprising phenomenon has often occurred: some patients with acquired immunodeficiency syndrome (AIDS) decide not to go to the hospital and they do not let others know that they are suffering from the disease unless they believe that they are dieing. Zhang Shan (a pseudonym) is one such patient with human immunodeficiency virus (HIV)/AIDS who was reluctant to receive antiviral therapy as soon as possible, and this paper shares Zhang's story as he related it. Clearly, there are numerous views as to why patients in China behave as Zhang did. Presented here are several reasons, including society, history, morality and ideology, family, and education. Although all of these reasons do play a role, the patient's mindset and behavior is the most significant reason for a patient's reluctance to seek treatment or disclose his/her status. If the individual patient's mindset and behavior are not dealt with effectively, then HIV/AIDS can continue to spread and threaten additional lives and even the fabric of society. This paper analyzes the reasons why patients are hesitant to receive antiviral therapy, but this paper also suggests steps healthcare personnel can take to encourage patients to seek treatment. Such steps can save the lives of current patients with HIV/AIDS. In addition, sound public health measures and a rational approach to treatment are important to helping potential patients with HIV/AIDS.

Targeted therapies for cancer

MedlinePlus

Targeted therapies are promising new treatments, but they have limitations. Cancer cells can become resistant to these drugs. The target sometimes changes, so the treatment no longer works. The cancer may find a different way to grow and survive that ...

High conservation of herpes simplex virus UL5/UL52 helicase-primase complex in the era of new antiviral therapies.

PubMed

Collot, Marianne; Rouard, Caroline; Brunet, Christel; Agut, Henri; Boutolleau, David; Burrel, Sonia

2016-04-01

The emergence of herpes simplex virus (HSV) resistance to current antiviral drugs, that all target the viral DNA polymerase, constitutes a major obstacle to antiviral treatment effectiveness of HSV infections, especially in immunocompromised patients. A novel and promising class of inhibitors of the HSV UL5/UL52 helicase-primase (HP) complex has been reported to hinder viral replication with a high potency. In this study, we describe the low natural polymorphism (interstrain identity >99.1% at both nucleotide and amino acid levels) of HSV HP complex subunits pUL5 and pUL52 among 64 HSV (32 HSV-1 and 32 HSV-2) clinical isolates, and we show that the HSV resistance profile to the first-line antiviral drug acyclovir (ACV) does not impact on the natural polymorphism of HSV HP complex. Genotypic tools and polymorphism data concerning HSV HP complex provided herein will be useful to detect drug resistance mutations in a relevant time frame when HP inhibitors (HPIs), i.e., amenamevir and pritelivir, will be available in medical practice. Copyright © 2016 Elsevier B.V. All rights reserved.

Host gene targets for novel influenza therapies elucidated by high-throughput RNA interference screens

PubMed Central

Meliopoulos, Victoria A.; Andersen, Lauren E.; Birrer, Katherine F.; Simpson, Kaylene J.; Lowenthal, John W.; Bean, Andrew G. D.; Stambas, John; Stewart, Cameron R.; Tompkins, S. Mark; van Beusechem, Victor W.; Fraser, Iain; Mhlanga, Musa; Barichievy, Samantha; Smith, Queta; Leake, Devin; Karpilow, Jon; Buck, Amy; Jona, Ghil; Tripp, Ralph A.

2012-01-01

Influenza virus encodes only 11 viral proteins but replicates in a broad range of avian and mammalian species by exploiting host cell functions. Genome-wide RNA interference (RNAi) has proven to be a powerful tool for identifying the host molecules that participate in each step of virus replication. Meta-analysis of findings from genome-wide RNAi screens has shown influenza virus to be dependent on functional nodes in host cell pathways, requiring a wide variety of molecules and cellular proteins for replication. Because rapid evolution of the influenza A viruses persistently complicates the effectiveness of vaccines and therapeutics, a further understanding of the complex host cell pathways coopted by influenza virus for replication may provide new targets and strategies for antiviral therapy. RNAi genome screening technologies together with bioinformatics can provide the ability to rapidly identify specific host factors involved in resistance and susceptibility to influenza virus, allowing for novel disease intervention strategies.—Meliopoulos, V. A., Andersen, L. E., Birrer, K. F., Simpson, K. J., Lowenthal, J. W., Bean, A. G. D., Stambas, J., Stewart, C. R., Tompkins, S. M., van Beusechem, V. W., Fraser, I., Mhlanga, M., Barichievy, S., Smith, Q., Leake, D., Karpilow, J., Buck, A., Jona, G., Tripp, R. A. Host gene targets for novel influenza therapies elucidated by high-throughput RNA interference screens. PMID:22247330

Significance of day-1 viral response of hepatitis C virus in patients with chronic hepatitis C receiving direct-acting antiviral therapy.

PubMed

Toyoda, Hidenori; Kumada, Takashi; Tada, Toshifumi; Yama, Tsuyoki; Mizuno, Kazuyuki

2018-06-01

On-treatment response of serum hepatitis C virus (HCV) is reportedly less useful to predict the outcome of anti-HCV therapy with interferon (IFN)-free regimen with direct-acting antivirals than with IFN-based regimens in clinical trials. We evaluated the significance of very early viral response after the start of therapy, which indicates direct HCV response to the drugs, on therapeutic outcome. Reductions in serum HCV-RNA levels were measured at 1 day after the start of therapy in 544 patients who underwent IFN-free direct-acting antiviral regimens. The association between these reductions and the achievement or failure of sustained virologic response (SVR) was evaluated. Patient characteristics did not influence 1-day reduction in serum HCV-RNA except for liver fibrosis. There was no difference in 1-day HCV reduction between SVR and non-SVR patients treated with a 24-week regimen. In contrast, in patients treated with a 12-week regimen, 1-day reduction was significantly greater in SVR than in non-SVR patients (P = 0.0013) and was predictive of SVR versus non-SVR (area under the receiver-operating characteristics curve: 0.80). Whereas the reduction in serum HCV-RNA levels at 1 day after the start of therapy was not associated with treatment outcomes in patients who underwent a 24-week regimen of IFN-free therapy, there was an association in patients receiving a 12-week regimen, and this reduction was predictive of SVR, thus potentially serving as a factor to identify patients at risk of treatment failure. © 2017 Journal of Gastroenterology and Hepatology Foundation and John Wiley & Sons Australia, Ltd.

Efficacy of antiviral therapy on hepatitis C recurrence after liver transplantation: a randomized controlled study.

PubMed

Carrión, José A; Navasa, Miquel; García-Retortillo, Montserrat; García-Pagan, Juan Carlos; Crespo, Gonzalo; Bruguera, Miquel; Bosch, Jaime; Forns, Xavier

2007-05-01

Recurrence of hepatitis C virus (HCV) infection is a relevant problem of liver transplantation programs. We evaluated the effect of antiviral therapy on disease progression in 81 HCV-infected liver transplantation recipients. Patients with mild hepatitis C recurrence (fibrosis stage F0 to F2, n = 54) were randomized to no treatment (group A, n = 27) or peginterferon alfa-2b/ribavirin for 48 weeks (group B, n = 27). Patients with severe recurrence (F3 to F4, cholestatic hepatitis) were treated (group C, n = 27). All patients (n = 81) underwent a liver biopsy at baseline and after follow-up; paired hepatic venous pressure gradient (HVPG) measurements were available in 51 patients. Thirteen (48%) patients of group B and 5 (18.5%) of group C achieved sustained virological response. Liver fibrosis progressed > or =1 stage in 40 (49%) of 81 patients: 19 (70%) of group A versus 7 (26%) of group B (P = .001) and in 14 (54%) of group C. HVPG increased (6.5 to 13 mm Hg, P < .01) in patients in whom fibrosis worsened, whereas it decreased (5 to 3.5 mm Hg, P = .017) or remained unchanged in those with fibrosis improvement or stabilization, respectively. The only variable independently associated with fibrosis improvement/stabilization was treatment (odds ratio [OR] =3.7, 95% confidence interval [CI] 1.3 to 10, P = .009). Among treated patients, alanine aminotransferase (ALT) normalization and viral clearance were independently associated with histological or hemodynamic improvement/stabilization (OR 5.3, 95% CI 1.5 to 18, P < .01; OR 7.4, 95% CI 1.4 to 38, P = .01; respectively). Our data demonstrate that in liver transplantation recipients, antiviral therapy slows disease progression (particularly in sustained virological responders), as shown by its effects on liver histology and on HVPG.

Systematic review with meta-analysis: recurrence of hepatocellular carcinoma following direct-acting antiviral therapy.

PubMed

Saraiya, N; Yopp, A C; Rich, N E; Odewole, M; Parikh, N D; Singal, A G

2018-05-30

Although studies suggest decreased incident hepatocellular carcinoma (HCC) after direct-acting antivirals (DAA), data are conflicting regarding HCC recurrence and aggressiveness in patients who have a history of HCC with complete response. Characterize HCC recurrence patterns after DAA therapy. Two reviewers searched MEDLINE and SCOPUS from January 2015 to December 2017 and identified studies evaluating HCC recurrence patterns following DAA therapy. A pooled estimate was calculated using the DerSimonian and Laird method for a random effects model. The study was conducted in accordance with PRISMA guidelines. Among 24 studies (n = 1820 patients), the proportion of patients with HCC recurrence following DAA therapy ranged from 0% to 59% (pooled estimate 24.4%; 95% CI: 18.4%-30.4%). Among 11 full text manuscripts, pooled HCC recurrence was 21.9% (95% CI: 16.2%-28.3%). Factors associated with recurrence included history of prior HCC recurrence and a shorter interval between HCC complete response and DAA initiation. Nine studies comparing DAA-treated and interferon-treated or untreated patients found similar recurrence among DAA-treated patients. Most (77.8%) patients with HCC recurrence were detected at an early tumour stage, of whom 64.7% received curative treatment. Study limitations included heterogeneous cohorts, potential misclassification of HCC absence prior to DAA, ascertainment bias for recurrence, and short durations of follow-up. Current data suggest acceptable HCC recurrence rates after DAA therapy, particularly if DAA therapy is delayed at least 6 months after HCC complete response. However, data characterising HCC recurrence after DAA therapy are of limited quality, highlighting the need for high quality prospective studies. © 2018 John Wiley & Sons Ltd.

Molecular Mechanisms of Foot-and-Mouth Disease Virus Targeting the Host Antiviral Response.

PubMed

Rodríguez Pulido, Miguel; Sáiz, Margarita

2017-01-01

Foot-and-mouth disease virus (FMDV) is the causative agent of an acute vesicular disease affecting pigs, cattle and other domestic, and wild animals worldwide. The aim of the host interferon (IFN) response is to limit viral replication and spread. Detection of the viral genome and products by specialized cellular sensors initiates a signaling cascade that leads to a rapid antiviral response involving the secretion of type I- and type III-IFNs and other antiviral cytokines with antiproliferative and immunomodulatory functions. During co-evolution with their hosts, viruses have acquired strategies to actively counteract host antiviral responses and the balance between innate response and viral antagonism may determine the outcome of disease and pathogenesis. FMDV proteases Lpro and 3C have been found to antagonize the host IFN response by a repertoire of mechanisms. Moreover, the putative role of other viral proteins in IFN antagonism is being recently unveiled, uncovering sophisticated immune evasion strategies different to those reported to date for other members of the Picornaviridae family. Here, we review the interplay between antiviral responses induced by FMDV infection and viral countermeasures to block them. Research on strategies used by viruses to modulate immunity will provide insights into the function of host pathways involved in defense against pathogens and will also lead to development of new therapeutic strategies to fight virus infections.

New targeted therapies in pancreatic cancer.

PubMed

Seicean, Andrada; Petrusel, Livia; Seicean, Radu

2015-05-28

Patients with pancreatic cancer have a poor prognosis with a median survival of 4-6 mo and a 5-year survival of less than 5%. Despite therapy with gemcitabine, patient survival does not exceed 6 mo, likely due to natural resistance to gemcitabine. Therefore, it is hoped that more favorable results can be obtained by using guided immunotherapy against molecular targets. This review summarizes the new leading targeted therapies in pancreatic cancers, focusing on passive and specific immunotherapies. Passive immunotherapy may have a role for treatment in combination with radiochemotherapy, which otherwise destroys the immune system along with tumor cells. It includes mainly therapies targeting against kinases, including epidermal growth factor receptor, Ras/Raf/mitogen-activated protein kinase cascade, human epidermal growth factor receptor 2, insulin growth factor-1 receptor, phosphoinositide 3-kinase/Akt/mTOR and hepatocyte growth factor receptor. Therapies against DNA repair genes, histone deacetylases, microRNA, and pancreatic tumor tissue stromal elements (stromal extracellular matric and stromal pathways) are also discussed. Specific immunotherapies, such as vaccines (whole cell recombinant, peptide, and dendritic cell vaccines), adoptive cell therapy and immunotherapy targeting tumor stem cells, have the role of activating antitumor immune responses. In the future, treatments will likely include personalized medicine, tailored for numerous molecular therapeutic targets of multiple pathogenetic pathways.

The interferon response circuit in antiviral host defense.

PubMed

Haller, O; Weber, F

2009-01-01

Viruses have learned to multiply in the face of a powerful innate and adaptive immune response of the host. They have evolved multiple strategies to evade the interferon (IFN) system which would otherwise limit virus growth at an early stage of infection. IFNs induce the synthesis of a range of antiviral proteins which serve as cell-autonomous intrinsic restriction factors. For example, the dynamin-like MxA GTPase inhibits the multiplication of influenza and bunyaviruses (such as La Crosse virus, Hantaan virus, Rift Valley Fever virus, and Crimean-Congo hemorrhagic fever virus) by binding and sequestering the nucleocapsid protein into large perinuclear complexes. To overcome such intracellular restrictions, virulent viruses either inhibit IFN synthesis, bind and inactivate secreted IFN molecules, block IFN-activated signaling, or disturb the action of IFN-induced antiviral proteins. Many viruses produce specialized proteins to disarm the danger signal or express virulence genes that target members of the IFN regulatory factor family (IRFs) or components of the JAK-STAT signaling pathway. An alternative evasion strategy is based on extreme viral replication speed which out-competes the IFN response. The identification of viral proteins with IFN antagonistic functions has great implications for disease prevention and therapy. Virus mutants lacking IFN antagonistic properties represent safe yet highly immunogenic candidate vaccines. Furthermore, novel drugs intercepting viral IFN-antagonists could be used to disarm the viral intruders.

Type I interferon-mediated autoimmune diseases: pathogenesis, diagnosis and targeted therapy.

PubMed

Psarras, Antonios; Emery, Paul; Vital, Edward M

2017-10-01

Type I interferons (IFN-Is) are a group of molecules with pleiotropic effects on the immune system forming a crucial link between innate and adaptive immune responses. Apart from their important role in antiviral immunity, IFN-Is are increasingly recognized as key players in autoimmune CTDs such as SLE. Novel therapies that target IFN-I appear effective in SLE in early trials, but effectiveness is related to the presence of IFN-I biomarkers. IFN-I biomarkers may also act as positive or negative predictors of response to other biologics. Despite the high failure rate of clinical trials in SLE, subgroups of patients often respond better. Fully optimizing the potential of these agents is therefore likely to require stratification of patients using IFN-I and other biomarkers. This suggests the unified concept of type I IFN-mediated autoimmune diseases as a grouping including patients with a variety of different traditional diagnoses. © The Author 2017. Published by Oxford University Press on behalf of the British Society for Rheumatology. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Oligonucleotides as antivirals: dream or realistic perspective?

PubMed

Van Aerschot, Arthur

2006-09-01

Many reports have been published on antiviral activity of synthetic oligonucleotides, targeted to act either by a true antisense effect or via non-sequence specific interactions. This short review will try to evaluate the current status of the field by focusing on the effects as reported for inhibition of either HSV-1, HCMV or HIV-1. Following an introduction with a historical background and a brief discussion on the different types of constructs and mechanisms of action, the therapeutic potential of antisense oligonucleotides as antivirals, as well as possible pitfalls upon their evaluation will be discussed.

Long-term liver stiffness assessment in hepatitis C virus patients undergoing antiviral therapy: Results from a 5-year cohort study.

PubMed

Facciorusso, Antonio; Del Prete, Valentina; Turco, Antonio; Buccino, Rosario Vincenzo; Nacchiero, Maurizio Cosimo; Muscatiello, Nicola

2018-04-01

Observational studies showed significant liver stiffness regression after sustained virological response, but long-term effects of antiviral therapy are still unknown. The aim of this study was to assess the magnitude of change in stiffness up to 5 years after therapy in hepatitis C patients undergoing antiviral treatment. Data of 153 patients were retrieved. Stiffness was assessed by Fibroscan at baseline, end of treatment, 6 months after treatment, and every year hereafter up to 5 years. Seventy patients were treated with interferon-based regimens and 83 with direct antiviral agents. Baseline cirrhosis was diagnosed in 53 (34.6%) patients. Sustained virological response was achieved in 112 patients, whereas 41 were non-responders. In responders, stiffness decreased from 12.3 kPa (9-17.8) to 6.6 kPa (5.3-7.4) at 5 years. A sharper decline was observed immediately after treatment (-2.5 kPa at the end of treatment and -3.7 kPa at 6 months), while from 1 year onwards, the magnitude of stiffness decrease was progressively lower. In non-responders, stiffness showed a slight decrease at the end of treatment (from 19.2 to 18.1 kPa), then returned to baseline levels at 6 months (19.4 kPa), and finally increased over time up to 23.7 kPa (15-32.5) at 5 years. The proportion of cirrhotic patients decreased by 50% at 6 months and finally fell < 5% at 4 years after treatment. Stiffness declines significantly after achieving response, and the magnitude of decline is greater in the first year after treatment, while it tends to plateau from 1 year onwards. © 2017 Journal of Gastroenterology and Hepatology Foundation and John Wiley & Sons Australia, Ltd.

IFN-stimulated gene 15 functions as a critical antiviral molecule against influenza, herpes, and Sindbis viruses

PubMed Central

Lenschow, Deborah J.; Lai, Caroline; Frias-Staheli, Natalia; Giannakopoulos, Nadia V.; Lutz, Andrew; Wolff, Thorsten; Osiak, Anna; Levine, Beth; Schmidt, Robert E.; García-Sastre, Adolfo; Leib, David A.; Pekosz, Andrew; Knobeloch, Klaus-Peter; Horak, Ivan; Virgin, Herbert Whiting

2007-01-01

Type I interferons (IFNs) play an essential role in the host response to viral infection through the induction of numerous IFN-stimulated genes (ISGs), including important antiviral molecules such as PKR, RNase L, Mx, and iNOS. Yet, additional antiviral ISGs likely exist. IFN-stimulated gene 15 (ISG15) is a ubiquitin homolog that is rapidly up-regulated after viral infection, and it conjugates to a wide array of host proteins. Although it has been hypothesized that ISG15 functions as an antiviral molecule, the initial evaluation of ISG15-deficient mice revealed no defects in their responses to vesicular stomatitis virus or lymphocytic choriomeningitis virus, leaving open the important question of whether ISG15 is an antiviral molecule in vivo. Here we demonstrate that ISG15 is critical for the host response to viral infection. ISG15−/− mice are more susceptible to influenza A/WSN/33 and influenza B/Lee/40 virus infections. ISG15−/− mice also exhibited increased susceptibility to both herpes simplex virus type 1 and murine gammaherpesvirus 68 infection and to Sindbis virus infection. The increased susceptibility of ISG15−/− mice to Sindbis virus infection was rescued by expressing wild-type ISG15, but not a mutant form of ISG15 that cannot form conjugates, from the Sindbis virus genome. The demonstration of ISG15 as a novel antiviral molecule with activity against both RNA and DNA viruses provides a target for the development of therapies against important human pathogens. PMID:17227866

Immunosuppressive and antiviral treatment of hepatitis C virus-associated glomerular disease: A long-term follow-up.

PubMed

Fabrizi, Fabrizio; Aghemo, Alessio; Lampertico, Pietro; Fraquelli, Mirella; Cresseri, Donata; Moroni, Gabriella; Passerini, Patrizia; Donato, Francesca M; Messa, Piergiorgio

2018-06-01

The evidence in the medical literature on the treatment of hepatitis C virus-associated glomerular disease is extremely limited. The advent of nonconventional immunosuppressive agents and direct-acting antivirals promises high efficacy and safety. We conducted an open-label, single-arm clinical study to examine the efficacy and safety of a combined approach for hepatitis C virus-associated glomerular disease. In the first phase of the study, patients with hepatitis C virus-associated glomerular disease received interferon-based antiviral therapy and immunosuppressive agents; since 2013, interferon-free antiviral therapy was adopted and novel immunosuppressants (including B-cell depleting agents and mycophenolate mofetil) or immunomodulators (ribavirin) were choiced. Virological and clinical responses were evaluated over a long observation period (median follow-up of 60 weeks and 46.5 months after the end of treatment with interferon and direct-acting antiviral agents, respectively). We enrolled 25 consecutive patients with hepatitis C virus-associated glomerular disease, 8 being liver transplant recipients for hepatitis C. A total of 13 patients received therapy with direct-acting antivirals and experienced sustained viral response (serum hepatitis C virus RNA <12 IU/mL, 12 weeks after treatment ended, sustained viral response12). The mean (±standard deviation) proteinuria decreased from 2.61 ± 1.01 at baseline to 1.71 ± 1.43 (g/day) at sustained viral response 48, p = 0.031; microscopic hematuria and serum cryoglobulins disappeared in six (50%) and seven (64%) patients, respectively, after sustained viral response by direct-acting antivirals. Adverse events occurred in 69% (9/13) of patients and were mild, with four cases of ribavirin-related anemia requiring blood transfusions (no drop-outs). After sustained viral response by direct-acting antivirals, immunosuppressive and immunomodulatory agents were initiated in clinical relapsers ( n = 2) and nonresponders

Structure-based lead optimization to improve antiviral potency and ADMET properties of phenyl-1H-pyrrole-carboxamide entry inhibitors targeted to HIV-1 gp120.

PubMed

Curreli, Francesca; Belov, Dmitry S; Kwon, Young Do; Ramesh, Ranjith; Furimsky, Anna M; O'Loughlin, Kathleen; Byrge, Patricia C; Iyer, Lalitha V; Mirsalis, Jon C; Kurkin, Alexander V; Altieri, Andrea; Debnath, Asim K

2018-05-12

We are continuing our concerted effort to optimize our first lead entry antagonist, NBD-11021, which targets the Phe43 cavity of the HIV-1 envelope glycoprotein gp120, to improve antiviral potency and ADMET properties. In this report, we present a structure-based approach that helped us to generate working hypotheses to modify further a recently reported advanced lead entry antagonist, NBD-14107, which showed significant improvement in antiviral potency when tested in a single-cycle assay against a large panel of Env-pseudotyped viruses. We report here the synthesis of twenty-nine new compounds and evaluation of their antiviral activity in a single-cycle and multi-cycle assay to derive a comprehensive structure-activity relationship (SAR). We have selected three inhibitors with the high selectivity index for testing against a large panel of 55 Env-pseudotyped viruses representing a diverse set of clinical isolates of different subtypes. The antiviral activity of one of these potent inhibitors, 55 (NBD-14189), against some clinical isolates was as low as 63 nM. We determined the sensitivity of CD4-binding site mutated-pseudoviruses to these inhibitors to confirm that they target HIV-1 gp120. Furthermore, we assessed their ADMET properties and compared them to the clinical candidate attachment inhibitor, BMS-626529. The ADMET data indicate that some of these new inhibitors have comparable ADMET properties to BMS-626529 and can be optimized further to potential clinical candidates. Copyright © 2018 Elsevier Masson SAS. All rights reserved.

What is the impact of a country-wide scale-up in antiviral therapy on the characteristics and sustained viral response rates of patients treated for hepatitis C?

PubMed

McDonald, Scott A; Innes, Hamish A; Hayes, Peter C; Dillon, John F; Mills, Peter R; Goldberg, David J; Barclay, Stephen; Allen, Sam; Fox, Ray; Fraser, Andrew; Kennedy, Nicholas; Bhattacharyya, Diptendu; Hutchinson, Sharon J

2015-02-01

The global burden associated with hepatitis C virus (HCV) infection has prompted a scale-up of antiviral therapy. Hitherto, no data exist on the impact of scaling-up, on the characteristics of treated populations, or on sustained viral response (SVR) rates. We assessed the country-wide scale-up of antiviral therapy in Scotland, a country which nationally monitors uptake of and response to HCV treatment. Data for patients, initiated on combined pegylated interferon and ribavirin therapy at 13 specialist HCV clinics in 2001-2010, were extracted from the Scottish HCV Clinical Database (n=3895). Patient characteristics included age, genotype, PWID (people who inject drugs) status, prison referral, and diagnosed cirrhosis. Temporal trends in covariates and adjusted effects on a SVR were examined via mixed-effects regression. The number of patients starting treatment increased from 237 in 2001-2002 to 1560 in 2009-2010, with an increasing trend in SVR from 44% to 57% over this period. For a given clinic, between 2001/2 and 2010 there was a decrease in the odds of those treated being diagnosed with cirrhosis (odds ratio [OR]=0.84 per year), and increasing temporal trends for those treated being PWID (OR=1.08) and prison referrals (OR=1.06). Adjusting for covariates, the proportion of a given clinic's patients achieving SVR was positively associated with the percentage of PWID (OR=1.01 per percent increase; 95% confidence interval [CI]: 1.00-1.02) and genotype 2/3 (OR=1.03; 95% CI: 1.02-1.04). Despite changes in patient characteristics, a country-wide scale-up of antiviral therapy did not compromise SVR rates. Results are highly relevant to countries planning on scaling-up treatment, given the forthcoming availability of new interferon-free therapies. Copyright © 2014 European Association for the Study of the Liver. Published by Elsevier B.V. All rights reserved.

Examining Hepatitis, A and B Vaccination, and HBV Reactivation Monitoring During Direct-Acting Antiviral Therapy for Hepatitis C.

PubMed

Davison, John; O'Shea, Amy; Waterbury, Nancee; Villalvazo, Yolanda

2018-05-30

The objective of this study was to examine Hepatitis A (HAV) and Hepatitis B (HBV) screening, and the risk of HBV reactivation during Hepatitis C (HCV) therapy with direct-acting antivirals (DAAs). A retrospective chart review was performed of patients treated with second generation DAA therapy from January 2014 to September 2016 at the Iowa City VA Healthcare System. In total 409 patients initiated HCV treatment, 308 (75%) and 241 (59%) were HAV and HBV vaccine eligible, respectively. Among those, 24 (8%) received a HAV vaccine, while only 20 (8%) received a HBV vaccine. Of these, 7 patients initiating an immunization in the clinic had record of completing the series. Further, 101 patients had a reactive Hepatitis B core Antibody indicating previous HBV infection, and 3 of these were tested for HBV reactivation during HCV therapy. Overall, the assessment found low rates of HAV and HBV vaccine administration, indicating missed opportunities for preventative care during HCV therapy. With the known risk of HBV reactivation with DAAs, the need for HAV and HBV screening is essential.

Steroid/Antiviral for the treatment of Bell's palsy: Double blind randomized clinical trial.

PubMed

Khedr, Eman Mohamed; Badry, Reda; Ali, Anwer Mohamed; Abo El-Fetoh, Noha; El-Hammady, Dina Hatem; Ghandour, Abeer Mohamed; Abdel-Haleem, Ahmed

2016-11-22

A large number of patients with Bell's palsy fail to recover facial function completely after steroid therapy. Only a few small trials have been conducted to test whether outcomes can be improved by the addition of antiviral therapy. To evaluate the efficacy of treatment with steroid alone versus steroid + antiviral in a group of patients with moderately severe to severe acute Bell's palsy. Fifty eligible patients out of a total of 65 with acute onset Bell's palsy were randomized to receive the two treatments. Evaluation was performed before starting treatment, after 2 weeks of treatment and 3 months after onset, using the House and Brackmann facial nerve grading system (HB) and the Sunnybrook grading system.This study was registered with ClinicalTrials.gov, number NCT02328079. Both treatments had comparable demographics and clinical scores at baseline. There was greater improvement in the mean HB and Sunnybrook scores of the steroid + antiviral group in comparison to steroid group at 3 months. At the end of the 3rd month, 17 patients (68%) had good recovery and 8 patients (32%) had poor recovery in the steroid group compared with 23 patients (92%) and 2 (8%) respectively in the steroid and antiviral group (p = 0.034). The combination of steroid and antiviral treatment increases the possibility of recovery in moderately severe to complete acute Bell's palsy.

Molecular targets for flavivirus drug discovery

PubMed Central

Sampath, Aruna; Padmanabhan, R.

2009-01-01

Flaviviruses are a major cause of infectious disease in humans. Dengue virus causes an estimated 50 million cases of febrile illness each year, including an increasing number of cases of hemorrhagic fever. West Nile virus, which recently spread from the Mediterranean basin to the Western Hemisphere, now causes thousands of sporadic cases of encephalitis annually. Despite the existence of licensed vaccines, yellow fever, Japanese encephalitis and tick-borne encephalitis also claim many thousands of victims each year across their vast endemic areas. Antiviral therapy could potentially reduce morbidity and mortality from flavivirus infections, but no effective drugs are currently available. This article introduces a collection of papers in Antiviral Research on molecular targets for flavivirus antiviral drug design and murine models of dengue virus disease that aims to encourage drug development efforts. After reviewing the flavivirus replication cycle, we discuss the envelope glycoprotein, NS3 protease, NS3 helicase, NS5 methyltransferase and NS5 RNA-dependent RNA polymerase as potential drug targets, with special attention being given to the viral protease. The other viral proteins are the subject of individual articles in the journal. Together, these papers highlight current status of drug discovery efforts for flavivirus diseases and suggest promising areas for further research. PMID:18796313

Decision making with regard to antiviral intervention during an influenza pandemic.

PubMed

Shim, Eunha; Chapman, Gretchen B; Galvani, Alison P

2010-01-01

Antiviral coverage is defined by the proportion of the population that takes antiviral prophylaxis or treatment. High coverage of an antiviral drug has epidemiological and evolutionary repercussions. Antivirals select for drug resistance within the population, and individuals may experience adverse effects. To determine optimal antiviral coverage in the context of an influenza outbreak, we compared 2 perspectives: 1) the individual level (the Nash perspective), and 2) the population level (utilitarian perspective). We developed an epidemiological game-theoretic model of an influenza pandemic. The data sources were published literature and a national survey. The target population was the US population. The time horizon was 6 months. The perspective was individuals and the population overall. The interventions were antiviral prophylaxis and treatment. The outcome measures were the optimal coverage of antivirals in an influenza pandemic. At current antiviral pricing, the optimal Nash strategy is 0% coverage for prophylaxis and 30% coverage for treatment, whereas the optimal utilitarian strategy is 19% coverage for prophylaxis and 100% coverage for treatment. Subsidizing prophylaxis by $440 and treatment by $85 would bring the Nash and utilitarian strategies into alignment. For both prophylaxis and treatment, the optimal antiviral coverage decreases as pricing of antivirals increases. Our study does not incorporate the possibility of an effective vaccine and lacks probabilistic sensitivity analysis. Our survey also does not completely represent the US population. Because our model assumes a homogeneous population and homogeneous antiviral pricing, it does not incorporate heterogeneity of preference. The optimal antiviral coverage from the population perspective and individual perspectives differs widely for both prophylaxis and treatment strategies. Optimal population and individual strategies for prophylaxis and treatment might be aligned through subsidization.

Direct-acting antiviral therapy decreases hepatocellular carcinoma recurrence rate in cirrhotic patients with chronic hepatitis C.

PubMed

Virlogeux, Victor; Pradat, Pierre; Hartig-Lavie, Kerstin; Bailly, François; Maynard, Marianne; Ouziel, Guillaume; Poinsot, Domitille; Lebossé, Fanny; Ecochard, Marie; Radenne, Sylvie; Benmakhlouf, Samir; Koffi, Joseph; Lack, Philippe; Scholtes, Caroline; Uhres, Anne-Claire; Ducerf, Christian; Mabrut, Jean-Yves; Rode, Agnès; Levrero, Massimo; Combet, Christophe; Merle, Philippe; Zoulim, Fabien

2017-08-01

Arrival of direct-acting antiviral agents against hepatitis C virus with high-sustained virological response rates and very few side effects has drastically changed the management of hepatitis C virus infection. The impact of direct-acting antiviral exposure on hepatocellular carcinoma recurrence after a first remission in patients with advanced fibrosis remains to be clarified. 68 consecutive hepatitis C virus patients with a first hepatocellular carcinoma diagnosis and under remission, subsequently treated or not with a direct-acting antiviral combination, were included. Clinical, biological and virological data were collected at first hepatocellular carcinoma diagnosis, at remission and during the surveillance period. All patients were cirrhotic. Median age was 62 years and 76% of patients were male. Twenty-three patients (34%) were treated with direct-acting antivirals and 96% of them achieved sustained virological response. Median time between hepatocellular carcinoma remission and direct-acting antivirals initiation was 7.2 months (IQR: 3.6-13.5; range: 0.3-71.4) and median time between direct-acting antivirals start and hepatocellular carcinoma recurrence was 13.0 months (IQR: 9.2-19.6; range: 3.0-24.7). Recurrence rate was 1.7/100 person-months among treated patients vs 4.2/100 person-months among untreated patients (P=.008). In multivariate survival analysis, the hazard ratio for hepatocellular carcinoma recurrence after direct-acting antivirals exposure was 0.24 (95% confidence interval: 0.10-0.55; P<.001). Hepatocellular carcinoma recurrence rate was significantly lower among patients treated with direct-acting antivirals compared with untreated patients. Given the potential impact of our observation, large-scale prospective cohort studies are needed to confirm these results. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Targeted therapy in lung cancer: IPASS and beyond, keeping abreast of the explosion of targeted therapies for lung cancer

PubMed Central

Savas, Peter; Hughes, Brett

2013-01-01

Advances in the treatment of non-small cell lung cancer (NSCLC) over the last decade have predominantly involved the development of therapies directed at molecular targets such as mutations in the epidermal growth factor receptor (EGFR) or rearrangements in the anaplastic lymphoma kinase (ALK) gene. Other targets have been discovered at low frequency, with multiple agents approved or in development for treatment of these rare molecular subtypes. The tumour microenvironment has also provided opportunities for therapies targeting angiogenesis and the host immune response. This review will provide an overview of current targeted therapies in NSCLC and promising treatment approaches on the horizon. PMID:24163750

The SARS-Coronavirus papain-like protease: Structure, function and inhibition by designed antiviral compounds

PubMed Central

Baez-Santos, Yahira M.; St. John, Sarah E.; Mesecar, Andrew D.

2018-01-01

Over ten years have passed since the deadly human coronavirus that causes severe acute respiratory syndrome (SARS-CoV) emerged from the Guangdong Province of China. Despite the fact that the SARS-CoV pandemic infected over 8,500 individuals, claimed over 800 lives and cost billions of dollars in economic loss worldwide, there still are no clinically approved antiviral drugs, vaccines or monoclonal antibody therapies to treat SARS-CoV infections. The recent emergence of the deadly human coronavirus that causes Middle East respiratory syndrome (MERS-CoV) is a sobering reminder that new and deadly coronaviruses can emerge at any time with the potential to become pandemics. Therefore, the continued development of therapeutic and prophylactic countermeasures to potentially deadly coronaviruses is warranted. The coronaviral proteases, papain-like protease (PLpro) and 3C-like protease (3CLpro), are attractive antiviral drug targets because they are essential for coronaviral replication. Although the primary function of PLpro and 3CLpro are to process the viral polyprotein in a coordinated manner, PLpro has the additional function of stripping ubiquitin and ISG15 from host-cell proteins to aid coronaviruses in their evasion of the host innate immune responses. Therefore, targeting PLpro with antiviral drugs may have an advantage in not only inhibiting viral replication but also inhibiting the dysregulation of signaling cascades in infected cells that may lead to cell death in surrounding, uninfected cells. This review provides an up-to-date discussion on the SARS-CoV papain-like protease including a brief overview of the SARS-CoV genome and replication followed by a more in-depth discussion on the structure and catalytic mechanism of SARS-CoV PLpro, the multiple cellular functions of SARS-CoV PLpro, the inhibition of SARS-CoV PLpro by small molecule inhibitors, and the prospect of inhibiting papain-like protease from other coronaviruses. This paper forms part of a series

Targeted Nanoparticles for Kidney Cancer Therapy

DTIC Science & Technology

2013-10-01

AD_________________ Award Number: W81XWH-10-1-0434 TITLE: Targeted Nanoparticles for Kidney Cancer Therapy PRINCIPAL...Targeted Nanoparticles for Kidney Cancer Therapy 5b. GRANT NUMBER W81XWH-10-1-0434 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) 5d. PROJECT...lines following treatment with D5 nanotubes. Tthermoablation will be studied initially. Human kidney cancer cells will be injected into the kidney

Treatment of norovirus infections: Moving antivirals from the bench to the bedside

PubMed Central

Kaufman, Stuart S.; Green, Kim Y.; Korba, Brent E.

2016-01-01

Noroviruses (NV) are the most common cause of acute gastrointestinal illness in the United States and worldwide. The development of specific antiviral countermeasures has lagged behind that of other viral pathogens, primarily because norovirus disease has been perceived as brief and self-limiting and robust assays suitable for drug discovery have been lacking. The increasing recognition that NV illness can be life-threatening, especially in immunocompromised patients who often require prolonged hospitalization and intensive supportive care, has stimulated new research to develop an effective antiviral therapy. Here, we propose a path forward for evaluating drug therapy in norovirus-infected immunocompromised individuals, a population at high risk for serious and prolonged illness. The clinical and laboratory features of norovirus illness in immunocompromised patients are reviewed, and potential markers of drug efficacy are defined. We discuss the potential design of clinical trials in these patients and how an anti-viral therapy that proves effective in immunocompromised patients might also be used in the setting of acute outbreaks, especially in confined settings such as nursing homes, to block the spread of infection and reduce the severity of illness. We conclude by reviewing the current status of approved and experimental compounds that might be evaluated in a hospital setting. PMID:24583027

Decision Making with Regard to Antiviral Intervention during an Influenza Pandemic

PubMed Central

Shim, Eunha; Chapman, Gretchen B.; Galvani, Alison P.

2012-01-01

Background Antiviral coverage is defined by the proportion of the population that takes antiviral prophylaxis or treatment. High coverage of an antiviral drug has epidemiological and evolutionary repercussions. Antivirals select for drug resistance within the population, and individuals may experience adverse effects. To determine optimal antiviral coverage in the context of an influenza outbreak, we compared 2 perspectives: 1) the individual level (the Nash perspective), and 2) the population level (utilitarian perspective). Methods We developed an epidemiological game-theoretic model of an influenza pandemic. The data sources were published literature and a national survey. The target population was the US population. The time horizon was 6 months. The perspective was individuals and the population overall. The interventions were antiviral prophylaxis and treatment. The outcome measures were the optimal coverage of antivirals in an influenza pandemic. Results At current antiviral pricing, the optimal Nash strategy is 0% coverage for prophylaxis and 30% coverage for treatment, whereas the optimal utilitarian strategy is 19% coverage for prophylaxis and 100% coverage for treatment. Subsidizing prophylaxis by $440 and treatment by $85 would bring the Nash and utilitarian strategies into alignment. For both prophylaxis and treatment, the optimal antiviral coverage decreases as pricing of antivirals increases. Our study does not incorporate the possibility of an effective vaccine and lacks probabilistic sensitivity analysis. Our survey also does not completely represent the US population. Because our model assumes a homogeneous population and homogeneous antiviral pricing, it does not incorporate heterogeneity of preference. Conclusions The optimal antiviral coverage from the population perspective and individual perspectives differs widely for both prophylaxis and treatment strategies. Optimal population and individual strategies for prophylaxis and treatment might

Targeted nanosystems: Advances in targeted dendrimers for cancer therapy.

PubMed

Yang, Hu

2016-02-01

Dendrimers possess discrete highly compact nanostructures constituted of successive branched layers. Soon after the inception of dendrimers, recognition of their tunable structures and biologically favorable properties provoked a great enthusiasm in delving deeply into the utility of dendrimers for biomedical and pharmaceutical applications. One of the most important nanotechnology applications is the development of nanomedicines for targeted cancer therapies. Tremendous success in targeted therapies has been achieved with the use of dendrimer-based nanomedicines. This article provides a concise review on latest advances in the utility of dendrimers in immunotherapies and hormone therapies. Much basic and clinical research has been done since the invention of dendrimers, which are highly branched nano-sized molecules with the ability to act as carriers in nanomedicine. In this concise review article, the authors highlighted the current use of dendrimers in immunotherapies and hormone therapies in the fight against cancers. Copyright © 2015 Elsevier Inc. All rights reserved.

Antiviral Effects of Saffron and its Major Ingredients.

PubMed

Soleymani, Sepehr; Zabihollahi, Rezvan; Shahbazi, Sepideh; Bolhassani, Azam

2018-01-01

The lack of an effective vaccine against viral infections, toxicity of the synthetic anti-viral drugs and the generation of resistant viral strains led to discover novel inhibitors. Recently, saffron and its compounds were used to treat different pathological conditions. In this study, we tested the anti-HSV-1 and anti-HIV-1 activities of Iranian saffron extract and its major ingredients including crocin and picrocrocin as well as cytotoxicity in vitro. The data showed that the aqueous saffron extract was not active against HIV-1 and HSV-1 virions at certain doses (i.e., a mild activity), but crocin and picrocrocin indicated significant anti-HSV-1 and also anti-HIV-1 activities. Crocin inhibited the HSV replication at before and after entry of virions into Vero cells. Indeed, crocin carotenoid suppressed HSV penetration in the target cells as well as disturbed virus replication after entry into the cells. Picrocrocin was also effective for inhibiting virus entry and also its replication. This monoterpen aldehyde showed higher anti-HSV effects after virus penetrating in the cells. Generally, these sugar-containing compounds extracted from saffron showed to be effective antiherpetic drug candidates. The recent study is the first report suggesting antiviral activities for saffron extract and its major ingredients. Crocin and picrocrocin could be a promising anti-HSV and anti-HIV agent for herbal therapy against viral infections. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Short interfering RNA confers intracellular antiviral immunity in human cells.

PubMed

Gitlin, Leonid; Karelsky, Sveta; Andino, Raul

2002-07-25

Gene silencing mediated by double-stranded RNA (dsRNA) is a sequence-specific, highly conserved mechanism in eukaryotes. In plants, it serves as an antiviral defence mechanism. Animal cells also possess this machinery but its specific function is unclear. Here we demonstrate that dsRNA can effectively protect human cells against infection by a rapidly replicating and highly cytolytic RNA virus. Pre-treatment of human and mouse cells with double-stranded, short interfering RNAs (siRNAs) to the poliovirus genome markedly reduces the titre of virus progeny and promotes clearance of the virus from most of the infected cells. The antiviral effect is sequence-specific and is not attributable to either classical antisense mechanisms or to interferon and the interferon response effectors protein kinase R (PKR) and RNaseL. Protection is the result of direct targeting of the viral genome by siRNA, as sequence analysis of escape virus (resistant to siRNAs) reveals one nucleotide substitution in the middle of the targeted sequence. Thus, siRNAs elicit specific intracellular antiviral resistance that may provide a therapeutic strategy against human viruses.

Antiviral activity of recombinant ankyrin targeted to the capsid domain of HIV-1 Gag polyprotein

PubMed Central

2012-01-01

Background Ankyrins are cellular mediators of a number of essential protein-protein interactions. Unlike intrabodies, ankyrins are composed of highly structured repeat modules characterized by disulfide bridge-independent folding. Artificial ankyrin molecules, designed to target viral components, might act as intracellular antiviral agents and contribute to the cellular immunity against viral pathogens such as HIV-1. Results A phage-displayed library of artificial ankyrins was constructed, and screened on a polyprotein made of the fused matrix and capsid domains (MA-CA) of the HIV-1 Gag precursor. An ankyrin with three modules named AnkGAG1D4 (16.5 kDa) was isolated. AnkGAG1D4 and MA-CA formed a protein complex with a stoichiometry of 1:1 and a dissociation constant of Kd ~ 1 μM, and the AnkGAG1D4 binding site was mapped to the N-terminal domain of the CA, within residues 1-110. HIV-1 production in SupT1 cells stably expressing AnkGAG1D4 in both N-myristoylated and non-N-myristoylated versions was significantly reduced compared to control cells. AnkGAG1D4 expression also reduced the production of MLV, a phylogenetically distant retrovirus. The AnkGAG1D4-mediated antiviral effect on HIV-1 was found to occur at post-integration steps, but did not involve the Gag precursor processing or cellular trafficking. Our data suggested that the lower HIV-1 progeny yields resulted from the negative interference of AnkGAG1D4-CA with the Gag assembly and budding pathway. Conclusions The resistance of AnkGAG1D4-expressing cells to HIV-1 suggested that the CA-targeted ankyrin AnkGAG1D4 could serve as a protein platform for the design of a novel class of intracellular inhibitors of HIV-1 assembly based on ankyrin-repeat modules. PMID:22348230

Gene Therapy and Targeted Toxins for Glioma

PubMed Central

Castro, Maria G.; Candolfi, Marianela; Kroeger, Kurt; King, Gwendalyn D.; Curtin, James F.; Yagiz, Kader; Mineharu, Yohei; Assi, Hikmat; Wibowo, Mia; Muhammad, AKM Ghulam; Foulad, David; Puntel, Mariana; Lowenstein, Pedro R.

2011-01-01

The most common primary brain tumor in adults is glioblastoma. These tumors are highly invasive and aggressive with a mean survival time of nine to twelve months from diagnosis to death. Current treatment modalities are unable to significantly prolong survival in patients diagnosed with glioblastoma. As such, glioma is an attractive target for developing novel therapeutic approaches utilizing gene therapy. This review will examine the available preclinical models for glioma including xenographs, syngeneic and genetic models. Several promising therapeutic targets are currently being pursued in pre-clinical investigations. These targets will be reviewed by mechanism of action, i.e., conditional cytotoxic, targeted toxins, oncolytic viruses, tumor suppressors/oncogenes, and immune stimulatory approaches. Preclinical gene therapy paradigms aim to determine which strategies will provide rapid tumor regression and long-term protection from recurrence. While a wide range of potential targets are being investigated preclinically, only the most efficacious are further transitioned into clinical trial paradigms. Clinical trials reported to date are summarized including results from conditionally cytotoxic, targeted toxins, oncolytic viruses and oncogene targeting approaches. Clinical trial results have not been as robust as preclinical models predicted; this could be due to the limitations of the GBM models employed. Once this is addressed, and we develop effective gene therapies in models that better replicate the clinical scenario, gene therapy will provide a powerful approach to treat and manage brain tumors. PMID:21453286

Targeted polymeric nanoparticles for cancer gene therapy

PubMed Central

Kim, Jayoung; Wilson, David R.; Zamboni, Camila G.; Green, Jordan J.

2015-01-01

In this article, advances in designing polymeric nanoparticles for targeted cancer gene therapy are reviewed. Characterization and evaluation of biomaterials, targeting ligands, and transcriptional elements are each discussed. Advances in biomaterials have driven improvements to nanoparticle stability and tissue targeting, conjugation of ligands to the surface of polymeric nanoparticles enable binding to specific cancer cells, and the design of transcriptional elements has enabled selective DNA expression specific to the cancer cells. Together, these features have improved the performance of polymeric nanoparticles as targeted non-viral gene delivery vectors to treat cancer. As polymeric nanoparticles can be designed to be biodegradable, non-toxic, and to have reduced immunogenicity and tumorigenicity compared to viral platforms, they have significant potential for clinical use. Results of polymeric gene therapy in clinical trials and future directions for the engineering of nanoparticle systems for targeted cancer gene therapy are also presented. PMID:26061296

Utilisation of hepatocellular carcinoma screening in Australians at risk of hepatitis B virus-related carcinoma and prescribed anti-viral therapy.

PubMed

Sheppard-Law, Suzanne; Zablotska-Manos, Iryna; Kermeen, Melissa; Holdaway, Susan; Lee, Alice; George, Jacob; Zekry, Amany; Maher, Lisa

2018-07-01

To investigate hepatocellular carcinoma screening utilisation and factors associated with utilisation among patients prescribed hepatitis B virus anti-viral therapy and at risk of hepatocellular carcinoma. The incidence of hepatocellular carcinoma has increased in Australia over the past three decades with chronic hepatitis B virus infection a major contributor. hepatocellular carcinoma surveillance programs aim to detect cancers early enabling curative treatment options, longer survival and longer times to recurrence. Multi-site cross-sectional survey. An online study questionnaire was administered to eligible participants attending three Sydney tertiary hospitals. Data were grouped into six mutually exclusive hepatocellular carcinoma risk factor categories as per American Association for the Study of Liver Diseases guidelines. All analyses were undertaken in STATA. Logistic regression was used to assess the associations between covariates and screening utilisation. Multivariate models described were assessed using the Hosmer-Lemeshow goodness of fit. Of the 177 participants, 137 (77.4%) self-reported that US had been performed in the last six months. Awareness that screening should be performed and knowing the correct frequency of US screening were independently associated with screening utilisation. Participants who knew that screening should be undertaken were three times more likely to have had pretreatment education or were prescribed hepatitis B virus anti-viral treatment for >4 years. Participants reporting a family history of hepatocellular carcinoma were less likely to know that screening should be undertaken every 6 months. While utilisation of hepatocellular carcinoma surveillance programs was higher in this study than in previous reports, strategies to further improve surveillance remain necessary. Findings from this research form the basis for proposing strategies to improve utilisation of hepatocellular carcinoma screening, inform hepatitis B virus

Selective enhancement of radiation response of herpes simplex virus thymidine kinase transduced 9L gliosarcoma cells in vitro and in vivo by antiviral agents

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kim, Jae Ho; Kim, Sang Hie; Kolozsvary, A.

1995-11-01

The purpose of this investigation was to demonstrate in a well-characterized tumor model that the radiosensitivity of tumor cells transduced with a herpes simplex virus thymidine kinase gene (HS-tk) would be selectively enhanced by antiviral agents. Rat 9L gliosarcoma cells transduced with a retroviral vector containing an HS-tk gene, 9L-tk cells were exposed to various doses or irradiation under either in vitro or in vivo conditions. The radiation sensitizing potential of two antiviral drugs, bromovinyl deoxyuridine (BVdU) and dihydroxymethyl ethyl methyl guanine (acyclovir), was evaluated in vitro. The radiosensitizing ability of BVdU was also evaluated with a 9L-tk tumor growingmore » in the rat brain. Tumors growing in the right hemisphere of rat brains were irradiated stereotactically with single-dose irradiation. The radiation response of 9L-tk cells was selectively enhanced by antiviral agents relative to nontransduced cells. In the cell culture, when a 24-h drug exposure (20 {mu}g/ml) preceded radiation, the sensitizer enhancement ratio (SER) for BVdU and acyclovir was 1.4 {plus_minus} 0.1 and 1.3 {plus_minus} 0.1, respectively. Exposure of cells to 10 {mu}g/ml acyclovir for two 24-h periods both pre- and postirradiation resulted in a SER of 1.6 {plus_minus} 0.1. In vivo, a significant increase in median survival time of rats with 9L-tk tumors was found when BVdU was administered prior to single-dose irradiation relative to the survival time of similar rats receiving radiation alone. An antiviral agent can enhance cell killing by radiation with selective action in cells transduced with the herpes simplex virus thymidine kinase gene. The results suggest that the three-pronged therapy of HS-tk gene transduction, systemically administered antiviral drug, and stereotactically targeted radiation therapy will improve the effectiveness of radiation therapy for the treatment of radioresistant tumors. 25 refs., 6 figs.« less

Heart failure—potential new targets for therapy

PubMed Central

Nabeebaccus, Adam; Zheng, Sean; Shah, Ajay M.

2016-01-01

Abstract Introduction/background Heart failure is a major cause of cardiovascular morbidity and mortality. This review covers current heart failure treatment guidelines, emerging therapies that are undergoing clinical trial, and potential new therapeutic targets arising from basic science advances. Sources of data A non-systematic search of MEDLINE was carried out. International guidelines and relevant reviews were searched for additional articles. Areas of agreement Angiotensin-converting enzyme inhibitors and beta-blockers are first line treatments for chronic heart failure with reduced left ventricular function. Areas of controversy Treatment strategies to improve mortality in heart failure with preserved left ventricular function are unclear. Growing points Many novel therapies are being tested for clinical efficacy in heart failure, including those that target natriuretic peptides and myosin activators. A large number of completely novel targets are also emerging from laboratory-based research. Better understanding of pathophysiological mechanisms driving heart failure in different settings (e.g. hypertension, post-myocardial infarction, metabolic dysfunction) may allow for targeted therapies. Areas timely for developing research Therapeutic targets directed towards modifying the extracellular environment, angiogenesis, cell viability, contractile function and microRNA-based therapies. PMID:27365454

Imaging analysis of nuclear antiviral factors through direct detection of incoming adenovirus genome complexes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Komatsu, Tetsuro; Department of Infection Biology, Faculty of Medicine, University of Tsukuba, Tsukuba 305-8575; Will, Hans

2016-04-22

Recent studies involving several viral systems have highlighted the importance of cellular intrinsic defense mechanisms through nuclear antiviral proteins that restrict viral propagation. These factors include among others components of PML nuclear bodies, the nuclear DNA sensor IFI16, and a potential restriction factor PHF13/SPOC1. For several nuclear replicating DNA viruses, it was shown that these factors sense and target viral genomes immediately upon nuclear import. In contrast to the anticipated view, we recently found that incoming adenoviral genomes are not targeted by PML nuclear bodies. Here we further explored cellular responses against adenoviral infection by focusing on specific conditions asmore » well as additional nuclear antiviral factors. In line with our previous findings, we show that neither interferon treatment nor the use of specific isoforms of PML nuclear body components results in co-localization between incoming adenoviral genomes and the subnuclear domains. Furthermore, our imaging analyses indicated that neither IFI16 nor PHF13/SPOC1 are likely to target incoming adenoviral genomes. Thus our findings suggest that incoming adenoviral genomes may be able to escape from a large repertoire of nuclear antiviral mechanisms, providing a rationale for the efficient initiation of lytic replication cycle. - Highlights: • Host nuclear antiviral factors were analyzed upon adenovirus genome delivery. • Interferon treatments fail to permit PML nuclear bodies to target adenoviral genomes. • Neither Sp100A nor B targets adenoviral genomes despite potentially opposite roles. • The nuclear DNA sensor IFI16 does not target incoming adenoviral genomes. • PHF13/SPOC1 targets neither incoming adenoviral genomes nor genome-bound protein VII.« less

Ribonuclease from Bacillus Acts as an Antiviral Agent against Negative- and Positive-Sense Single Stranded Human Respiratory RNA Viruses

PubMed Central

Müller, Christin; Romanova, Yulia; Mostafa, Ahmed; Ulyanova, Vera; Pleschka, Stephan; Ilinskaya, Olga

2017-01-01

Bacillus pumilus ribonuclease (binase) was shown to be a promising antiviral agent in animal models and cell cultures. However, the mode of its antiviral action remains unknown. To assess the binase effect on intracellular viral RNA we have selected single stranded negative- and positive-sense RNA viruses, influenza virus, and rhinovirus, respectively, which annually cause respiratory illnesses and are characterized by high contagious nature, mutation rate, and antigen variability. We have shown that binase exerts an antiviral effect on both viruses at the same concentration, which does not alter the spectrum of A549 cellular proteins and expression of housekeeping genes. The titers of influenza A (H1N1pdm) virus and human rhinovirus serotype 1A were reduced by 40% and 65%, respectively. A preincubation of influenza virus with binase before infection significantly reduced viral titer after single-cycle replication of the virus. Using influenza A virus mini genome system we showed that binase reduced GFP reporter signaling indicating a binase action on the expression of viral mRNA. Binase reduced the level of H1N1pdm viral NP mRNA accumulation in A549 cells by 20%. Since the viral mRNA is a possible target for binase this agent could be potentially applied in the antiviral therapy against both negative- and positive-sense RNA viruses. PMID:28546965

Targeted Therapy for Melanoma

DOE Office of Scientific and Technical Information (OSTI.GOV)

Quinn, Thomas; Moore, Herbert

The research project, entitled ”Targeted Therapy for Melanoma,” was focused on investigating the use of kidney protection measures to lower the non-specific kidney uptake of the radiolabeled Pb-DOTA-ReCCMSH peptide. Previous published work demonstrated that the kidney exhibited the highest non-target tissue uptake of the 212Pb/203Pb radiolabeled melanoma targeting peptide DOTA-ReCCMSH. The radiolabeled alpha-melanocyte stimulating hormone (α-MSH) peptide analog DOTA-Re(Arg 11)CCMSH, which binds the melanocortin-1 receptor over-expressed on melanoma tumor cells, has shown promise as a PRRT agent in pre-clinical studies. High tumor uptake of 212Pb labeled DOTA-Re(Arg 11)CCMSH resulted in tumor reduction or eradication in melanoma therapy studies. Of particularmore » note was the 20-50% cure rate observed when melanoma mice were treated with alpha particle emitter 212Pb. However, as with most PRRT agents, high radiation doses to the kidneys where observed. To optimize tumor treatment efficacy and reduce nephrotoxicity, the tumor to kidney uptake ratio must be improved. Strategies to reduce kidney retention of the radiolabeled peptide, while not effecting tumor uptake and retention, can be broken into several categories including modification of the targeting peptide sequence and reducing proximal tubule reabsorption.« less

The mitochondrial targeting chaperone 14-3-3ε regulates a RIG-I translocon that mediates membrane-association and innate antiviral immunity

PubMed Central

Liu, Helene Minyi; Loo, Yueh-Ming; Horner, Stacy M.; Zornetzer, Gregory A.; Katze, Michael G.; Gale, Michael

2012-01-01

Summary RIG-I is a cytosolic pathogen recognition receptor that initiates immune responses against RNA viruses. Upon viral RNA recognition, anti-viral signalling requires RIG-I redistribution from the cytosol to membranes where it binds the adaptor protein, MAVS. Here we identify the mitochondrial targeting chaperone protein, 14-3-3ε, as a RIG-I-binding partner and essential component of a translocation complex or “translocon” containing RIG-I, 14-3-3ε, and the TRIM25 ubiquitin ligase. The RIG-I translocon directs RIG-I redistribution from the cytosol to membranes where it mediates MAVS-dependent innate immune signalling during acute RNA virus infection. 14-3-3ε is essential for the stable interaction of RIG-I with TRIM25, which facilitates RIG-I ubiquitination and initiation of innate immunity against hepatitis C virus and other pathogenic RNA viruses. Our results define 14-3-3ε as a key component of a RIG-I translocon required for innate antiviral immunity. PMID:22607805

The mitochondrial targeting chaperone 14-3-3ε regulates a RIG-I translocon that mediates membrane association and innate antiviral immunity.

PubMed

Liu, Helene Minyi; Loo, Yueh-Ming; Horner, Stacy M; Zornetzer, Gregory A; Katze, Michael G; Gale, Michael

2012-05-17

RIG-I is a cytosolic pathogen recognition receptor that initiates immune responses against RNA viruses. Upon viral RNA recognition, antiviral signaling requires RIG-I redistribution from the cytosol to membranes where it binds the adaptor protein, MAVS. Here we identify the mitochondrial targeting chaperone protein, 14-3-3ε, as a RIG-I-binding partner and essential component of a translocation complex or "translocon" containing RIG-I, 14-3-3ε, and the TRIM25 ubiquitin ligase. The RIG-I translocon directs RIG-I redistribution from the cytosol to membranes where it mediates MAVS-dependent innate immune signaling during acute RNA virus infection. 14-3-3ε is essential for the stable interaction of RIG-I with TRIM25, which facilitates RIG-I ubiquitination and initiation of innate immunity against hepatitis C virus and other pathogenic RNA viruses. Our results define 14-3-3ε as a key component of a RIG-I translocon required for innate antiviral immunity. Copyright © 2012 Elsevier Inc. All rights reserved.

Targeted therapies in gastric cancer and future perspectives.

PubMed

Yazici, Ozan; Sendur, M Ali Nahit; Ozdemir, Nuriye; Aksoy, Sercan

2016-01-14

Advanced gastric cancer (AGC) is associated with a high mortality rate and, despite multiple new chemotherapy options, the survival rates of patients with AGC remains poor. After the discovery of targeted therapies, research has focused on the new treatment options for AGC. In the last two decades, many targeted molecules were developed against AGC. Currently, two targeted therapy molecules have been approved for patients with AGC. In 2010, trastuzumab was the first molecule shown to improve survival in patients with HER2-positive AGC as part of a first-line combination regimen. In 2014, ramucirumab was the second targeted molecule to improve survival rates and was suggested as treatment for patients with AGC who had progressed after first-line platinum plus fluoropyrimidine with or without anthracycline chemotherapy. Ramucirumab was the first targeted therapy acting as a single agent in patients with advanced gastroesophageal cancers. Although these two molecules were introduced into clinical use, many other promising molecules have been tested in phase I-II trials. It is obvious that in the near future many different targeted therapies will be in use for treatment of AGC. In this review, the current status of targeted therapies in the treatment of AGC and gastroesophageal junction tumors, including HER (2-3) inhibitors, epidermal growth factor receptor inhibitors, tyrosine kinase inhibitors, antiangiogenic agents, c-MET inhibitors, mammalian target of rapamycin inhibitors, agents against other molecular pathways fibroblast growth factor, Claudins, insulin-like growth factor, heat shock proteins, and immunotherapy, will be discussed.

Estimated impact of aggressive empirical antiviral treatment in containing an outbreak of pandemic influenza H1N1 in an isolated First Nations community.

PubMed

Xiao, Yanyu; Patel, Zeenat; Fiddler, Adam; Yuan, Lilian; Delvin, Marie-Elaine; Fisman, David N

2013-11-01

The 2009 influenza A (H1N1) pandemic was mild by historical standards, but was more severe in isolated Canadian Indigenous communities. Oseltamivir was used aggressively for outbreak control in an isolated northern Ontario First Nations community. We used mathematical modeling to quantify the impact of antiviral therapy on the course of this outbreak. We used both a Richards growth model and a compartmental model to evaluate the characteristics of the outbreak based on both respiratory visits and influenza-like illness counts. Estimates of best-fit model parameters, including basic reproductive number (R0 ) and antiviral efficacy, and simulations, were used to estimate the impact of antiviral drugs compared to social distancing interventions alone. Using both approaches, we found that a rapidly growing outbreak slowed markedly with aggressive antiviral therapy. Richards model turning points occurred within 24 hours of antiviral implementation. Compartmental models estimated antiviral efficacy at 70-95%. Plausible estimates of R from both modeling approaches ranged from 4·0 to 15·8, higher than published estimates for southern Canada; utilization of aggressive antiviral therapy in this community prevented 962-1757 cases of symptomatic influenza and as many as 114 medical evacuations in this community. Although not advocated in other settings in Canada, aggressive antiviral therapy markedly reduced the impact of a pandemic-related influenza A (H1N1) outbreak in an isolated Canadian First Nations community in northern Ontario, Canada. The differential risk experienced by such communities makes tailored interventions that consider risk and lack of access to medical services, appropriate. © 2013 John Wiley & Sons Ltd.

Prostate Cancer Clinical Consortium Clinical Research Site:Targeted Therapies

DTIC Science & Technology

2015-10-01

AWARD NUMBER: W81XWH-14-2-0159 TITLE: Prostate Cancer Clinical Consortium Clinical Research Site: Targeted Therapies PRINCIPAL INVESTIGATOR...Sep 2015 4. TITLE AND SUBTITLE 5a. CONTRACT NUMBER Prostate Cancer Clinical Consortium Clinical Research Site: Targeted Therapies 5b. GRANT NUMBER... therapy resistance/sensitivity, identification of new therapeutic targets through high quality genomic analyses, providing access to the highest quality

Novel Approaches for Targeting Antiviral Agents in the Treatment of Arena-, Bunya-, Flavi-, and Retroviral Infections

DTIC Science & Technology

1989-05-22

potentially useful antivirals (e... S-HMPA, selenazole, WIN 5177, arildone, phosphonoformic acid ) are currently under investigation. There are, however...by increasing dosage, this often results in toxicity. For example, a number of antiviral agents (ribavirin, adenine arabinoside, phosphonoformic acid ...Three possibilities exist for the activation of carrier bound drugs: 1) endocytosis and release in acidic endosomes; 2) extracellular activation at cell

Inhibition of CRM1-mediated nuclear export of influenza A nucleoprotein and nuclear export protein as a novel target for antiviral drug development.

PubMed

Chutiwitoonchai, Nopporn; Mano, Takafumi; Kakisaka, Michinori; Sato, Hirotaka; Kondoh, Yasumitsu; Osada, Hiroyuki; Kotani, Osamu; Yokoyama, Masaru; Sato, Hironori; Aida, Yoko

2017-07-01

An anti-influenza compound, DP2392-E10 based on inhibition of the nuclear export function of the viral nucleoprotein-nuclear export signal 3 (NP-NES3) domain was successfully identified by our previous high-throughput screening system. Here, we demonstrated that DP2392-E10 exerts its antiviral effect by inhibiting replication of a broad range of influenza A subtypes. In regard to the molecular mechanism, we revealed that DP2392-E10 inhibits nuclear export of both viral NP and nuclear export protein (NEP). More specifically, in vitro pull-down assays revealed that DP2392-E10 directly binds cellular CRM1, which mediates nuclear export of NP and NEP. In silico docking suggested that DP2392-E10 binds at a region close to the HEAT9 and HEAT10 domains of CRM1. Together, these results indicate that the CRM1-mediated nuclear export function of influenza virus represents a new potential target for antiviral drug development, and also provide a core structure for a novel class of inhibitors that target this function. Copyright © 2017 Elsevier Inc. All rights reserved.

Significant renoprotective effect of telbivudine during preemptive antiviral therapy in advanced liver cancer patients receiving cisplatin-based chemotherapy: a case-control study.

PubMed

Lin, Chih-Lang; Chien, Rong-Nan; Yeh, Charisse; Hsu, Chao-Wei; Chang, Ming-Ling; Chen, Yi-Cheng; Yeh, Chau-Ting

2014-12-01

Cisplatin is a known nephrotoxic agent requiring vigorous hydration before use. However, aggressive hydration could be life-threatening. Therefore, in cirrhotic patients with advanced hepatocellular carcinoma (HCC) under cisplatin-based chemotherapy, the risk of nephrotoxicity increased. Because previous studies showed that long-term telbivudine treatment improved renal function in chronic hepatitis B virus (HBV) infected patients, we conducted a case-control study to evaluate the clinical outcome of telbivudine preemptive therapy in HBV-related advanced HCC patients treated by combination chemotherapy comprising 5-fluorouracil, mitoxantrone and cisplatin (FMP). From June 2007 to March 2012, 60 patients with HBV-related advanced HCC, all receiving the same FMP chemotherapy protocol, were enrolled. Of them, 20 did not receive any antiviral therapy, whereas the remaining 40 patients (sex and age matched) received telbivudine preemptive therapy. Progressive decrease of aminotransferase levels (p < 0.05) and progressive increase of viral clearance rates (p < 0.001) were found in telbivudine-treated group. No drug resistance developed during the course of treatment. When compared with non-antiviral-treated patients, a significantly higher post-therapeutic estimated glomerular filtration rate (eGFR) was found in the telbivudine-treated group (p < 0.001). In patients with initial eGFR >100 ml/min (n = 34), the median overall survival was significantly longer in the telbivudine-treated group (12.1 vs. 4.9 months; p = 0.042). Preemptive use of telbivudine significantly prevented eGFR deterioration caused by cisplatin-based chemotherapy in HBV-related advanced HCC. In patients with initially sufficient eGFR level, telbivudine treatment was associated with a longer overall survival.

Will nanotechnology influence targeted cancer therapy?

PubMed Central

Grimm, Jan; Scheinberg, David A.

2011-01-01

The rapid development of techniques that enable synthesis (and manipulation) of matter on the nanometer scale, as well as the development of new nano-materials, will play a large role in disease diagnosis and treatment, specifically in targeted cancer therapy. Targeted nanocarriers are an intriguing means to selectively deliver high concentrations of cytotoxic agents or imaging labels directly to the cancer site. Often solubility issues and an unfavorable biodistribution can result in a suboptimal response of novel agents even though they are very potent. New nanoparticulate formulations allow simultaneous imaging and therapy (“theranostics”), which can provide a realistic means for the clinical implementation of such otherwise suboptimal formulations. In this review we will not attempt to provide a complete overview of the rapidly enlarging field of nanotechnology in cancer; rather, we will present properties specific to nanoparticles, and examples of their uses, which demonstrate their importance for targeted cancer therapy. PMID:21356476

ESCMID Study Group for Infections in Compromised Hosts (ESGICH) Consensus Document on the safety of targeted and biological therapies: an infectious diseases perspective (Soluble immune effector molecules [I]: anti-tumor necrosis factor-α agents).

PubMed

Baddley, J W; Cantini, F; Goletti, D; Gómez-Reino, J J; Mylonakis, E; San-Juan, R; Fernández-Ruiz, M; Torre-Cisneros, J

2018-06-01

The present review is part of the ESCMID Study Group for Infections in Compromised Hosts (ESGICH) Consensus Document on the safety of targeted and biological therapies. To review, from an Infectious Diseases perspective, the safety profile of agents targeting tumour necrosis factor-α (TNF-α) and to suggest preventive recommendations. Computer-based MEDLINE searches with MeSH terms pertaining to each agent or therapeutic family. Preclinical and clinical evidence indicate that anti-TNF-α therapy (infliximab, adalimumab, golimumab, certolizumab pegol and etanercept) is associated with a two-to four-fold increase in the risk of active tuberculosis and other granulomatous conditions (mostly resulting from the reactivation of a latent infection). In addition, it may lead to the occurrence of other serious infections (bacterial, fungal, opportunistic and certain viral infections). These associated risks seem to be lower for etanercept than other agents. Screening for latent tuberculosis infection should be performed before starting anti-TNF-α therapy, followed by anti-tuberculosis therapy if appropriate. Screening for chronic hepatitis B virus (HBV) infection is also recommended, and antiviral prophylaxis may be warranted for hepatitis B surface antigen-positive individuals. No benefit is expected from the use of antibacterial, anti-Pneumocystis or antifungal prophylaxis. Pneumococcal and age-appropriate antiviral vaccinations (i.e. influenza) should be administered. Live-virus vaccines (i.e. varicella-zoster virus or measles-mumps-rubella) may be contraindicated in people receiving anti-TNF-α therapy, although additional data are needed before definitive recommendations can be made. Prevention measures should be implemented to reduce the risk of latent tuberculosis or HBV reactivation among individuals receiving anti-TNF-α therapy. Copyright © 2018 European Society of Clinical Microbiology and Infectious Diseases. Published by Elsevier Ltd. All rights reserved.

Development of Potent Antiviral Drugs Inspired by Viral Hexameric DNA-Packaging Motors with Revolving Mechanism

PubMed Central

Pi, Fengmei; Zhao, Zhengyi; Chelikani, Venkata; Yoder, Kristine; Kvaratskhelia, Mamuka

2016-01-01

The intracellular parasitic nature of viruses and the emergence of antiviral drug resistance necessitate the development of new potent antiviral drugs. Recently, a method for developing potent inhibitory drugs by targeting biological machines with high stoichiometry and a sequential-action mechanism was described. Inspired by this finding, we reviewed the development of antiviral drugs targeting viral DNA-packaging motors. Inhibiting multisubunit targets with sequential actions resembles breaking one bulb in a series of Christmas lights, which turns off the entire string. Indeed, studies on viral DNA packaging might lead to the development of new antiviral drugs. Recent elucidation of the mechanism of the viral double-stranded DNA (dsDNA)-packaging motor with sequential one-way revolving motion will promote the development of potent antiviral drugs with high specificity and efficiency. Traditionally, biomotors have been classified into two categories: linear and rotation motors. Recently discovered was a third type of biomotor, including the viral DNA-packaging motor, beside the bacterial DNA translocases, that uses a revolving mechanism without rotation. By analogy, rotation resembles the Earth's rotation on its own axis, while revolving resembles the Earth's revolving around the Sun (see animations at http://rnanano.osu.edu/movie.html). Herein, we review the structures of viral dsDNA-packaging motors, the stoichiometries of motor components, and the motion mechanisms of the motors. All viral dsDNA-packaging motors, including those of dsDNA/dsRNA bacteriophages, adenoviruses, poxviruses, herpesviruses, mimiviruses, megaviruses, pandoraviruses, and pithoviruses, contain a high-stoichiometry machine composed of multiple components that work cooperatively and sequentially. Thus, it is an ideal target for potent drug development based on the power function of the stoichiometries of target complexes that work sequentially. PMID:27356896

Cytotoxic, Virucidal, and Antiviral Activity of South American Plant and Algae Extracts

PubMed Central

Faral-Tello, Paula; Mirazo, Santiago; Dutra, Carmelo; Pérez, Andrés; Geis-Asteggiante, Lucía; Frabasile, Sandra; Koncke, Elina; Davyt, Danilo; Cavallaro, Lucía; Heinzen, Horacio; Arbiza, Juan

2012-01-01

Herpes simplex virus type 1 (HSV-1) infection has a prevalence of 70% in the human population. Treatment is based on acyclovir, valacyclovir, and foscarnet, three drugs that share the same mechanism of action and of which resistant strains have been isolated from patients. In this aspect, innovative drug therapies are required. Natural products offer unlimited opportunities for the discovery of antiviral compounds. In this study, 28 extracts corresponding to 24 plant species and 4 alga species were assayed in vitro to detect antiviral activity against HSV-1. Six of the methanolic extracts inactivated viral particles by direct interaction and 14 presented antiviral activity when incubated with cells already infected. Most interesting antiviral activity values obtained are those of Limonium brasiliense, Psidium guajava, and Phyllanthus niruri, which inhibit HSV-1 replication in vitro with 50% effective concentration (EC50) values of 185, 118, and 60 μg/mL, respectively. For these extracts toxicity values were calculated and therefore selectivity indexes (SI) obtained. Further characterization of the bioactive components of antiviral plants will pave the way for the discovery of new compounds against HSV-1. PMID:22619617

Understanding the hepatitis C virus life cycle paves the way for highly effective therapies

PubMed Central

Scheel, Troels K H; Rice, Charles M

2014-01-01

More than two decades of intense research has provided a detailed understanding of hepatitis C virus (HCV), which chronically infects 2% of the world's population. This effort has paved the way for the development of antiviral compounds to spare patients from life-threatening liver disease. An exciting new era in HCV therapy dawned with the recent approval of two viral protease inhibitors, used in combination with pegylated interferon-α and ribavirin; however, this is just the beginning. Multiple classes of antivirals with distinct targets promise highly efficient combinations, and interferon-free regimens with short treatment duration and fewer side effects are the future of HCV therapy. Ongoing and future trials will determine the best antiviral combinations and whether the current seemingly rich pipeline is sufficient for successful treatment of all patients in the face of major challenges, such as HCV diversity, viral resistance, the influence of host genetics, advanced liver disease and other co-morbidities. PMID:23836234

HIV enhancing activity of semen impairs the antiviral efficacy of microbicides

PubMed Central

Zirafi, Onofrio; Kim, Kyeong-Ae; Roan, Nadia R.; Kluge, Silvia F.; Müller, Janis A.; Jiang, Shibo; Mayer, Benjamin; Greene, Warner C.; Kirchhoff, Frank; Münch, Jan

2015-01-01

Topically applied microbicides potently inhibit HIV in vitro but have largely failed to exert protective effects in clinical trials. One possible reason for this discrepancy is that the preclinical testing of microbicides does not faithfully reflect the conditions of HIV sexual transmission. Here, we report that candidate microbicides that target HIV components show greatly reduced antiviral efficacy in the presence of semen, the main vector for HIV transmission. This diminished antiviral activity was dependent on the ability of amyloid fibrils in semen to enhance the infectivity of HIV. Thus, the anti-HIV efficacy of microbicides determined in the absence of semen greatly underestimated the drug concentrations needed to block semen-exposed virus. One notable exception was Maraviroc. This HIV entry inhibitor targets the host cell CCR5 coreceptor and was highly active against both untreated and semen-exposed HIV. These data help explain why microbicides have failed to protect against HIV in clinical trials and suggest that antiviral compounds targeting host factors hold promise for further development. These findings also suggest that the in vitro efficacy of candidate microbicides should be determined in the presence of semen to identify the best candidates for the prevention of HIV sexual transmission. PMID:25391483

Issues and controversies of hepatocellular carcinoma-targeted therapy clinical trials in Asia: experts' opinion.

PubMed

Chen, Pei-Jer; Furuse, Junji; Han, Kwang-Hyub; Hsu, Chiun; Lim, Ho-Yeong; Moon, Hanlim; Qin, Shukui; Ye, Sheng-Long; Yeoh, Ee-Min; Yeo, Winnie

2010-11-01

Asia has a disproportionate share of the world's burden of hepatocellular carcinoma (HCC). However, the highly regarded clinical practice guidelines and recommendations for the design and conduct of clinical trials for HCC largely reflect Western practice. In order to design mutually beneficial international clinical trials of promising targeted therapies, it is imperative to understand how the aetiology, staging and treatment of HCC differ between Asian and Western countries. Our group, comprising experts in oncology and hepatology from countries that constitute the Eastern Asian region, convened to compare and contrast our current practices, evaluate potential compliance with the clinical trial recommendations, and offer suggestions for modifications that would enhance international collaboration. Here, we describe the results of our discussions, including recommendations for appropriate patient stratification based on potentially important differences in HCC aetiology, identification of practices that may confound interpretation of clinical trial outcomes (traditional Chinese medicine; antivirals that target hepatitis B virus; heterogeneous embolization procedures), suggestions for utilizing a common staging system in study protocols, recognition that sorafenib usage is limited by financial constraints and potentially increased toxicity in Asian patients, and expansion of patient populations that should be eligible for initial clinical trials with new agents. © 2010 John Wiley & Sons A/S.

A new class of dual-targeted antivirals: monophosphorylated acyclovir prodrug derivatives suppress both human immunodeficiency virus type 1 and herpes simplex virus type 2.

PubMed

Vanpouille, Christophe; Lisco, Andrea; Derudas, Marco; Saba, Elisa; Grivel, Jean-Charles; Brichacek, Beda; Scrimieri, Francesca; Schinazi, Raymond; Schols, Dominique; McGuigan, Christopher; Balzarini, Jan; Margolis, Leonid

2010-02-15

Human immunodeficiency virus type 1 (HIV-1) and herpes simplex virus type 2 (HSV-2) are responsible for 2 intersecting epidemics in which the disease caused by 1 virus facilitates the transmission of and pathogenesis by the other. Therefore, suppression of one virus infection will affect the other. Acyclovir, a common antiherpetic drug, was shown to directly suppress both viruses in coinfected tissues. However, both antiviral activities of acyclovir are dependent on phosphorylation by the nucleoside kinase activity of coinfecting human herpesviruses. We developed acyclovir ProTides, monophosphorylated acyclovir with the phosphate group masked by lipophilic groups to allow efficient cellular uptake, and investigated their antiviral potential in cell lines and in human tissues ex vivo. Acyclovir ProTides suppressed both HIV-1 and HSV-2 at median effective concentrations in the submicromolar range in ex vivo lymphoid and cervicovaginal human tissues and at 3-12 micromol/L in CD4(+) T cells. Acyclovir ProTides retained activity against acyclovir-resistant HSV-2. Acyclovir ProTides represent a new class of antivirals that suppress both HIV-1 and HSV-2 by directly and independently blocking the key replicative enzymes of both viruses. Further optimization of such compounds may lead to double-targeted antivirals that can prevent viral transmission and treat the 2 synergistic diseases caused by HIV-1 and HSV-2. To our knowledge, the acyclovir ProTides described here represent the first example of acyclic nucleoside monophosphate prodrugs being active against HIV-1.

Boron neutron capture therapy: Moving toward targeted cancer therapy.

PubMed

Mirzaei, Hamid Reza; Sahebkar, Amirhossein; Salehi, Rasoul; Nahand, Javid Sadri; Karimi, Ehsan; Jaafari, Mahmoud Reza; Mirzaei, Hamed

2016-01-01

Boron neutron capture therapy (BNCT) occurs when a stable isotope, boton-10, is irradiated with low-energy thermal neutrons to yield stripped down helium-4 nuclei and lithium-7 nuclei. It is a binary therapy in the treatment of cancer in which a cytotoxic event is triggered when an atom placed in a cancer cell. Here, we provide an overview on the application of BNCT in cancer therapy as well as current preclinical and clinical evidence on the efficacy of BNCT in the treatment of melanoma, brain tumors, head and neck cancer, and thyroid cancer. Several studies have shown that BNCT is effective in patients who had been treated with a full dose of conventional radiotherapy, because of its selectivity. In addition, BNCT is dependent on the normal/tumor tissue ratio of boron distribution. Increasing evidence has shown that BNCT can be combined with different drug delivery systems to enhance the delivery of boron to cancer cells. The flexibility of BNCT to be used in combination with different tumor-targeting approaches has made this strategy a promising option for cancer therapy. This review aims to provide a state-of-the-art overview of the recent advances in the use of BNCT for targeted therapy of cancer.

The SARS-coronavirus papain-like protease: structure, function and inhibition by designed antiviral compounds.

PubMed

Báez-Santos, Yahira M; St John, Sarah E; Mesecar, Andrew D

2015-03-01

Over 10 years have passed since the deadly human coronavirus that causes severe acute respiratory syndrome (SARS-CoV) emerged from the Guangdong Province of China. Despite the fact that the SARS-CoV pandemic infected over 8500 individuals, claimed over 800 lives and cost billions of dollars in economic loss worldwide, there still are no clinically approved antiviral drugs, vaccines or monoclonal antibody therapies to treat SARS-CoV infections. The recent emergence of the deadly human coronavirus that causes Middle East respiratory syndrome (MERS-CoV) is a sobering reminder that new and deadly coronaviruses can emerge at any time with the potential to become pandemics. Therefore, the continued development of therapeutic and prophylactic countermeasures to potentially deadly coronaviruses is warranted. The coronaviral proteases, papain-like protease (PLpro) and 3C-like protease (3CLpro), are attractive antiviral drug targets because they are essential for coronaviral replication. Although the primary function of PLpro and 3CLpro are to process the viral polyprotein in a coordinated manner, PLpro has the additional function of stripping ubiquitin and ISG15 from host-cell proteins to aid coronaviruses in their evasion of the host innate immune responses. Therefore, targeting PLpro with antiviral drugs may have an advantage in not only inhibiting viral replication but also inhibiting the dysregulation of signaling cascades in infected cells that may lead to cell death in surrounding, uninfected cells. This review provides an up-to-date discussion on the SARS-CoV papain-like protease including a brief overview of the SARS-CoV genome and replication followed by a more in-depth discussion on the structure and catalytic mechanism of SARS-CoV PLpro, the multiple cellular functions of SARS-CoV PLpro, the inhibition of SARS-CoV PLpro by small molecule inhibitors, and the prospect of inhibiting papain-like protease from other coronaviruses. This paper forms part of a series of

Harnessing the Prokaryotic Adaptive Immune System as a Eukaryotic Antiviral Defense

PubMed Central

Price, Aryn A.; Grakoui, Arash; Weiss, David S.

2016-01-01

Clustered, regularly interspaced, short palindromic repeats - CRISPR associated (CRISPR-Cas) systems are sequence specific RNA-directed endonuclease complexes that bind and cleave nucleic acids. These systems evolved within prokaryotes as adaptive immune defenses to target and degrade nucleic acids derived from bacteriophages and other foreign genetic elements. The antiviral function of these systems has now been exploited to combat eukaryotic viruses throughout the viral life cycle. Here we discuss current advances in CRISPR-Cas9 technology as a eukaryotic antiviral defense. PMID:26852268

Reduced-dose telaprevir-based triple antiviral therapy for recurrent hepatitis C after living donor liver transplantation.

PubMed

Ikegami, Toru; Yoshizumi, Tomoharu; Kato, Masaki; Yamamoto, Satomi; Fukuhara, Takasuke; Matsuura, Yoshiharu; Nakamura, Shota; Itoh, Shinji; Shirabe, Ken; Maehara, Yoshihiko

2014-11-15

The feasibility of telaprevir-based triple therapy for recurrent hepatitis C after liver transplantation (LT) has not been evaluated in Asian patients. Eleven Japanese patients received reduced-dose telaprevir (1500 mg) and adjusted-dose cyclosporine after LT. Six patients were nonresponders and three were transient responders to dual therapy. Rapid viral response, early viral response, end of treatment response, and sustained viral response were achieved in 27.3%, 90.9%, 90.9%, and 81.8% of patients, respectively. One patient had viral breakthrough at week 8 with a T54A mutation in NS3. Deep sequence analysis showed that the T54A mutation reverted to wild-type after stopping telaprevir administration. Seven patients developed severe anemia, and six received blood transfusions (4-20 U). Their hemoglobin and estimated glomerular filtration rate remained significantly lower than pretreatment values at 36 weeks after treatment. Four patients developed plasma cell hepatitis after completing telaprevir treatment, and it was treated by increasing the immunosuppressants. Although the cyclosporine level/dose ratio was 2.7 times higher at week 4 than before treatment, it was 0.7 times lower at week 36. Reduced-dosed telaprevir-based triple antiviral therapy achieved a high viral clearance rate in Japanese patients after LT. Major adverse events included severe anemia, renal dysfunction, and plasma cell hepatitis.

Oligonucleotide Aptamers: New Tools for Targeted Cancer Therapy

PubMed Central

Sun, Hongguang; Zhu, Xun; Lu, Patrick Y; Rosato, Roberto R; Tan, Wen; Zu, Youli

2014-01-01

Aptamers are a class of small nucleic acid ligands that are composed of RNA or single-stranded DNA oligonucleotides and have high specificity and affinity for their targets. Similar to antibodies, aptamers interact with their targets by recognizing a specific three-dimensional structure and are thus termed “chemical antibodies.” In contrast to protein antibodies, aptamers offer unique chemical and biological characteristics based on their oligonucleotide properties. Hence, they are more suitable for the development of novel clinical applications. Aptamer technology has been widely investigated in various biomedical fields for biomarker discovery, in vitro diagnosis, in vivo imaging, and targeted therapy. This review will discuss the potential applications of aptamer technology as a new tool for targeted cancer therapy with emphasis on the development of aptamers that are able to specifically target cell surface biomarkers. Additionally, we will describe several approaches for the use of aptamers in targeted therapeutics, including aptamer-drug conjugation, aptamer-nanoparticle conjugation, aptamer-mediated targeted gene therapy, aptamer-mediated immunotherapy, and aptamer-mediated biotherapy. PMID:25093706

Apatinib as targeted therapy for sarcoma

PubMed Central

Li, Feng; Liao, Zhichao; Zhang, Chao; Zhao, Jun; Xing, Ruwei; Teng, Sheng; Zhang, Jin; Yang, Yun; Yang, Jilong

2018-01-01

Sarcomas are a group of malignant tumors originating from mesenchymal tissue with a variety of cell subtypes. Despite several major treatment breakthroughs, standard treatment using surgery, radiation, and chemotherapy has failed to improve overall survival. Therefore, there is an urgent need to explore new strategies and innovative therapies to further improve the survival rates of patients with sarcomas. Pathological angiogenesis has an important role in the growth and metastasis of tumors. Vascular endothelial growth factor (VEGF) and vascular endothelial growth factor receptors (VEGFRs) play a central role in tumor angiogenesis and represent potential targets for anticancer therapy. As a novel targeted therapy, especially with regard to angiogenesis, apatinib is a new type of small molecule tyrosine kinase inhibitor that selectively targets VEGFR-2 and has shown encouraging anticancer activity in a wide range of malignancies, including gastric cancer, non-small cell lung cancer, breast cancer, hepatocellular carcinoma, and sarcomas. In this review, we summarize the preclinical and clinical data for apatinib, focusing primarily on its use in the treatment of sarcomas. PMID:29849960

Small molecules targeting viral RNA.

PubMed

Hermann, Thomas

2016-11-01

Highly conserved noncoding RNA (ncRNA) elements in viral genomes and transcripts offer new opportunities to expand the repertoire of drug targets for the development of antiinfective therapy. Ligands binding to ncRNA architectures are able to affect interactions, structural stability or conformational changes and thereby block processes essential for viral replication. Proof of concept for targeting functional RNA by small molecule inhibitors has been demonstrated for multiple viruses with RNA genomes. Strategies to identify antiviral compounds as inhibitors of ncRNA are increasingly emphasizing consideration of drug-like properties of candidate molecules emerging from screening and ligand design. Recent efforts of antiviral lead discovery for RNA targets have provided drug-like small molecules that inhibit viral replication and include inhibitors of human immunodeficiency virus (HIV), hepatitis C virus (HCV), severe respiratory syndrome coronavirus (SARS CoV), and influenza A virus. While target selectivity remains a challenge for the discovery of useful RNA-binding compounds, a better understanding is emerging of properties that define RNA targets amenable for inhibition by small molecule ligands. Insight from successful approaches of targeting viral ncRNA in HIV, HCV, SARS CoV, and influenza A will provide a basis for the future exploration of RNA targets for therapeutic intervention in other viral pathogens which create urgent, unmet medical needs. Viruses for which targeting ncRNA components in the genome or transcripts may be promising include insect-borne flaviviruses (Dengue, Zika, and West Nile) and filoviruses (Ebola and Marburg). WIREs RNA 2016, 7:726-743. doi: 10.1002/wrna.1373 For further resources related to this article, please visit the WIREs website. © 2016 Wiley Periodicals, Inc.

A Kinome-Wide Small Interfering RNA Screen Identifies Proviral and Antiviral Host Factors in Severe Acute Respiratory Syndrome Coronavirus Replication, Including Double-Stranded RNA-Activated Protein Kinase and Early Secretory Pathway Proteins

PubMed Central

de Wilde, Adriaan H.; Wannee, Kazimier F.; Scholte, Florine E. M.; Goeman, Jelle J.; ten Dijke, Peter; Snijder, Eric J.

2015-01-01

ABSTRACT To identify host factors relevant for severe acute respiratory syndrome-coronavirus (SARS-CoV) replication, we performed a small interfering RNA (siRNA) library screen targeting the human kinome. Protein kinases are key regulators of many cellular functions, and the systematic knockdown of their expression should provide a broad perspective on factors and pathways promoting or antagonizing coronavirus replication. In addition to 40 proteins that promote SARS-CoV replication, our study identified 90 factors exhibiting an antiviral effect. Pathway analysis grouped subsets of these factors in specific cellular processes, including the innate immune response and the metabolism of complex lipids, which appear to play a role in SARS-CoV infection. Several factors were selected for in-depth validation in follow-up experiments. In cells depleted for the β2 subunit of the coatomer protein complex (COPB2), the strongest proviral hit, we observed reduced SARS-CoV protein expression and a >2-log reduction in virus yield. Knockdown of the COPB2-related proteins COPB1 and Golgi-specific brefeldin A-resistant guanine nucleotide exchange factor 1 (GBF1) also suggested that COPI-coated vesicles and/or the early secretory pathway are important for SARS-CoV replication. Depletion of the antiviral double-stranded RNA-activated protein kinase (PKR) enhanced virus replication in the primary screen, and validation experiments confirmed increased SARS-CoV protein expression and virus production upon PKR depletion. In addition, cyclin-dependent kinase 6 (CDK6) was identified as a novel antiviral host factor in SARS-CoV replication. The inventory of pro- and antiviral host factors and pathways described here substantiates and expands our understanding of SARS-CoV replication and may contribute to the identification of novel targets for antiviral therapy. IMPORTANCE Replication of all viruses, including SARS-CoV, depends on and is influenced by cellular pathways. Although

Chemoresistance and targeted therapies in ovarian and endometrial cancers

PubMed Central

Brasseur, Kevin; Gévry, Nicolas; Asselin, Eric

2017-01-01

Gynecological cancers are known for being very aggressive at their advanced stages. Indeed, the survival rate of both ovarian and endometrial cancers is very low when diagnosed lately and the success rate of current chemotherapy regimens is not very efficient. One of the main reasons for this low success rate is the acquired chemoresistance of these cancers during their progression. The mechanisms responsible for this acquired chemoresistance are numerous, including efflux pumps, repair mechanisms, survival pathways (PI3K/AKT, MAPK, EGFR, mTOR, estrogen signaling) and tumor suppressors (P53 and Par-4). To overcome these resistances, a new type of therapy has emerged named targeted therapy. The principle of targeted therapy is simple, taking advantage of changes acquired in malignant cancer cells (receptors, proteins, mechanisms) by using compounds specifically targeting these, thus limiting their action on healthy cells. Targeted therapies are emerging and many clinical trials targeting these pathways, frequently involved in chemoresistance, have been tested on gynecological cancers. Despite some targets being less efficient than expected as mono-therapies, the combination of compounds seems to be the promising avenue. For instance, we demonstrate using ChIP-seq analysis that estrogen downregulate tumor suppressor Par-4 in hormone-dependent cells by directly binding to its DNA regulatory elements and inhibiting estrogen signaling could reinstate Par-4 apoptosis-inducing abilities. This review will focus on the chemoresistance mechanisms and the clinical trials of targeted therapies associated with these, specifically for endometrial and ovarian cancers. PMID:28008141

EGFR-targeted therapies in the post-genomic era.

PubMed

Xu, Mary Jue; Johnson, Daniel E; Grandis, Jennifer R

2017-09-01

Over 90% of head and neck cancers overexpress the epidermal growth factor receptor (EGFR). In diverse tumor types, EGFR overexpression has been associated with poorer prognosis and outcomes. Therapies targeting EGFR include monoclonal antibodies, tyrosine kinase inhibitors, phosphatidylinositol 3-kinase (PI3K) inhibitors, and antisense gene therapy. Few EGFR-targeted therapeutics are approved for clinical use. The monoclonal antibody cetuximab is a Food and Drug Administration (FDA)-approved EGFR-targeted therapy, yet has exhibited modest benefit in clinical trials. The humanized monoclonal antibody nimotuzumab is also approved for head and neck cancers in Cuba, Argentina, Colombia, Peru, India, Ukraine, Ivory Coast, and Gabon in addition to nasopharyngeal cancers in China. Few other EGFR-targeted therapeutics for head and neck cancers have led to as significant responses as seen in lung carcinomas, for instance. Recent genome sequencing of head and neck tumors has helped identify patient subgroups with improved response to EGFR inhibitors, for example, cetuximab in patients with the KRAS-variant and the tyrosine kinase inhibitor erlotinib for tumors harboring MAPK1 E322K mutations. Genome sequencing has furthermore broadened our understanding of dysregulated pathways, holding the potential to enhance the benefit derived from therapies targeting EGFR.

Prevention and management of hepatitis B virus reactivation in patients with hematological malignancies treated with anticancer therapy

PubMed Central

Law, Man Fai; Ho, Rita; Cheung, Carmen K M; Tam, Lydia H P; Ma, Karen; So, Kent C Y; Ip, Bonaventure; So, Jacqueline; Lai, Jennifer; Ng, Joyce; Tam, Tommy H C

2016-01-01

there is currently limited evidence to guide the optimal preventive measures, we recommend antiviral prophylaxis in HBsAg-positive patients receiving novel treatments, especially the Bruton tyrosine kinase inhibitors and the phosphatidylinositol 3-kinase inhibitors, which are B-cell receptor signaling modulators and reduce proliferation of malignant B-cells. Further studies are needed to clarify the risk of HBV reactivation with these agents and the best prophylactic strategy in the era of targeted therapy for hematological malignancies. PMID:27605883

Novel Targeted Therapies for Inflammatory Breast Cancer

DTIC Science & Technology

2017-10-01

AWARD NUMBER: W81XWH-16-1-0461 TITLE: Novel Targeted Therapies for Inflammatory Breast Cancer PRINCIPAL INVESTIGATOR: Jose Silva CONTRACTING...CONTRACT NUMBER Novel Targeted Therapies for Inflammatory Breast Cancer 5b. GRANT NUMBER W81XWH-16-1-0461 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) l 5d...NOTES 14. ABSTRACT Inflammatory breast cancer (IBC, ~5% of all breast cancers ) is the most lethal form of breast cancer , presenting a 5- year

AGO/RISC-mediated antiviral RNA silencing in a plant in vitro system.

PubMed

Schuck, Jana; Gursinsky, Torsten; Pantaleo, Vitantonio; Burgyán, Jozsef; Behrens, Sven-Erik

2013-05-01

AGO/RISC-mediated antiviral RNA silencing, an important component of the plant's immune response against RNA virus infections, was recapitulated in vitro. Cytoplasmic extracts of tobacco protoplasts were applied that supported Tombusvirus RNA replication, as well as the formation of RNA-induced silencing complexes (RISC) that could be functionally reconstituted with various plant ARGONAUTE (AGO) proteins. For example, when RISC containing AGO1, 2, 3 or 5 were programmed with exogenous siRNAs that specifically targeted the viral RNA, endonucleolytic cleavages occurred and viral replication was inhibited. Antiviral RNA silencing was disabled by the viral silencing suppressor p19 when this was present early during RISC formation. Notably, with replicating viral RNA, only (+)RNA molecules were accessible to RISC, whereas (-)RNA replication intermediates were not. The vulnerability of viral RNAs to RISC activity also depended on the RNA structure of the target sequence. This was most evident when we characterized viral siRNAs (vsiRNAs) that were particularly effective in silencing with AGO1- or AGO2/RISC. These vsiRNAs targeted similar sites, suggesting that accessible parts of the viral (+)RNA may be collectively attacked by different AGO/RISC. The in vitro system was, hence, established as a valuable tool to define and characterize individual molecular determinants of antiviral RNA silencing.

Targeted therapies for the treatment of leukemia.

PubMed

Stull, Dawn Marie

2003-05-01

To review novel targeted therapies for the treatment of leukemia. Professional journals, books, and government publications. Nonspecific cytotoxic chemotherapeutic agents provide marginal therapeutic benefit and significant toxicity when used in the treatment of leukemia. There is a tremendous need for new therapies with increased efficacy and decreased adverse effects. Advances in molecular science, genetics, and immunology, along with improved laboratory technology, have led to the discovery of unique targets integral to the growth and proliferation of malignant cells which are providing the foundation for the development of a new generation of antitumor agents. Nurses must be prepared to educate patients, administer novel therapies, and manage side effects.

Meeting report: 28th International Conference on Antiviral Research in Rome, Italy.

PubMed

Vere Hodge, R Anthony

2015-11-01

The 28th International Conference on Antiviral Research (ICAR) was held in Rome, Italy from May 11 to 15, 2015. This article summarizes the principal invited lectures. Phillip Furman, the Elion award recipient, described the research leading to sofosbuvir. Dennis Liotta, who received the Holý award, described how an investigation into HIV entry inhibitors led to a new therapy for cancer patients. Erica Ollmann Saphire, winner of the Prusoff Young Investigator award, explored the world of viral proteins and how they remodel to perform different essential roles in viral replication. The keynote addresses, by Raffaele De Francesco and Michael Manns, reported on the remarkable progress made in the therapy of chronic HCV infections. A third keynote address, by Armand Sprecher, related the difficulties and successes of Médicins Sans Frontières in West Africa ravaged by the Ebola outbreak. There were three mini-symposia on RNA Viruses, Antiviral Chemistry and Emerging Viruses. There was a good collection of talks on RNA viruses (norovirus, rabies, dengue, HEV, HCV, and RSV). A highlight of the chemistry was the preparation of prodrugs for nucleotide triphosphates as this opens a door to new options. The third mini-symposium emphasized how research work in the antiviral area is continuing to expand and needs to do so with a sense of urgency. Although this meeting report covers only a few of the presentations, it aims to illustrate the great diversity of topics discussed at ICAR, bringing together knowledge and expertise from the whole spectrum of antiviral research. Copyright © 2015. Published by Elsevier B.V.

Antiviral Defenses in Plants through Genome Editing

PubMed Central

Romay, Gustavo; Bragard, Claude

2017-01-01

Plant–virus interactions based-studies have contributed to increase our understanding on plant resistance mechanisms, providing new tools for crop improvement. In the last two decades, RNA interference, a post-transcriptional gene silencing approach, has been used to induce antiviral defenses in plants with the help of genetic engineering technologies. More recently, the new genome editing systems (GES) are revolutionizing the scope of tools available to confer virus resistance in plants. The most explored GES are zinc finger nucleases, transcription activator-like effector nucleases, and clustered regularly interspaced short palindromic repeats/Cas9 endonuclease. GES are engineered to target and introduce mutations, which can be deleterious, via double-strand breaks at specific DNA sequences by the error-prone non-homologous recombination end-joining pathway. Although GES have been engineered to target DNA, recent discoveries of GES targeting ssRNA molecules, including virus genomes, pave the way for further studies programming plant defense against RNA viruses. Most of plant virus species have an RNA genome and at least 784 species have positive ssRNA. Here, we provide a summary of the latest progress in plant antiviral defenses mediated by GES. In addition, we also discuss briefly the GES perspectives in light of the rebooted debate on genetic modified organisms (GMOs) and the current regulatory frame for agricultural products involving the use of such engineering technologies. PMID:28167937

Changing strategies for target therapy in gastric cancer.

PubMed

Lee, Suk-Young; Oh, Sang Cheul

2016-01-21

In spite of a worldwide decrease in the incidence of gastric cancer, this malignancy still remains one of the leading causes of cancer mortality. Great efforts have been made to improve treatment outcomes in patients with metastatic gastric cancer, and the introduction of trastuzumab has greatly improved the overall survival. The trastuzumab treatment took its first step in opening the era of molecular targeted therapy, however several issues still need to be resolved to increase the efficacy of targeted therapy. Firstly, many patients with metastatic gastric cancer who receive trastuzumab in combination with chemotherapeutic agents develop resistance to the targeted therapy. Secondly, many clinical trials testing novel molecular targeted agents with demonstrated efficacy in other malignancies have failed to show benefit in patients with metastatic gastric cancer, suggesting the importance of the selection of appropriate indications according to molecular characteristics in application of targeted agents. Herein, we review the molecular targeted agents currently approved and in use, and clinical trials in patients with metastatic gastric cancer, and demonstrate the limitations and future direction in treatment of advanced gastric cancer.

Antiviral Defense Involves AGO4 in an Arabidopsis-Potexvirus Interaction.

PubMed

Brosseau, Chantal; El Oirdi, Mohamed; Adurogbangba, Ayooluwa; Ma, Xiaofang; Moffett, Peter

2016-11-01

In plants, RNA silencing regulates gene expression through the action of Dicer-like (DCL) and Argonaute (AGO) proteins via micro RNAs and RNA-dependent DNA methylation (RdDM). In addition, RNA silencing functions as an antiviral defense mechanism by targeting virus-derived double-stranded RNA. Plants encode multiple AGO proteins with specialized functions, including AGO4-like proteins that affect RdDM and AGO2, AGO5, and AGO1, which have antiviral activities. Here, we show that AGO4 is also required for defense against the potexvirus Plantago asiatica mosaic virus (PlAMV), most likely independent of RdDM components such as DCL3, Pol IV, and Pol V. Transient assays showed that AGO4 has direct antiviral activity on PlAMV and, unlike RdDM, this activity does not require nuclear localization of AGO4. Furthermore, although PlAMV infection causes a decrease in AGO4 expression, PlAMV causes a change in AGO4 localization from a largely nuclear to a largely cytoplasmic distribution. These results indicate an important role for AGO4 in targeting plant RNA viruses as well as demonstrating novel mechanisms of regulation of and by AGO4, independent of its canonical role in regulating gene expression by RdDM.

The Antiviral Mechanism of an Influenza A Virus Nucleoprotein-Specific Single-Domain Antibody Fragment

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hanke, Leo; Knockenhauer, Kevin E.; Brewer, R. Camille

Alpaca-derived single-domain antibody fragments (VHHs) that target the influenza A virus nucleoprotein (NP) can protect cells from infection when expressed in the cytosol. We found that one such VHH, αNP-VHH1, exhibits antiviral activity similar to that of Mx proteins by blocking nuclear import of incoming viral ribonucleoproteins (vRNPs) and viral transcription and replication in the nucleus. We determined a 3.2-Å crystal structure of αNP-VHH1 in complex with influenza A virus NP. The VHH binds to a nonconserved region on the body domain of NP, which has been associated with binding to host factors and serves as a determinant of hostmore » range. Several of the NP/VHH interface residues determine sensitivity of NP to antiviral Mx GTPases. The structure of the NP/αNP-VHH1 complex affords a plausible explanation for the inhibitory properties of the VHH and suggests a rationale for the antiviral properties of Mx proteins. Such knowledge can be leveraged for much-needed novel antiviral strategies. IMPORTANCEInfluenza virus strains can rapidly escape from protection afforded by seasonal vaccines or acquire resistance to available drugs. Additional ways to interfere with the virus life cycle are therefore urgently needed. The influenza virus nucleoprotein is one promising target for antiviral interventions. We have previously isolated alpaca-derived single-domain antibody fragments (VHHs) that protect cells from influenza virus infection if expressed intracellularly. We show here that one such VHH exhibits antiviral activities similar to those of proteins of the cellular antiviral defense (Mx proteins). We determined the three-dimensional structure of this VHH in complex with the influenza virus nucleoprotein and identified the interaction site, which overlaps regions that determine sensitivity of the virus to Mx proteins. Our data define a new vulnerability of influenza virus, help us to better understand the cellular antiviral mechanisms, and provide a well

Targeted cancer therapy--are the days of systemic chemotherapy numbered?

PubMed

Joo, Won Duk; Visintin, Irene; Mor, Gil

2013-12-01

Targeted therapy or molecular targeted therapy has been defined as a type of treatment that blocks the growth of cancer cells by interfering with specific cell molecules required for carcinogenesis and tumor growth, rather than by simply interfering with all rapidly dividing cells as with traditional chemotherapy. There is a growing number of FDA approved monoclonal antibodies and small molecules targeting specific types of cancer suggestive of the growing relevance of this therapeutic approach. Targeted cancer therapies, also referred to as "Personalized Medicine", are being studied for use alone, in combination with other targeted therapies, and in combination with chemotherapy. The objective of personalized medicine is the identification of patients that would benefit from a specific treatment based on the expression of molecular markers. Examples of this approach include bevacizumab and olaparib, which have been designated as promising targeted therapies for ovarian cancer. Combinations of trastuzumab with pertuzumab, or T-DM1 and mTOR inhibitors added to an aromatase inhibitor are new therapeutic strategies for breast cancer. Although this approach has been seen as a major step in the expansion of personalized medicine, it has substantial limitations including its high cost and the presence of serious adverse effects. The Cancer Genome Atlas is a useful resource to identify novel and more effective targets, which may help to overcome the present limitations. In this review we will discuss the clinical outcome of some of these new therapies with a focus on ovarian and breast cancer. We will also discuss novel concepts in targeted therapy, the target of cancer stem cells. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Recent Advances in Targeted Therapy for Glioma.

PubMed

Lin, Lin; Cai, Jinquan; Jiang, Chuanlu

2017-01-01

Gliomas are the most common primary malignant brain tumors, which have a universally fatal outcome. Current standard treatment for glioma patients is surgical removal followed by radiotherapy and adjuvant chemotherapy. Due to therapeutic resistance and tumor recurrence, efforts are ongoing to identify the molecules that are fundamental to regulate the tumor progression and provide additional methods for individual treatment of glioma patients. By studying the initiation and maintenance of glioma, studies focused on the targets of tyrosine kinase receptors including EGFR, PDGFR and other crucial signal pathways such as PI3K/AKT and RAS/RAF/MAPK pathway. Furthermore, recent advances in targeting immunotherapy and stem cell therapy also brought numerous strategies to glioma treatment. This article reviewed the researches focused on the advanced strategies of various target therapies for improving the glioma treatment efficacy, and discussed the challenges and future directions for glioma therapy. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Advances of Molecular Targeted Therapy in Gastric Cancer.

PubMed

Cetin, Bulent; Gumusay, Ozge; Cengiz, Mustafa; Ozet, Ahmet

2016-06-01

Gastric cancer is the second most common cause of cancer-related death in the world, and its prognosis remains poor with a median overall survival of 12 months for advanced disease. Advances in the understanding of molecular genetics have led to the development of directed molecular targeted therapy in gastric cancer, leading to improve patient outcomes and quality of life. In the treatment of human epidermal growth factor receptor 2 (HER2)-positive gastric cancer, the addition of trastuzumab significantly improves survival in the first-line setting of therapy. Ramucirumab, an antibody directed against vascular endothelial growth factor receptor 2, significantly improved progression-free and overall survival and has been approved for second-line treatment of gastric cancer. Anti-mesenchymal-epithelial transition (c-MET), mammalian target of rapamycin inhibitors, and polo-like kinase 1 inhibitors are under investigation as a novel therapeutic option for the treatment of gastric cancer. The novel therapies target the key immune checkpoint interaction between a T cell co-inhibitory receptor called programmed death 1 (PD-1) and one of its immunosuppressive ligands, PD-L1. This article reviews molecular targeted therapies in gastric cancer, in light of recent advances.

Bacteriophage-Derived Vectors for Targeted Cancer Gene Therapy

PubMed Central

Pranjol, Md Zahidul Islam; Hajitou, Amin

2015-01-01

Cancer gene therapy expanded and reached its pinnacle in research in the last decade. Both viral and non-viral vectors have entered clinical trials, and significant successes have been achieved. However, a systemic administration of a vector, illustrating safe, efficient, and targeted gene delivery to solid tumors has proven to be a major challenge. In this review, we summarize the current progress and challenges in the targeted gene therapy of cancer. Moreover, we highlight the recent developments of bacteriophage-derived vectors and their contributions in targeting cancer with therapeutic genes following systemic administration. PMID:25606974

Bacteriophage-derived vectors for targeted cancer gene therapy.

PubMed

Pranjol, Md Zahidul Islam; Hajitou, Amin

2015-01-19

Cancer gene therapy expanded and reached its pinnacle in research in the last decade. Both viral and non-viral vectors have entered clinical trials, and significant successes have been achieved. However, a systemic administration of a vector, illustrating safe, efficient, and targeted gene delivery to solid tumors has proven to be a major challenge. In this review, we summarize the current progress and challenges in the targeted gene therapy of cancer. Moreover, we highlight the recent developments of bacteriophage-derived vectors and their contributions in targeting cancer with therapeutic genes following systemic administration.

ESCMID Study Group for Infections in Compromised Hosts (ESGICH) Consensus Document on the safety of targeted and biological therapies: an infectious diseases perspective (Soluble immune effector molecules [II]: agents targeting interleukins, immunoglobulins and complement factors).

PubMed

Winthrop, K L; Mariette, X; Silva, J T; Benamu, E; Calabrese, L H; Dumusc, A; Smolen, J S; Aguado, J M; Fernández-Ruiz, M

2018-06-01

The present review is part of the ESCMID Study Group for Infections in Compromised Hosts (ESGICH) Consensus Document on the safety of targeted and biological therapies. To review, from an Infectious Diseases perspective, the safety profile of agents targeting interleukins, immunoglobulins and complement factors and to suggest preventive recommendations. Computer-based MEDLINE searches with MeSH terms pertaining to each agent or therapeutic family. Patients receiving interleukin-1 (IL-1) -targeted (anakinra, canakinumab or rilonacept) or IL-5-targeted (mepolizumab) agents have a moderate risk of infection and no specific prevention strategies are recommended. The use of IL-6/IL-6 receptor-targeted agents (tocilizumab and siltuximab) is associated with a risk increase similar to that observed with anti-tumour necrosis factor-α agents. IL-12/23-targeted agents (ustekinumab) do not seem to pose a meaningful risk of infection, although screening for latent tuberculosis infection may be considered and antiviral prophylaxis should be given to hepatitis B surface antigen-positive patients. Therapy with IL-17-targeted agents (secukinumab, brodalumab and ixekizumab) may result in the development of mild-to-moderate mucocutaneous candidiasis. Pre-treatment screening for Strongyloides stercoralis and other geohelminths should be considered in patients who come from areas where these are endemic who are receiving IgE-targeted agents (omalizumab). C5-targeted agents (eculizumab) are associated with a markedly increased risk of infection due to encapsulated bacteria, particularly Neisseria spp. Meningococcal vaccination and chemoprophylaxis must be administered 2-4 weeks before initiating eculizumab. Patients with high-risk behaviours and their partners should also be screened for gonococcal infection. Preventive strategies are particularly encouraged to minimize the occurrence of neisserial infection associated with eculizumab. Copyright © 2018 European Society of Clinical

Complete cure of persistent virus infections by antiviral siRNAs.

PubMed

Saulnier, Aure; Pelletier, Isabelle; Labadie, Karine; Colbère-Garapin, Florence

2006-01-01

Small interfering RNAs (siRNAs) have been developed as antiviral agents for mammalian cells. The capacity of specific siRNAs to prevent virus infections has been demonstrated, and there is evidence that these new antiviral agents could have a partial therapeutic effect a few days after infection. We investigated the possibility of curing a persistent infection, several months after becoming established, using an in vitro model of persistent poliovirus (PV) infection in HEp-2 cells. Despite high virus titers and the presence of PV mutants, repeated treatment with a mixture of two siRNAs targeting both noncoding and coding regions, one of them in a highly conserved region, resulted in the complete cure of the majority of persistently infected cultures. No escape mutants emerged in treated cultures. The antiviral effect of specific siRNAs, consistent with a mechanism of RNA interference, correlated with a decrease in the amount of viral RNA, until its complete disappearance, resulting in cultures cured of virions and viral RNA.

AGO/RISC-mediated antiviral RNA silencing in a plant in vitro system

PubMed Central

Schuck, Jana; Gursinsky, Torsten; Pantaleo, Vitantonio; Burgyán, Jozsef; Behrens, Sven-Erik

2013-01-01

AGO/RISC-mediated antiviral RNA silencing, an important component of the plant’s immune response against RNA virus infections, was recapitulated in vitro. Cytoplasmic extracts of tobacco protoplasts were applied that supported Tombusvirus RNA replication, as well as the formation of RNA-induced silencing complexes (RISC) that could be functionally reconstituted with various plant ARGONAUTE (AGO) proteins. For example, when RISC containing AGO1, 2, 3 or 5 were programmed with exogenous siRNAs that specifically targeted the viral RNA, endonucleolytic cleavages occurred and viral replication was inhibited. Antiviral RNA silencing was disabled by the viral silencing suppressor p19 when this was present early during RISC formation. Notably, with replicating viral RNA, only (+)RNA molecules were accessible to RISC, whereas (−)RNA replication intermediates were not. The vulnerability of viral RNAs to RISC activity also depended on the RNA structure of the target sequence. This was most evident when we characterized viral siRNAs (vsiRNAs) that were particularly effective in silencing with AGO1- or AGO2/RISC. These vsiRNAs targeted similar sites, suggesting that accessible parts of the viral (+)RNA may be collectively attacked by different AGO/RISC. The in vitro system was, hence, established as a valuable tool to define and characterize individual molecular determinants of antiviral RNA silencing. PMID:23535144

Mucin-based targeted pancreatic cancer therapy.

PubMed

Torres, Maria P; Chakraborty, Subhankar; Souchek, Joshua; Batra, Surinder K

2012-01-01

The prognosis of pancreatic cancer (PC) patients is very poor with a five-year survival of less than 5%. One of the major challenges in developing new therapies for PC is the lack of expression of specific markers by pancreatic tumor cells. Mucins are heavily Oglycosylated proteins characterized by the presence of short stretches of amino acid sequences repeated several times in tandem. The expression of several mucins including MUC1, MUC4, MUC5AC, and MUC16 is strongly upregulated in PC. Recent studies have also demonstrated a link between the aberrant expression and differential overexpression of mucin glycoproteins to the initiation, progression, and poor prognosis of the disease. These studies have led to increasing recognition of mucins as potential diagnostic markers and therapeutic targets in PC. In this focused review we present an overview of the therapies targeting mucins in PC, including immunotherapy (i.e. vaccines, antibodies, and radioimmunoconjugates), gene therapy, and other novel therapeutic strategies.

Imatinib: A Breakthrough of Targeted Therapy in Cancer

PubMed Central

Iqbal, Naveed

2014-01-01

Deregulated protein tyrosine kinase activity is central to the pathogenesis of human cancers. Targeted therapy in the form of selective tyrosine kinase inhibitors (TKIs) has transformed the approach to management of various cancers and represents a therapeutic breakthrough. Imatinib was one of the first cancer therapies to show the potential for such targeted action. Imatinib, an oral targeted therapy, inhibits tyrosine kinases specifically BCR-ABL, c-KIT, and PDGFRA. Apart from its remarkable success in CML and GIST, Imatinib benefits various other tumors caused by Imatinib-specific abnormalities of PDGFR and c-KIT. Imatinib has also been proven to be effective in steroid-refractory chronic graft-versus-host disease because of its anti-PDGFR action. This paper is a comprehensive review of the role of Imatinib in oncology. PMID:24963404

Improving patient outcomes to targeted therapies in melanoma.

PubMed

Eroglu, Zeynep; Smalley, Keiran S M; Sondak, Vernon K

2016-06-01

The arrival of targeted therapies has led to significant improvements in clinical outcomes for patients with BRAFV600 mutated advanced melanoma over the past five years. In several clinical trials, BRAF and MEK inhibitors have shown improvement in progression free and overall survival, along with much higher tumor response rates in comparison to chemotherapy, with the combination of these drugs superior to monotherapy. These agents are also being tested in earlier-stage patients, in addition to alternative dosing regimens and in combinations with other therapeutics. Efforts are also ongoing to expand the success found with targeted therapies to other subtypes of melanoma, including NRAS and c-kit mutated melanomas, uveal melanomas, and BRAF/NRAS wild type melanomas. Expert Commentary: We aim to provide an overview of clinical outcomes with targeted therapies in melanoma patients.

Target marketing strategies for occupational therapy entrepreneurs.

PubMed

Kautzmann, L N; Kautzmann, F N; Navarro, F H

1989-01-01

Understanding marketing techniques is one of the skills needed by successful entre renews. Target marketing is an effective method for occupational therapy entrepreneurs to use in determining when and where to enter the marketplace. The two components of target marketing, market segmentation and the development of marketing mix strategies for each identified market segment, are described. The Profife of Attitudes Toward Health Care (PATH) method of psychographic market segmentation of health care consumers is presented. Occupational therapy marketing mix strategies for each PATH consumer group are delineated and compatible groupings of market segments are suggested.

Synaptic transmission and the susceptibility of HIV infection to anti-viral drugs

NASA Astrophysics Data System (ADS)

Komarova, Natalia L.; Levy, David N.; Wodarz, Dominik

2013-07-01

Cell-to-cell viral transmission via virological synapses has been argued to reduce susceptibility of the virus population to anti-viral drugs through multiple infection of cells, contributing to low-level viral persistence during therapy. Using a mathematical framework, we examine the role of synaptic transmission in treatment susceptibility. A key factor is the relative probability of individual virions to infect a cell during free-virus and synaptic transmission, a currently unknown quantity. If this infection probability is higher for free-virus transmission, then treatment susceptibility is lowest if one virus is transferred per synapse, and multiple infection of cells increases susceptibility. In the opposite case, treatment susceptibility is minimized for an intermediate number of virions transferred per synapse. Hence, multiple infection via synapses does not simply lower treatment susceptibility. Without further experimental investigations, one cannot conclude that synaptic transmission provides an additional mechanism for the virus to persist at low levels during anti-viral therapy.

Stem cell based anti-HIV Gene therapy

PubMed Central

Kitchen, Scott G.; Shimizu, Saki; An, Dong Sung

2011-01-01

Human stem cell-based therapeutic intervention strategies for treating HIV infection have recently undergone a renaissance as a major focus of investigation. Unlike most conventional antiviral therapies, genetically engineered hematopoietic stem cells possess the capacity for prolonged self-renewal that would continuously produce protected immune cells to fight against HIV. A successful strategy therefore has the potential to stably control and ultimately eradicate HIV from patients by a single or minimal treatment. Recent progress in the development of new technologies and clinical trials sets the stage for the current generation of gene therapy approaches to combat HIV infection. In this review, we will discuss two major approaches that are currently underway in the development of stem cell-based gene therapy to target HIV: One that focuses on the protection of cells from productive infection with HIV, and the other that focuses on targeting immune cells to directly combat HIV infection. PMID:21247612

Engineering a Therapeutic Lectin by Uncoupling Mitogenicity from Antiviral Activity

PubMed Central

Swanson, Michael D.; Boudreaux, Daniel M.; Salmon, Loïc; Chugh, Jeetender; Winter, Harry C.; Meagher, Jennifer L.; André, Sabine; Murphy, Paul V.; Oscarson, Stefan; Roy, René; King, Steven; Kaplan, Mark H.; Goldstein, Irwin J.; Tarbet, E. Bart; Hurst, Brett L.; Smee, Donald F.; de la Fuente, Cynthia; Hoffmann, Hans-Heinrich; Xue, Yi; Rice, Charles M.; Schols, Dominique; Garcia, J. Victor; Stuckey, Jeanne A.; Gabius, Hans-Joachim; Al-Hashimi, Hashim M.; Markovitz, David M.

2015-01-01

Summary A key effector route of the Sugar Code involves lectins that exert crucial regulatory controls by targeting distinct cellular glycans. We demonstrate that a single amino acid substitution in a banana lectin, replacing histidine 84 with a threonine, significantly reduces its mitogenicity while preserving its broad-spectrum antiviral potency. X-ray crystallography, NMR spectroscopy, and glycocluster assays reveal that loss of mitogenicity is strongly correlated with loss of pi-pi stacking between aromatic amino acids H84 and Y83, which removes a wall separating two carbohydrate binding sites, thus diminishing multivalent interactions. On the other hand, monovalent interactions and antiviral activity are preserved by retaining other wild-type conformational features and possibly through unique contacts involving the T84 side chain. Through such fine-tuning, target selection and downstream effects of a lectin can be modulated so as to knock down one activity while preserving another, thus providing tools for therapeutics and for understanding the Sugar Code. PMID:26496612

Interferon-based anti-viral therapy for hepatitis C virus infection after renal transplantation: an updated meta-analysis.

PubMed

Wei, Fang; Liu, Junying; Liu, Fen; Hu, Huaidong; Ren, Hong; Hu, Peng

2014-01-01

Hepatitis C virus (HCV) infection is highly prevalent in renal transplant (RT) recipients. Currently, interferon-based (IFN-based) antiviral therapies are the standard approach to control HCV infection. In a post-transplantation setting, however, IFN-based therapies appear to have limited efficacy and their use remains controversial. The present study aimed to evaluate the efficacy and safety of IFN-based therapies for HCV infection post RT. We searched Pubmed, Embase, Web of Knowledge, and The Cochrane Library (1997-2013) for clinical trials in which transplant patients were given Interferon (IFN), pegylated interferon (PEG), interferon plus ribavirin (IFN-RIB), or pegylated interferon plus ribavirin (PEG-RIB). The Sustained Virological Response (SVR) and/or drop-out rates were the primary outcomes. Summary estimates were calculated using the random-effects model of DerSimonian and Laird, with heterogeneity and sensitivity analysis. We identified 12 clinical trials (140 patients in total). The summary estimate for SVR rate, drop-out rate and graft rejection rate was 26.6% (95%CI, 15.0-38.1%), 21.1% (95% CI, 10.9-31.2%) and 4% (95%CI: 0.8%-7.1%), respectively. The overall SVR rate in PEG-based and standard IFN-based therapy was 40.6% (24/59) and 20.9% (17/81), respectively. The most frequent side-effect requiring discontinuation of treatment was graft dysfunction (14 cases, 45.1%). Meta-regression analysis showed the covariates included contribute to the heterogeneity in the SVR logit rate, but not in the drop-out logit rate. The sensitivity analyses by the random model yielded very similar results to the fixed-effects model. IFN-based therapy for HCV infection post RT has poor efficacy and limited safety. PEG-based therapy is a more effective approach for treating HCV infection post-RT than standard IFN-based therapy. Future research is required to develop novel strategies to improve therapeutic efficacy and tolerability, and reduce the liver-related morbidity and

Steroid plus antiviral treatment for Bell's palsy.

PubMed

Kang, H M; Jung, S Y; Byun, J Y; Park, M S; Yeo, S G

2015-05-01

The effectiveness of antiviral agents for the treatment of Bell's palsy is uncertain. We evaluated whether a steroid with an antiviral agent (S + A group) provided better recovery outcomes than a steroid alone (S group) in patients with Bell's palsy. A total of 1342 patients diagnosed with Bell's palsy who visited the Kyung Hee Medical Center in Seoul, Korea, from 2002 to 2012 were included in this study. Patients in the S + A group were treated with prednisolone and antiviral agents (n = 569) and those in the S group with prednisolone alone (n = 773). Outcomes were measured using the House-Brackmann (HB) scale according to age, initial disease severity, electroneurography (ENoG) findings and underlying comorbidities. The rate of recovery (HB grades I and II) with initially severe Bell's palsy (HB grades V and VI) was higher in the S + A than in the S group (P = 0.001). However, the rates of recovery were similar with initially moderate palsy (HB grades II-IV) (P = 0.502). In patients classified according to age and ENoG-determined severity of palsy, the overall recovery rate was higher in the S + A than in the S group, but the differences were not statistically significant (P > 0.05 for both). The recovery rate without diabetes mellitus (DM) and hypertension (HTN) was higher in the S + A group than in the S group (P = 0.031). But in the patients with HTN and DM, the difference in recovery rates between the S + A and S groups was not statistically significant (P = 0.805). Treatment with a steroid plus antiviral agent resulted in significantly higher recovery rates than steroid therapy alone in patients with initially severe Bell's palsy and without either HTN or DM, and a nonsignificant trend towards higher recovery rates in all patients with Bell's palsy in this study. Antiviral agents may therefore help in the treatment of Bell's palsy. © 2014 The Association for the Publication of the Journal of Internal Medicine.

Corticosteroids vs corticosteroids plus antiviral agents in the treatment of Bell palsy: a systematic review and meta-analysis.

PubMed

Goudakos, John K; Markou, Konstantinos D

2009-06-01

To review systematically and meta-analyze the results of all randomized controlled trials (RCTs) for the treatment of patients with Bell palsy with corticosteroids vs corticosteroids plus antiviral agents. A MEDLINE, EMBASE, Cochrane Library, and CENTRAL database search, followed by extensive hand-searching for the identification of relevant studies. No time and language limitations were applied. Prospective RCTs on the treatment of patients with Bell palsy. Odds ratios (ORs), 95% confidence intervals (CIs), and tests for heterogeneity were reported. Five studies were eventually identified and systematically reviewed. Meta-analysis was performed for 4 studies. Regarding the complete recovery rate of facial nerve paralysis 3 months after initiation of therapy, the current systematic review and meta-analysis suggests that the addition of an antiviral agent does not provide any benefit (OR, 1.03 [95% CI, 0.74-1.42]; P = .88). The same conclusion emerged at posterior (fourth, sixth, and ninth) months of assessment. Subgroup analysis, conducted on the basis of time point of therapy initiation, type of antiviral agent, and blindness of assessments did not change the results obtained. The occurrence rate of adverse effects attributable to therapy choice was not significantly different between patients receiving corticosteroids and those following combined treatment. The present systematic review and meta-analysis, based on the currently available evidence, suggests that the addition of an antiviral agent to corticosteroids for the treatment of Bell palsy is not associated with an increase in the complete recovery rate of the facial motor function.

Targeted prostaglandin E2 inhibition enhances antiviral immunity through induction of type I interferon and apoptosis in macrophages.

PubMed

Coulombe, François; Jaworska, Joanna; Verway, Mark; Tzelepis, Fanny; Massoud, Amir; Gillard, Joshua; Wong, Gary; Kobinger, Gary; Xing, Zhou; Couture, Christian; Joubert, Philippe; Fritz, Jörg H; Powell, William S; Divangahi, Maziar

2014-04-17

Aspirin gained tremendous popularity during the 1918 Spanish Influenza virus pandemic, 50 years prior to the demonstration of their inhibitory action on prostaglandins. Here, we show that during influenza A virus (IAV) infection, prostaglandin E2 (PGE2) was upregulated, which led to the inhibition of type I interferon (IFN) production and apoptosis in macrophages, thereby causing an increase in virus replication. This inhibitory role of PGE2 was not limited to innate immunity, because both antigen presentation and T cell mediated immunity were also suppressed. Targeted PGE2 suppression via genetic ablation of microsomal prostaglandin E-synthase 1 (mPGES-1) or by the pharmacological inhibition of PGE2 receptors EP2 and EP4 substantially improved survival against lethal IAV infection whereas PGE2 administration reversed this phenotype. These data demonstrate that the mPGES-1-PGE2 pathway is targeted by IAV to evade host type I IFN-dependent antiviral immunity. We propose that specific inhibition of PGE2 signaling might serve as a treatment for IAV. Copyright © 2014 Elsevier Inc. All rights reserved.

ZFP36 RNA-binding proteins restrain T-cell activation and anti-viral immunity.

PubMed

Moore, Michael J; Blachere, Nathalie E; Fak, John J; Park, Christopher Y; Sawicka, Kirsty; Parveen, Salina; Zucker-Scharff, Ilana; Moltedo, Bruno; Rudensky, Alexander Y; Darnell, Robert B

2018-05-31

Dynamic post-transcriptional control of RNA expression by RNA-binding proteins (RBPs) is critical during immune response. ZFP36 RBPs are prominent inflammatory regulators linked to autoimmunity and cancer, but functions in adaptive immunity are less clear. We used HITS-CLIP to define ZFP36 targets in mouse T cells, revealing unanticipated actions in regulating T cell activation, proliferation, and effector functions. Transcriptome and ribosome profiling showed that ZFP36 represses mRNA target abundance and translation, notably through novel AU-rich sites in coding sequence. Functional studies revealed that ZFP36 regulates early T cell activation kinetics cell autonomously, by attenuating activation marker expression, limiting T cell expansion, and promoting apoptosis. Strikingly, loss of ZFP36 in vivo accelerated T cell responses to acute viral infection and enhanced anti-viral immunity. These findings uncover a critical role for ZFP36 RBPs in restraining T cell expansion and effector functions, and suggest ZFP36 inhibition as a strategy to enhance immune-based therapies. © 2018, Moore et al.

Smurf2 negatively modulates RIG-I-dependent antiviral response by targeting VISA/MAVS for ubiquitination and degradation.

PubMed

Pan, Yu; Li, Rui; Meng, Jun-Ling; Mao, He-Ting; Zhang, Yu; Zhang, Jun

2014-05-15

VISA (also known as MAVS, Cardif, IPS-1) is the essential adaptor protein for virus-induced activation of IFN regulatory factors 3 and 7 and production of type I IFNs. Understanding the regulatory mechanisms for VISA will provide detailed insights into the positive or negative regulation of innate immune responses. In this study, we identified Smad ubiquitin regulatory factor (Smurf) 2, one of the Smad ubiquitin regulator factor proteins, as an important negative regulator of virus-triggered type I IFN signaling, which targets at the VISA level. Overexpression of Smurf2 inhibits virus-induced IFN-β and IFN-stimulated response element activation. The E3 ligase defective mutant Smurf2/C716A loses the ability to suppress virus-induced type I IFN signaling, suggesting that the negative regulation is dependent on the ubiquitin E3 ligase activity of Smurf2. Further studies demonstrated that Smurf2 interacted with VISA and targeted VISA for K48-linked ubiquitination, which promoted the degradation of VISA. Consistently, knockout or knockdown of Smurf2 expression therefore promoted antiviral signaling, which was correlated with the increase in protein stability of VISA. Our findings suggest that Smurf2 is an important nonredundant negative regulator of virus-triggered type I IFN signaling by targeting VISA for K48-linked ubiquitination and degradation.

Cell-based flavivirus infection (CFI) assay for the evaluation of dengue antiviral candidates using high-content imaging.

PubMed

Tan, Kah Hin; Ki, Kitti Chan Wing; Watanabe, Satoru; Vasudevan, Subhash G; Krishnan, Manoj

2014-01-01

Large-scale screening of antiviral compounds that target dengue virus life cycle requires a robust cell-based assay that is rapid, easy to conduct, and sensitive enough to be able to assess viral infectivity and cell viability so that antiviral efficacy can be measured. In this chapter we describe a method that uses high-content imaging to evaluate the in vitro antiviral efficacy in a modification to the cell-based flavivirus immunodetection (CFI) assay that was described previously in Wang et al. (Antimicrob Agents Chemother 53(5):1823-1831, 2009).

Update On Emerging Antivirals For The Management Of Herpes Simplex Virus Infections: A Patenting Perspective

PubMed Central

Vadlapudi, Aswani D.; Vadlapatla, Ramya K.; Mitra, Ashim K.

2015-01-01

Herpes simplex virus (HSV) infections can be treated efficiently by the application of antiviral drugs. The herpes family of viruses is responsible for causing a wide variety of diseases in humans. The standard therapy for the management of such infections includes acyclovir (ACV) and penciclovir (PCV) with their respective prodrugs valaciclovir and famciclovir. Though effective, long term prophylaxis with the current drugs leads to development of drug-resistant viral isolates, particularly in immunocompromised patients. Moreover, some drugs are associated with dose-limiting toxicities which limit their further utility. Therefore, there is a need to develop new antiherpetic compounds with different mechanisms of action which will be safe and effective against emerging drug resistant viral isolates. Significant advances have been made towards the design and development of novel antiviral therapeutics during the last decade. As evident by their excellent antiviral activities, pharmaceutical companies are moving forward with several new compounds into various phases of clinical trials. This review provides an overview of structure and life cycle of HSV, progress in the development of new therapies, update on the advances in emerging therapeutics under clinical development and related recent patents for the treatment of Herpes simplex virus infections. PMID:23331181

Adenovirus infection in pediatric transplant recipients: are effective antiviral agents coming our way?

PubMed

Lopez, Santiago M C; Michaels, Marian G; Green, Michael

2018-05-24

Adenoviruses (AdVs) infection is a self-limited disease in the majority of immunocompetent children and adults, but can cause disseminated and life-threatening illness in immunocompromised hosts. This article will discuss therapeutic strategies for AdV infection in the pediatrics transplant recipient. Currently, there is no FDA approved antiviral therapy for AdV infection. Accordingly, the primary initial therapy would be decreasing immunosuppression, whenever possible. Cidofovir (CDV) is an antiviral drug whose use has been associated with significant reductions of AdV viral load and, in some series improved survival in recipients of solid organ transplant (SOT) and hematopoietic stem cell transplant (HSCT). However, its use is also associated with significant toxicity. Brincidofovir (BCV) is a lipid formulation of CDV, which has an improved oral bioavailability and favorable toxicity profile compared with CDV. However, studies have only shown modest benefit from BCV for AdV disease or viremia. Immunotherapy is a growing field in the management of this virus infection on HSCT patients with promising results. Current evidence support the use of CDV and BCV, as rescue therapy, on SOT and HSCT transplant patients. Immunotherapy had only been proven successful in HSCT patients, as an option for refractory cases or rescue therapy for AdV infection.

Flaviviral NS4b, chameleon and jack-in-the-box roles in viral replication and pathogenesis, and a molecular target for antiviral intervention.

PubMed

Zmurko, Joanna; Neyts, Johan; Dallmeier, Kai

2015-07-01

Dengue virus and other flaviviruses such as the yellow fever, West Nile, and Japanese encephalitis viruses are emerging vector-borne human pathogens that affect annually more than 100 million individuals and that may cause debilitating and potentially fatal hemorrhagic and encephalitic diseases. Currently, there are no specific antiviral drugs for the treatment of flavivirus-associated disease. A better understanding of the flavivirus-host interactions during the different events of the flaviviral life cycle may be essential when developing novel antiviral strategies. The flaviviral non-structural protein 4b (NS4b) appears to play an important role in flaviviral replication by facilitating the formation of the viral replication complexes and in counteracting innate immune responses such as the following: (i) type I IFN signaling; (ii) RNA interference; (iii) formation of stress granules; and (iv) the unfolded protein response. Intriguingly, NS4b has recently been shown to constitute an excellent target for the selective inhibition of flavivirus replication. We here review the current knowledge on NS4b. © 2015 The Authors. Reviews in Medical Virology published by John Wiley & Sons Ltd.

Chemiluminescent activation of the antiviral activity of hypericin: a molecular flashlight.

PubMed Central

Carpenter, S; Fehr, M J; Kraus, G A; Petrich, J W

1994-01-01

Hypericin is a naturally occurring photosensitizer that displays potent antiviral activity in the presence of light. The absence of light in many regions of the body may preclude the use of hypericin and other photosensitizers as therapeutic compounds for the treatment of viral infections in vivo. The chemiluminescent oxidation of luciferin by the luciferase from the North American firefly Photinus pyralis was found to generate sufficiently intense and long-lived emission to induce antiviral activity of hypericin. Light-induced virucidal activity of hypericin was demonstrated against equine infectious anemia virus, a lentivirus structurally, genetically, and antigenically related to the human immunodeficiency virus. The implications for exploiting chemiluminescence as a "molecular flashlight" for effecting photodynamic therapy against virus-infected cells and tumor cells are discussed. PMID:7991618

Imaging analysis of nuclear antiviral factors through direct detection of incoming adenovirus genome complexes.

PubMed

Komatsu, Tetsuro; Will, Hans; Nagata, Kyosuke; Wodrich, Harald

2016-04-22

Recent studies involving several viral systems have highlighted the importance of cellular intrinsic defense mechanisms through nuclear antiviral proteins that restrict viral propagation. These factors include among others components of PML nuclear bodies, the nuclear DNA sensor IFI16, and a potential restriction factor PHF13/SPOC1. For several nuclear replicating DNA viruses, it was shown that these factors sense and target viral genomes immediately upon nuclear import. In contrast to the anticipated view, we recently found that incoming adenoviral genomes are not targeted by PML nuclear bodies. Here we further explored cellular responses against adenoviral infection by focusing on specific conditions as well as additional nuclear antiviral factors. In line with our previous findings, we show that neither interferon treatment nor the use of specific isoforms of PML nuclear body components results in co-localization between incoming adenoviral genomes and the subnuclear domains. Furthermore, our imaging analyses indicated that neither IFI16 nor PHF13/SPOC1 are likely to target incoming adenoviral genomes. Thus our findings suggest that incoming adenoviral genomes may be able to escape from a large repertoire of nuclear antiviral mechanisms, providing a rationale for the efficient initiation of lytic replication cycle. Copyright © 2016 Elsevier Inc. All rights reserved.

Use of influenza antiviral agents by ambulatory care clinicians during the 2012-2013 influenza season.

PubMed

Havers, Fiona; Thaker, Swathi; Clippard, Jessie R; Jackson, Michael; McLean, Huong Q; Gaglani, Manjusha; Monto, Arnold S; Zimmerman, Richard K; Jackson, Lisa; Petrie, Josh G; Nowalk, Mary Patricia; Moehling, Krissy K; Flannery, Brendan; Thompson, Mark G; Fry, Alicia M

2014-09-15

Early antiviral treatment (≤2 days since illness onset) of influenza reduces the probability of influenza-associated complications. Early empiric antiviral treatment is recommended for those with suspected influenza at higher risk for influenza complications regardless of their illness severity. We describe antiviral receipt among outpatients with acute respiratory illness (ARI) and antibiotic receipt among patients with influenza. We analyzed data from 5 sites in the US Influenza Vaccine Effectiveness Network Study during the 2012-2013 influenza season. Subjects were outpatients aged ≥6 months with ARI defined by cough of ≤7 days' duration; all were tested for influenza by polymerase chain reaction (PCR). Medical history and prescription information were collected by medical and pharmacy records. Four sites collected prescribing data on 3 common antibiotics (amoxicillin-clavulanate, amoxicillin, and azithromycin). Of 6766 enrolled ARI patients, 509 (7.5%) received an antiviral prescription. Overall, 2366 (35%) had PCR-confirmed influenza; 355 (15%) of those received an antiviral prescription. Among 1021 ARI patients at high risk for influenza complications (eg, aged <2 years or ≥65 years or with ≥1 chronic medical condition) presenting to care ≤2 days from symptom onset, 195 (19%) were prescribed an antiviral medication. Among participants with PCR-confirmed influenza and antibiotic data, 540 of 1825 (30%) were prescribed 1 of 3 antibiotics; 297 of 1825 (16%) were prescribed antiviral medications. Antiviral treatment was prescribed infrequently among outpatients with influenza for whom therapy would be most beneficial; in contrast, antibiotic prescribing was more frequent. Continued efforts to educate clinicians on appropriate antibiotic and antiviral use are essential to improve healthcare quality. Published by Oxford University Press on behalf of the Infectious Diseases Society of America 2014. This work is written by (a) US Government employee

Antiviral treatment is more effective than smallpox vaccination upon lethal monkeypox virus infection.

PubMed

Stittelaar, Koert J; Neyts, Johan; Naesens, Lieve; van Amerongen, Geert; van Lavieren, Rob F; Holý, Antonin; De Clercq, Erik; Niesters, Hubert G M; Fries, Edwin; Maas, Chantal; Mulder, Paul G H; van der Zeijst, Ben A M; Osterhaus, Albert D M E

2006-02-09

There is concern that variola virus, the aetiological agent of smallpox, may be used as a biological weapon. For this reason several countries are now stockpiling (vaccinia virus-based) smallpox vaccine. Although the preventive use of smallpox vaccination has been well documented, little is known about its efficacy when used after exposure to the virus. Here we compare the effectiveness of (1) post-exposure smallpox vaccination and (2) antiviral treatment with either cidofovir (also called HPMPC or Vistide) or with a related acyclic nucleoside phosphonate analogue (HPMPO-DAPy) after lethal intratracheal infection of cynomolgus monkeys (Macaca fascicularis) with monkeypox virus (MPXV). MPXV causes a disease similar to human smallpox and this animal model can be used to measure differences in the protective efficacies of classical and new-generation candidate smallpox vaccines. We show that initiation of antiviral treatment 24 h after lethal intratracheal MPXV infection, using either of the antiviral agents and applying various systemic treatment regimens, resulted in significantly reduced mortality and reduced numbers of cutaneous monkeypox lesions. In contrast, when monkeys were vaccinated 24 h after MPXV infection, using a standard human dose of a currently recommended smallpox vaccine (Elstree-RIVM), no significant reduction in mortality was observed. When antiviral therapy was terminated 13 days after infection, all surviving animals had virus-specific serum antibodies and antiviral T lymphocytes. These data show that adequate preparedness for a biological threat involving smallpox should include the possibility of treating exposed individuals with antiviral compounds such as cidofovir or other selective anti-poxvirus drugs.

Complementarity-Determining Region 3 Size Spectratypes of T Cell Receptor β Chains in CD8+ T Cells following Antiviral Treatment of Chronic Hepatitis B▿

PubMed Central

Ma, Shi-Wu; Li, Yong-Yin; Zhang, Guang-Wen; Huang, Xuan; Sun, Jian; Li, Chris; Abbott, William G. H.; Hou, Jin-Lin

2011-01-01

An increased CD8+ T cell response to hepatitis B virus (HBV) peptides occurs between 12 and 24 weeks after starting antiviral therapy for chronic hepatitis B. It is not known whether these cells have antiviral function. The aim of this study was to determine whether clonal expansions of CD8+ T cells at these time points predict the virological response to therapy. Peripheral blood CD8+ T cells were obtained from 20 patients treated with lamivudine or telbivudine for chronic hepatitis B at baseline, 12 weeks, and 24 weeks. The CDR3 spectratype of each T cell receptor (TCR) β chain variable region (Vβ) gene family was analyzed, and the changes in the numbers of Vβ families with clonal expansions were compared in subjects with (n = 12) and without (n = 8) a virological response (52 week HBV DNA < 300 copies/ml). The number of CD8+ TCR Vβ families with clonal expansions at 12 weeks relative to baseline (median [10th to 90th percentile], +2.5 [0 to +7] versus +1 [0 to +2], P = 0.03) and at 24 weeks relative to 12 weeks (+1 [0 to +2] versus −1 [−3 to +4], P = 0.006) was higher in subjects with a virological response versus subjects without a virological response, as were interleukin-2 (IL-2) but not IL-21 mRNA levels in peripheral blood mononuclear cells. The duration of new expansions at 12 weeks was higher (P < 0.0001) in responders. Increased numbers of CD8+ T cell expansions after antiviral therapy are associated with a virological response to treatment. These CD8+ T cells are a potential target for a therapeutic vaccine for chronic hepatitis B. PMID:21098256

Hepatocellular carcinoma decreases the chance of successful hepatitis C virus therapy with direct-acting antivirals.

PubMed

Prenner, Stacey B; VanWagner, Lisa B; Flamm, Steven L; Salem, Riad; Lewandowski, Robert J; Kulik, Laura

2017-06-01

The approval of all-oral direct-acting antiviral (DAA) regimens for the treatment of hepatitis C virus (HCV) has led to the expansion of therapy to include patients with cirrhosis who have hepatocellular carcinoma (HCC). Data on the use of DAAs in HCV+ patients with HCC is limited. The aim of this study was to assess the efficacy of all-oral-DAA regimens in HCV+ cirrhotic patients who have or had HCC compared to those without HCC. A retrospective cohort study was conducted on all cirrhotic patients who were treated for HCV with DAAs at our institution between January 2014 and November 2015. A total of 421 HCV+ patients with cirrhosis were identified, of whom 33% had active or a history of HCC. Failure to achieve sustained virologic response (SVR) occurred in 21% of patients with HCC compared to 12% of patients without HCC (p=0.009). Of the 29 patients with HCC who did not achieve SVR, 27 (93%) occurred when an active tumor was present. DAA therapy in the presence of an inactive tumor or after removal of tumor (resection/transplant) resulted in excellent SVR rates, similar to those without HCC (p<0.0001). In multivariable analysis, the primary predictor of DAA treatment failure was the presence of active HCC at the time of HCV treatment initiation (adjusted odds ratio=8.5, 95% confidence interval=3.90-18.49). The presence of active HCC tumor at the initiation of HCV therapy is significantly associated with all-oral DAA treatment failure. HCV treatment after curative therapies for HCC resulted in excellent SVR. The new medications for hepatitis C have excellent cure rates. However, our study shows that in patients with both liver cancer and hepatitis C, they do not achieve these cure rates. Patients with liver cancer are almost 8 times more likely to fail hepatitis C treatment than patients without liver cancer. Copyright © 2017 European Association for the Study of the Liver. Published by Elsevier B.V. All rights reserved.

Use of Hematopoietic Growth Factor in the Management of Hematological Side Effects Associated to Antiviral Treatment for Hcv Hepatitis

PubMed Central

Mancino, Paola; Falasca, Katia; Ucciferri, Claudio; Pizzigallo, Eligio; Vecchiet, Jacopo

2010-01-01

Haematological abnormalities are common during combination antiviral therapy for chronic hepatitis C. Although dose reduction or discontinuation can easily treat these side effects, they can adversely affect the efficacy of combination antiviral therapy reducing the likelihood of a sustained viral response (SVR). To avoid potentially diminishing a patient’s chance of response, many physicians have begun using growth factors off-label to manage anaemia and neutropenia in hepatitis C. Haematopoietic growth factors are generally well tolerated and they may be useful for managing haematological side effects of anti-HCV therapy improving patients’ quality of life. To date, the role and benefit of these agents during anti-HCV therapy and their positive impact on SVR have not conclusively determined in the published studies. However, the possibility of a benefit to individual outpatients remains, and an individualized approach is recommended. This review explores the incidence, clinical significance, and management of anaemia, neutropenia and thrombocytopenia associated with combination therapy for HCV infection. PMID:21415945

A New Era for Cancer Target Therapies: Applying Systems Biology and Computer-Aided Drug Design to Cancer Therapies.

PubMed

Wong, Yung-Hao; Chiu, Chia-Chiun; Lin, Chih-Lung; Chen, Ting-Shou; Jheng, Bo-Ren; Lee, Yu-Ching; Chen, Jeremy; Chen, Bor-Sen

In recent years, many systems biology approaches have been used with various cancers. The materials described here can be used to build bases to discover novel cancer therapy targets in connection with computer-aided drug design (CADD). A deeper understanding of the mechanisms of cancer will provide more choices and correct strategies in the development of multiple target drug therapies, which is quite different from the traditional cancer single target therapy. Targeted therapy is one of the most powerful strategies against cancer and can also be applied to other diseases. Due to the large amount of progress in computer hardware and the theories of computational chemistry and physics, CADD has been the main strategy for developing novel drugs for cancer therapy. In contrast to traditional single target therapies, in this review we will emphasize the future direction of the field, i.e., multiple target therapies. Structure-based and ligand-based drug designs are the two main topics of CADD. The former needs both 3D protein structures and ligand structures, while the latter only needs ligand structures. Ordinarily it is estimated to take more than 14 years and 800 million dollars to develop a new drug. Many new CADD software programs and techniques have been developed in recent decades. We conclude with an example where we combined and applied systems biology and CADD to the core networks of four cancers and successfully developed a novel cocktail for drug therapy that treats multiple targets.

Choosing a therapy electron accelerator target.

PubMed

Hutcheon, R M; Schriber, S O; Funk, L W; Sherman, N K

1979-01-01

Angular distributions of photon depth dose produced by 25-MeV electrons incident on several fully stopping single-element targets (C, Al, Cu, Mo, Ta, Pb) and two composite layered targets (Ni-Al, W-Al) were studied. Depth-dose curves measured using TLD-700 (thermoluminescent dosimeter) chips embedded in lucite phantoms. Several useful therapy electron accelerator design curves were determined, including relative flattener thickness as a function of target atomic number, "effective" bremsstrahlung endpoint energy or beam "hardness" as a function of target atomic number and photon emission angle, and estimates of shielding thickness as a function of angle required to reduce the radiation outside the treatment cone to required levels.

The DNA helicase–primase complex as a target for herpes viral infection

PubMed Central

Weller, Sandra K; Kuchta, Robert D

2014-01-01

Introduction The Herpesviridae are responsible for debilitating acute and chronic infections, and some members of this family are associated with human cancers. Conventional anti-herpesviral therapy targets the viral DNA polymerase and has been extremely successful; however, the emergence of drug-resistant virus strains, especially in neonates and immunocompromised patients, underscores the need for continued development of anti-herpes drugs. In this article, we explore an alternative target for antiviral therapy, the HSV helicase/primase complex. Areas covered This review addresses the current state of knowledge of HSV DNA replication and the important roles played by the herpesvirus helicase–primase complex. In the last 10 years several helicase/primase inhibitors (HPIs) have been described, and in this article, we discuss and contrast these new agents with established inhibitors. Expert opinion The outstanding safety profile of existing nucleoside analogues for a-herpesvirus infection make the development of new therapeutic agents a challenge. Currently used nucleoside analogues exhibit few side effects and have low occurrence of clinically relevant resistance. For HCMV, however, existing drugs have significant toxicity issues and the frequency of drug resistance is high, and no antiviral therapies are available for EBV and KSHV. The development of new anti-herpesvirus drugs is thus well worth pursuing especially for immunocompromised patients and those who develop drug-resistant infections. Although the HPIs are promising, limitations to their development into a successful drug strategy remain. PMID:23930666

Prostate Cancer Clinical Consortium Clinical Research Site: Targeted Therapies

DTIC Science & Technology

2017-10-01

AWARD NUMBER: W81XWH-14-2-0159 TITLE: Prostate Cancer Clinical Consortium Clinical Research Site: Targeted Therapies PRINCIPAL INVESTIGATOR...Annual PREPARED FOR: U.S. Army Medical Research and Materiel Command Fort Detrick, Maryland 21702-5012 DISTRIBUTION STATEMENT: Approved for...AND SUBTITLE Prostate Cancer Clinical Consortium Clinical Research Site: Targeted Therapies 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT

Inhibition of CRM1-mediated nuclear export of influenza A nucleoprotein and nuclear export protein as a novel target for antiviral drug development

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chutiwitoonchai, Nopporn; Mano, Takafumi; Kakisaka

An anti-influenza compound, DP2392-E10 based on inhibition of the nuclear export function of the viral nucleoprotein-nuclear export signal 3 (NP-NES3) domain was successfully identified by our previous high-throughput screening system. Here, we demonstrated that DP2392-E10 exerts its antiviral effect by inhibiting replication of a broad range of influenza A subtypes. In regard to the molecular mechanism, we revealed that DP2392-E10 inhibits nuclear export of both viral NP and nuclear export protein (NEP). More specifically, in vitro pull-down assays revealed that DP2392-E10 directly binds cellular CRM1, which mediates nuclear export of NP and NEP. In silico docking suggested that DP2392-E10 bindsmore » at a region close to the HEAT9 and HEAT10 domains of CRM1. Together, these results indicate that the CRM1-mediated nuclear export function of influenza virus represents a new potential target for antiviral drug development, and also provide a core structure for a novel class of inhibitors that target this function. - Highlights: •DP2392-E10 inhibits replication of a broad range of influenza A subtypes. •DP2392-E10 inhibits nuclear exports of NP and NEP via their NP-NES3 and NEP-NES2 domains, respectively. •DP2392-E10 is predicted to directly bind CRM1 in the region near the HEAT9 and HEAT10 repeats.« less

Direct-Acting Antiviral Therapy for Chronic HCV Infection Results in Liver Stiffness Regression Over 12 Months Post-treatment.

PubMed

Chan, Justin; Gogela, Neliswa; Zheng, Hui; Lammert, Sara; Ajayi, Tokunbo; Fricker, Zachary; Kim, Arthur Y; Robbins, Gregory K; Chung, Raymond T

2018-02-01

Liver fibrosis stage determines risk of morbidity and mortality from chronic hepatitis C virus (HCV) infection. Prior data have shown long-term reversal of liver fibrosis, measured by vibration-controlled transient elastography (VCTE), in patients successfully treated with interferon-based therapies. Our study sought to determine the effect of treatment with modern HCV direct-acting antiviral (DAA) therapy on noninvasive liver fibrosis measurements. A total of 70 patients had VCTE-based liver stiffness measurement (LSM) taken before treatment, directly after treatment completion, and at least 12 months after completion of DAA therapy. Our primary outcome was a >30% improvement in VCTE score at the end of follow-up, relative to baseline. The sustained virologic response rate in our cohort was 95.7%. In our cohort, 34 (48.6%) met the primary outcome. Those who had baseline elevated alanine aminotransferase (OR 3.27; 95% CI 1.13-9.47) and genotype 1 (OR 14.63; 95% CI 1.70-125.83) had higher odds of meeting that outcome, and this remained significant after adjusting for age, baseline body mass index, gender, baseline elevated alkaline phosphatase levels, treatment experience, liver transplant status, smoking, and baseline liver stiffness. Treatment of chronic HCV with modern DAA therapy was associated with a significant improvement in LSM by VCTE measurement, suggesting possible early improvement in liver fibrosis along with resolution of inflammation over the first year after treatment completion.

Mental disorders in HIV/HCV coinfected patients under antiviral treatment for hepatitis C.

PubMed

Martin-Subero, Marta; Diez-Quevedo, Crisanto

2016-12-30

This paper aims to review the epidemiology and management of mental disorders in human immunodeficiency virus (HIV)/hepatitis C virus (HCV) coinfected patients, the need for antiviral therapy in this specific population, and current treatment strategies for HIV/HCV patients with psychiatric and/or substance use disorders. This is a narrative review. Data was sourced from electronic databases and was not limited by language or date of publication. HIV infection has become a survivable chronic illness. Prevalence of HCV infection among HIV-infected patients is high ranging from 50% to 90%. Patients with psychiatric diseases have also an increased risk for HIV/HCV coinfection. The most effective strategy to decrease HCV-related morbidity and mortality in coinfection is to achieve viral eradication. Although psychiatric symptoms often appear during antiviral treatment and may be associated with the use of interferon-alpha (IFN-α), recent evidence suggests that many patients with comorbid mental and substance use disorders can be treated safely. Recent data indicate that IFNα-induced psychiatric side effects have a similar prevalence in HIV/HCV coinfected patients than in monoinfected patients and they can be managed and even prevented successfully with psychopharmacological strategies in the frame of a multidisciplinary team. New antivirals offer INF-free therapies for this specific population. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Inhibition of Dengue Virus Entry into Target Cells Using Synthetic Antiviral Peptides

PubMed Central

Alhoot, Mohammed Abdelfatah; Rathinam, Alwin Kumar; Wang, Seok Mui; Manikam, Rishya; Sekaran, Shamala Devi

2013-01-01

Despite the importance of DENV as a human pathogen, there is no specific treatment or protective vaccine. Successful entry into the host cells is necessary for establishing the infection. Recently, the virus entry step has become an attractive therapeutic strategy because it represents a barrier to suppress the onset of the infection. Four putative antiviral peptides were designed to target domain III of DENV-2 E protein using BioMoDroid algorithm. Two peptides showed significant inhibition of DENV when simultaneously incubated as shown by plaque formation assay, RT-qPCR, and Western blot analysis. Both DET4 and DET2 showed significant inhibition of virus entry (84.6% and 40.6% respectively) using micromolar concentrations. Furthermore, the TEM images showed that the inhibitory peptides caused structural abnormalities and alteration of the arrangement of the viral E protein, which interferes with virus binding and entry. Inhibition of DENV entry during the initial stages of infection can potentially reduce the viremia in infected humans resulting in prevention of the progression of dengue fever to the severe life-threatening infection, reduce the infected vector numbers, and thus break the transmission cycle. Moreover these peptides though designed against the conserved region in DENV-2 would have the potential to be active against all the serotypes of dengue and might be considered as Hits to begin designing and developing of more potent analogous peptides that could constitute as promising therapeutic agents for attenuating dengue infection. PMID:23630436

Molecular targeting agents in cancer therapy: science and society.

PubMed

Shaikh, Asim Jamal

2012-01-01

The inception of targeted agents has revolutionized the cancer therapy paradigm, both for physicians and patients. A large number of molecular targeted agents for cancer therapy are currently available for clinical use today. Many more are in making, but there are issues that remain to be resolved for the scientific as well as social community before the recommendation of their widespread use in may clinical scenarios can be done, one such issue being cost and cost effectiveness, others being resistance and lack of sustained efficacy. With the current knowledge about available targeted agents, the growing knowledge of intricate molecular pathways and unfolding of wider spectrum of molecular targets that can really matter in the disease control, calls for only the just use of the agents available now, drug companies need to make a serious attempt to reduce the cost of the agents. Research should focus on agents that show sustained responses in preclinical data. More needs to be done in laboratories and by the pharmaceutical industries, before we can truly claim to have entered a new era of targeted therapy in cancer care.

Steroid-antivirals treatment versus steroids alone for the treatment of Bell's palsy: a meta-analysis.

PubMed

Dong, Yabing; Zhu, Yong; Ma, Chuan; Zhao, Huaqiang

2015-01-01

To illustrate whether the steroid-antivirals treatment could acquire a better recovery in patients with Bell's palsy than the steroids alone treatment. We conducted an exhaustive search over Pub med/Medline, Ovid, Elsevier search engines and the Cochrane library thereby collecting the randomized controlled trials in the treatment of patients with Bell's palsy with steroid-antivirals and steroids. The qualities of relevant articles were assessed by GRADE, which was used to present the overall quality of evidence as recommended by the Cochrane Handbook for Systematic Reviews of Interventions. Two investigators evaluated these papers independently, and resolved the disagreements by discussion. At last 8 eligible papers (1816 patients included: 896 treated with steroid-antivirals and 920 treated with steroids alone) match the criteria. Owing to the result (chi(2) = 12.57, P = 0.08, I(2) = 44%) presented by the formal test for heterogeneity, the fixed effect meta-analysis model was chosen. The facial muscle recovery between the steroids-antivirals group and the steroids alone group show significant differences (OR = 1.52, 95% CI: 1.20-1.94), while the statistical outcome of adverse effect shows no statistical significance (OR = 1.28, 95% CI: 0.71-2.31). The present meta-analysis indicates that the steroid-antivirals treatment could improve the recovery rate in patients with Bell's palsy when comparing with the steroid alone treatment. This meta-analysis showed that the steroid-antivirals treatment achieved the better outcomes in patients with Bell's palsy. Clinicians should consider that steroid-antivirals therapy is an alternative choice for the patients with Bell's palsy.

Molecular mechanisms for vascular complications of targeted cancer therapies.

PubMed

Gopal, Srila; Miller, Kenneth B; Jaffe, Iris Z

2016-10-01

Molecularly targeted anti-cancer therapies have revolutionized cancer treatment by improving both quality of life and survival in cancer patients. However, many of these drugs are associated with cardiovascular toxicities that are sometimes dose-limiting. Moreover, the long-term cardiovascular consequences of these drugs, some of which are used chronically, are not yet known. Although the scope and mechanisms of the cardiac toxicities are better defined, the mechanisms for vascular toxicities are only beginning to be elucidated. This review summarizes what is known about the vascular adverse events associated with three classes of novel anti-cancer therapies: vascular endothelial growth factor (VEGF) inhibitors, breakpoint cluster-Abelson (BCR-ABL) kinase inhibitors used to treat chronic myelogenous leukaemia (CML) and immunomodulatory agents (IMiDs) used in myeloma therapeutics. Three of the best described vascular toxicities are reviewed including hypertension, increased risk of acute cardiovascular ischaemic events and arteriovenous thrombosis. The available data regarding the mechanism by which each therapy causes vascular complication are summarized. When data are limited, potential mechanisms are inferred from the known effects of inhibiting each target on vascular cell function and disease. Enhanced understanding of the molecular mechanisms of vascular side effects of targeted cancer therapy is necessary to effectively manage cancer patients and to design safer targeted cancer therapies for the future. © 2016 The Author(s). published by Portland Press Limited on behalf of the Biochemical Society.

Targeting Glutamine Induces Apoptosis: A Cancer Therapy Approach

PubMed Central

Chen, Lian; Cui, Hengmin

2015-01-01

Glutamine metabolism has been proved to be dysregulated in many cancer cells, and is essential for proliferation of most cancer cells, which makes glutamine an appealing target for cancer therapy. In order to be well used by cells, glutamine must be transported to cells by specific transporters and converted to glutamate by glutaminase. There are currently several drugs that target glutaminase under development or clinical trials. Also, glutamine metabolism restriction has been proved to be effective in inhibiting tumor growth both in vivo and vitro through inducing apoptosis, growth arrest and/or autophagy. Here, we review recent researches about glutamine metabolism in cancer, and cell death induced by targeting glutamine, and their potential roles in cancer therapy. PMID:26402672

Current antiviral drugs and their analysis in biological materials - Part II: Antivirals against hepatitis and HIV viruses.

PubMed

Nováková, Lucie; Pavlík, Jakub; Chrenková, Lucia; Martinec, Ondřej; Červený, Lukáš

2018-01-05

This review is a Part II of the series aiming to provide comprehensive overview of currently used antiviral drugs and to show modern approaches to their analysis. While in the Part I antivirals against herpes viruses and antivirals against respiratory viruses were addressed, this part concerns antivirals against hepatitis viruses (B and C) and human immunodeficiency virus (HIV). Many novel antivirals against hepatitis C virus (HCV) and HIV have been introduced into the clinical practice over the last decade. The recent broadening portfolio of these groups of antivirals is reflected in increasing number of developed analytical methods required to meet the needs of clinical terrain. Part II summarizes the mechanisms of action of antivirals against hepatitis B virus (HBV), HCV, and HIV, their use in clinical practice, and analytical methods for individual classes. It also provides expert opinion on state of art in the field of bioanalysis of these drugs. Analytical methods reflect novelty of these chemical structures and use by far the most current approaches, such as simple and high-throughput sample preparation and fast separation, often by means of UHPLC-MS/MS. Proper method validation based on requirements of bioanalytical guidelines is an inherent part of the developed methods. Copyright © 2017 Elsevier B.V. All rights reserved.

Efficacy and safety of 3-week response-guided triple direct-acting antiviral therapy for chronic hepatitis C infection: a phase 2, open-label, proof-of-concept study

DOE PAGES

Lau, George; Benhamou, Yves; Chen, Guofeng; ...

2016-07-25

In order to shorten the course of direct-acting antiviral agents for chronic hepatitis C virus (HCV) infection, we examined the antiviral efficacy and safety of 3 weeks of response-guided therapy with an NS3 protease inhibitor and dual NS5A inhibitor–NS5B nucleotide analogue. In this open-label, phase 2a, single centre study, Chinese patients with chronic HCV genotype 1b infection without cirrhosis were randomly allocated by a computer program to one of three treatment groups (sofosbuvir, ledipasvir, and asunaprevir; sofosbuvir, daclatasvir, and simeprevir; or sofosbuvir, daclatasvir, and asunaprevir) until six patients in each group (1:1:1) achieved an ultrarapid virological response (plasma HCV RNAmore » <500 IU/mL by day 2, measured by COBAS TaqMan HCV test, version 2.0). Patients with an ultrarapid virological response received 3 weeks of therapy. Patients who did not achieve an ultrarapid response were switched to sofosbuvir and ledipasvir for either 8 weeks or 12 weeks. Furthermore, the primary endpoint was the proportion of patients with a sustained virological response at 12 weeks (SVR12) after treatment completion, analysed in the intention-to-treat population. All patients who achieved an ultrarapid virological response were included in the safety analysis. This trial is registered with ClinicalTrials.gov, number NCT02470858. Between April 5, 2015, and April 15, 2015, 26 eligible patients were recruited. 12 patients were assigned to sofosbuvir, ledipasvir, and asunaprevir; six to sofosbuvir, daclatasvir, and simeprevir; and eight to sofosbuvir, daclatasvir, and asunaprevir. Six patients in each group achieved an ultrarapid virological response (18 [69%]). All patients with an ultrarapid virological response who were given 3 weeks of triple therapy achieved SVR12. The most common adverse events were fatigue (one [17%] of six patients receiving sofosbuvir, ledipasvir, and asunaprevir; one [17%] of six patients receiving sofosbuvir, daclatasvir, and

Efficacy and safety of 3-week response-guided triple direct-acting antiviral therapy for chronic hepatitis C infection: a phase 2, open-label, proof-of-concept study

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lau, George; Benhamou, Yves; Chen, Guofeng

In order to shorten the course of direct-acting antiviral agents for chronic hepatitis C virus (HCV) infection, we examined the antiviral efficacy and safety of 3 weeks of response-guided therapy with an NS3 protease inhibitor and dual NS5A inhibitor–NS5B nucleotide analogue. In this open-label, phase 2a, single centre study, Chinese patients with chronic HCV genotype 1b infection without cirrhosis were randomly allocated by a computer program to one of three treatment groups (sofosbuvir, ledipasvir, and asunaprevir; sofosbuvir, daclatasvir, and simeprevir; or sofosbuvir, daclatasvir, and asunaprevir) until six patients in each group (1:1:1) achieved an ultrarapid virological response (plasma HCV RNAmore » <500 IU/mL by day 2, measured by COBAS TaqMan HCV test, version 2.0). Patients with an ultrarapid virological response received 3 weeks of therapy. Patients who did not achieve an ultrarapid response were switched to sofosbuvir and ledipasvir for either 8 weeks or 12 weeks. Furthermore, the primary endpoint was the proportion of patients with a sustained virological response at 12 weeks (SVR12) after treatment completion, analysed in the intention-to-treat population. All patients who achieved an ultrarapid virological response were included in the safety analysis. This trial is registered with ClinicalTrials.gov, number NCT02470858. Between April 5, 2015, and April 15, 2015, 26 eligible patients were recruited. 12 patients were assigned to sofosbuvir, ledipasvir, and asunaprevir; six to sofosbuvir, daclatasvir, and simeprevir; and eight to sofosbuvir, daclatasvir, and asunaprevir. Six patients in each group achieved an ultrarapid virological response (18 [69%]). All patients with an ultrarapid virological response who were given 3 weeks of triple therapy achieved SVR12. The most common adverse events were fatigue (one [17%] of six patients receiving sofosbuvir, ledipasvir, and asunaprevir; one [17%] of six patients receiving sofosbuvir, daclatasvir, and

Targeted therapies in the treatment of urothelial cancers.

PubMed

Aragon-Ching, Jeanny B; Trump, Donald L

2017-07-01

Progress has been slow in systemic management of locally advanced and metastatic bladder cancer over the past 20 years. However, the recent approval of immunotherapy with atezolizumab and nivolumab for second-line salvage therapy may usher in an era of more rapid improvement. Systemic treatment is suboptimal and is an area of substantial unmet medical need. The recent findings from The Cancer Genome Atlas project revealed promising pathways that may be amenable to targeted therapies. Promising results with treatment using vascular endothelial growth factor inhibitors such as ramucirumab, sunitinib or bevacizumab, and human epidermal growth factor receptor 2 targeted therapies, epidermal growth factor receptor inhibitors, and fibroblast growth factor receptor inhibitors, are undergoing clinical trials and are discussed later. Copyright © 2017 Elsevier Inc. All rights reserved.

Engineering a therapeutic lectin by uncoupling mitogenicity from antiviral activity.

PubMed

Swanson, Michael D; Boudreaux, Daniel M; Salmon, Loïc; Chugh, Jeetender; Winter, Harry C; Meagher, Jennifer L; André, Sabine; Murphy, Paul V; Oscarson, Stefan; Roy, René; King, Steven; Kaplan, Mark H; Goldstein, Irwin J; Tarbet, E Bart; Hurst, Brett L; Smee, Donald F; de la Fuente, Cynthia; Hoffmann, Hans-Heinrich; Xue, Yi; Rice, Charles M; Schols, Dominique; Garcia, J Victor; Stuckey, Jeanne A; Gabius, Hans-Joachim; Al-Hashimi, Hashim M; Markovitz, David M

2015-10-22

A key effector route of the Sugar Code involves lectins that exert crucial regulatory controls by targeting distinct cellular glycans. We demonstrate that a single amino-acid substitution in a banana lectin, replacing histidine 84 with a threonine, significantly reduces its mitogenicity, while preserving its broad-spectrum antiviral potency. X-ray crystallography, NMR spectroscopy, and glycocluster assays reveal that loss of mitogenicity is strongly correlated with loss of pi-pi stacking between aromatic amino acids H84 and Y83, which removes a wall separating two carbohydrate binding sites, thus diminishing multivalent interactions. On the other hand, monovalent interactions and antiviral activity are preserved by retaining other wild-type conformational features and possibly through unique contacts involving the T84 side chain. Through such fine-tuning, target selection and downstream effects of a lectin can be modulated so as to knock down one activity, while preserving another, thus providing tools for therapeutics and for understanding the Sugar Code. Copyright © 2015 Elsevier Inc. All rights reserved.

Liver stiffness predicts the response to direct-acting antiviral-based therapy against chronic hepatitis C in cirrhotic patients.

PubMed

Neukam, K; Morano-Amado, L E; Rivero-Juárez, A; Macías, J; Granados, R; Romero-Palacios, A; Márquez, M; Merino, D; Ortega, E; Alados-Arboledas, J C; Cucurull, J; Omar, M; Ryan-Murua, P; Pineda, J A

2017-05-01

The purpose of this investigation was to evaluate the impact of liver stiffness (LS) on the response to direct-acting antiviral (DAA)-based therapy against hepatitis C virus (HCV) infection in cirrhotic patients. Those patients included in two Spanish prospective cohorts of patients receiving therapy based on at least one DAA, who showed a baseline LS ≥ 12.5 kPa and who had reached the scheduled time point for sustained virological response evaluation 12 weeks after completing therapy (SVR12) were analysed. Pegylated interferon/ribavirin-based therapy plus an HCV NS3/4A protease inhibitor (PR-PI group) was administered to 198 subjects, while 146 received interferon-free regimens (IFN-free group). The numbers of patients with SVR12 according to an LS < 21 kPa versus ≥21 kPa were 59/99 (59.6%) versus 46/99 (46.5%) in the PR-PI group (p = 0.064) and 41/43 (95.3%) versus 90/103 (87.4%) in the IFN-free group (p = 0.232). Corresponding figures for the relapse rates in those who presented end-of-treatment response (ETR) were 3/62 (4.8%) versus 10/56 (17.9%, p = 0.024) and 1/42 (2.4%) versus 8/98 (8.2%, p = 0.278), respectively. In a multivariate analysis adjusted for age, sex and use of interferon, a baseline LS ≥ 21 kPa was identified as an independent predictor of relapse [adjusted odds ratio, AOR (95% confidence interval, CI): 4.228 (1.344-13.306); p = 0.014] in those patients with ETR. LS above 21 kPa is associated with higher rates of relapse to DAA-based therapy in HCV-infected patients with cirrhosis in clinical practice. LS could help us to tailor the duration and composition of DAA-based combinations in cirrhotic subjects, in order to minimise the likelihood of relapse.

Cardiotoxicity of novel HER2-targeted therapies.

PubMed

Sendur, Mehmet A N; Aksoy, Sercan; Altundag, Kadri

2013-08-01

Trastuzumab, an anti-HER2 humanized monoclonal antibody, is the standard treatment for both early and metastatic HER2-positive breast cancer. In addition to other chemotherapeutic agents, trastuzumab significantly improves response rate and survival in HER2-positive early and metastatic breast cancer. Although it is well known that trastuzumab therapy is closely associated with both symptomatic and asymptomatic cardiotoxicity, less is known about novel HER2-targeted therapies. The aim of this review is to discuss the cardiac safety data from recent studies of novel anti-HER2 drugs other than trastuzumab. Novel HER2-targeted therapies showed favorable results in HER2 positive metastatic breast cancer patients. Pubmed database, ASCO and San Antonio Breast Cancer Symposium Meeting abstracts were searched until January 2013 using the following search keywords; 'trastuzumab, trastuzumab cardiotoxicity, HER-2 targeted therapies, lapatinib, pertuzumab, trastuzumab emtansine, afatinib and neratinib'; papers which were considered relevant for the aim of this review were selected by the authors. Lapatinib, pertuzumab, T-DM1, neratinib and afatinib molecules are evaluated in the study. In a comprehensive analysis, 3689 lapatinib treated patients enrolled in 49 trials; asymptomatic cardiac events were reported in 53 patients (1.4%) and symptomatic grade III and IV systolic dysfunction was observed only in 7 patients (0.2%) treated with lapatinib. In phase I-III trials of pertuzumab, cardiac dysfunction was seen in 4.5-14.5% of patients with pertuzumab treatment and cardiac dysfunction was usually grade I and II. Cardiotoxicity of pertuzumab was usually reported with the trastuzumab combination and no additive cardiotoxicity was reported with addition of pertuzumab to trastuzumab. T-DM1 had a better safety profile compared to trastuzumab, no significant cardiotoxicity was observed with T-DM1 in heavily pre-treated patients. In the EMILIA study, only in 1.7% of patients in the T

Antiviral RNA silencing suppression activity of Tomato spotted wilt virus NSs protein.

PubMed

Ocampo Ocampo, T; Gabriel Peralta, S M; Bacheller, N; Uiterwaal, S; Knapp, A; Hennen, A; Ochoa-Martinez, D L; Garcia-Ruiz, H

2016-06-17

In addition to regulating gene expression, RNA silencing is an essential antiviral defense system in plants. Triggered by double-stranded RNA, silencing results in degradation or translational repression of target transcripts. Viruses are inducers and targets of RNA silencing. To condition susceptibility, most plant viruses encode silencing suppressors that interfere with this process, such as the Tomato spotted wilt virus (TSWV) NSs protein. The mechanism by which NSs suppresses RNA silencing and its role in viral infection and movement remain to be determined. We cloned NSs from the Hawaii isolate of TSWV and using two independent assays show for the first time that this protein restored pathogenicity and supported the formation of local infection foci by suppressor-deficient Turnip mosaic virus and Turnip crinkle virus. Demonstrating the suppression of RNA silencing directed against heterologous viruses establishes the foundation to determine the means used by NSs to block this antiviral process.

Enhancing the antiviral potency of ER α-glucosidase inhibitor IHVR-19029 against hemorrhagic fever viruses in vitro and in vivo.

PubMed

Ma, Julia; Zhang, Xuexiang; Soloveva, Veronica; Warren, Travis; Guo, Fang; Wu, Shuo; Lu, Huagang; Guo, Jia; Su, Qing; Shen, Helen; Solon, Eric; Comunale, Mary Ann; Mehta, Anand; Guo, Ju-Tao; Bavari, Sina; Du, Yanming; Block, Timothy M; Chang, Jinhong

2018-02-01

Targeting host functions essential for viral replication has been considered as a broad spectrum and resistance-refractory antiviral approach. However, only a few host functions have, thus far, been validated as broad-spectrum antiviral targets in vivo. ER α-glucosidases I and II have been demonstrated to be essential for the morphogenesis of many enveloped viruses, including members from four families of viruses causing hemorrhagic fever. In vivo antiviral efficacy of various iminosugar-based ER α-glucosidase inhibitors has been reported in animals infected with Dengue, Japanese encephalitis, Ebola, Marburg and influenza viruses. Herein, we established Huh7.5-derived cell lines with ER α-glucosidase I or II knockout using CRISPR/Cas9 and demonstrated that the replication of Dengue, Yellow fever and Zika viruses was reduced by only 1-2 logs in the knockout cell lines. The results clearly indicate that only a partial suppression of viral replication can possibly be achieved with a complete inhibition of ER-α-glucosidases I or II by their inhibitors. We therefore explore to improve the antiviral efficacy of a lead iminosugar IHVR-19029 through combination with another broad-spectrum antiviral agent, favipiravir (T-705). Indeed, combination of IHVR-19029 and T-705 synergistically inhibited the replication of Yellow fever and Ebola viruses in cultured cells. Moreover, in a mouse model of Ebola virus infection, combination of sub-optimal doses of IHVR-19029 and T-705 significantly increased the survival rate of infected animals. We have thus proved the concept of combinational therapeutic strategy for the treatment of viral hemorrhagic fevers with broad spectrum host- and viral- targeting antiviral agents. Copyright © 2017 Elsevier B.V. All rights reserved.

Antiviral Peptides Targeting the West Nile Virus Envelope Protein▿

PubMed Central

Bai, Fengwei; Town, Terrence; Pradhan, Deepti; Cox, Jonathan; Ashish; Ledizet, Michel; Anderson, John F.; Flavell, Richard A.; Krueger, Joanna K.; Koski, Raymond A.; Fikrig, Erol

2007-01-01

West Nile virus (WNV) can cause fatal murine and human encephalitis. The viral envelope protein interacts with host cells. A murine brain cDNA phage display library was therefore probed with WNV envelope protein, resulting in the identification of several adherent peptides. Of these, peptide 1 prevented WNV infection in vitro with a 50% inhibition concentration of 67 μM and also inhibited infection of a related flavivirus, dengue virus. Peptide 9, a derivative of peptide 1, was a particularly potent inhibitor of WNV in vitro, with a 50% inhibition concentration of 2.6 μM. Moreover, mice challenged with WNV that had been incubated with peptide 9 had reduced viremia and fatality compared with control animals. Peptide 9 penetrated the murine blood-brain barrier and was found in the brain parenchyma, implying that it may have antiviral activity in the central nervous system. These short peptides serve as the basis for developing new therapeutics for West Nile encephalitis and, potentially, other flaviviruses. PMID:17151121

Cancer therapies in HIV cure research.

PubMed

Rasmussen, Thomas A; Anderson, Jenny L; Wightman, Fiona; Lewin, Sharon R

2017-01-01

This article provides an overview of anticancer therapies in various stages of clinical development as potential interventions to target HIV persistence. Epigenetic drugs developed for cancer have been investigated in vitro, ex vivo and in clinical trials as interventions aimed at reversing HIV latency and depleting the amount of virus that persists on antiretroviral therapy. Treatment with histone deacetylase inhibitors induced HIV expression in patients on antiretroviral therapy but did not reduce the frequency of infected cells. Other interventions that may accelerate the decay of latently infected cells, in the presence or absence of latency-reversing therapy, are now being explored. These include apoptosis-promoting agents, nonhistone deacetylase inhibitor compounds to reverse HIV latency and immunotherapy interventions to enhance antiviral immunity such as immune checkpoint inhibitors and Toll-like receptor agonists. A curative strategy in HIV will likely need to both reduce the amount of virus that persists on antiretroviral therapy and improve anti-HIV immune surveillance. Although we continue to explore advances in the field of oncology including cancer immunotherapy, there are major differences in the risk-benefit assessment between HIV-infected individuals and patients with malignancies. Drug development specifically targeting HIV persistence will be the key to developing effective interventions with an appropriate safety profile.

Delivering direct acting antiviral therapy for hepatitis C to highly marginalised and current drug injecting populations in a targeted primary health care setting.

PubMed

Read, Phillip; Lothian, Rebecca; Chronister, Karen; Gilliver, Rosie; Kearley, John; Dore, Gregory J; van Beek, Ingrid

2017-09-01

The Kirketon Road Centre (KRC) is a community-based public health facility in Sydney, Australia, that provides healthcare to people who inject drugs (PWID), including hepatitis C virus (HCV) treatment. From March 2016, the Australian Government has provided access to direct-acting antivirals (DAA) for adults with chronic HCV, without liver disease stage or drug and alcohol use restrictions. The aim of this study was to report DAA treatment outcomes among highly marginalised PWID treated at KRC. All individuals initiating DAA treatment at KRC and due for sustained virological response (SVR12) testing by end 2016 were included. Demographic, drug use behaviour, clinical parameters, adherence support and HCV treatment outcomes, including SVR12 were recorded. Factors associated with SVR12, loss-to-follow-up (LTFU) and delayed SVR12 testing (>SVR16) were assessed by multivariate analysis. SVR12 was assessed by intention-to-treat (ITT) and modified ITT, the latter excluding individuals with an end-of-treatment response (ETR) but no SVR12 assessment, or who postponed their SVR12 date due to treatment interruption. A total of 72 individuals commencing DAAs were included, of whom 67% were male, 30% homeless, and 32% Aboriginal. All had a lifetime history of injecting drug use, with 75% having injected within the last six months, and 44% injecting at least weekly; 25% were also enrolled in opioid substitution therapy. Twenty-five (35%) individuals elected to receive an enhanced adherence-support package. Fifty-nine of 72 (82%) individuals due for SVR12 attended for testing, of whom 59/59 (100%) achieved SVR, providing an ITT SVR of 82%. A further six individuals had undetectable HCV RNA at ETR, but no SVR12 assessment, and one interrupted treatment, providing a mITT SVR of 91%. Homelessness was associated with delayed SVR12 testing (OR 24.9 95%CI 2.9-212.8, p=0.003). There was no association between LTFU and frequency of drug injection, last drug injected, or planned

Gene Therapy Targeting Glaucoma: Where Are We?

PubMed Central

Liu, Xuyang; Rasmussen, Carol A.; Gabelt, B’Ann T.; Brandt, Curtis R.; Kaufman, Paul L.

2010-01-01

In a chronic disease such as glaucoma, a therapy that provides a long lasting local effect, with minimal systemic side effects, while circumventing the issue of patient compliance, is very attractive. The field of gene therapy is growing rapidly and ocular applications are expanding. Our understanding of the molecular pathogenesis of glaucoma is leading to greater specificity in ocular tissue targeting. Improvements in gene delivery techniques, refinement of vector construction methods, and development of better animal models combine to bring this potential therapy closer to reality. PMID:19539835

Flaviviral NS4b, chameleon and jack‐in‐the‐box roles in viral replication and pathogenesis, and a molecular target for antiviral intervention

PubMed Central

Zmurko, Joanna; Dallmeier, Kai

2015-01-01

Summary Dengue virus and other flaviviruses such as the yellow fever, West Nile, and Japanese encephalitis viruses are emerging vector‐borne human pathogens that affect annually more than 100 million individuals and that may cause debilitating and potentially fatal hemorrhagic and encephalitic diseases. Currently, there are no specific antiviral drugs for the treatment of flavivirus‐associated disease. A better understanding of the flavivirus–host interactions during the different events of the flaviviral life cycle may be essential when developing novel antiviral strategies. The flaviviral non‐structural protein 4b (NS4b) appears to play an important role in flaviviral replication by facilitating the formation of the viral replication complexes and in counteracting innate immune responses such as the following: (i) type I IFN signaling; (ii) RNA interference; (iii) formation of stress granules; and (iv) the unfolded protein response. Intriguingly, NS4b has recently been shown to constitute an excellent target for the selective inhibition of flavivirus replication. We here review the current knowledge on NS4b. © 2015 The Authors. Reviews in Medical Virology published by John Wiley & Sons Ltd. PMID:25828437

Cross Talk between PML and p53 during Poliovirus Infection: Implications for Antiviral Defense

PubMed Central

Pampin, Mathieu; Simonin, Yannick; Blondel, Bruno; Percherancier, Yann; Chelbi-Alix, Mounira K.

2006-01-01

PML nuclear bodies (NBs) are dynamic intranuclear structures harboring numerous transiently or permanently localized proteins. PML, the NBs' organizer, is directly induced by interferon, and its expression is critical for antiviral host defense. We describe herein the molecular events following poliovirus infection that lead to PML-dependent p53 activation and protection against virus infection. Poliovirus infection induces PML phosphorylation through the extracellular signal-regulated kinase pathway, increases PML SUMOylation, and induces its transfer from the nucleoplasm to the nuclear matrix. These events result in the recruitment of p53 to PML NBs, p53 phosphorylation on Ser15, and activation of p53 target genes leading to the induction of apoptosis. Moreover, the knock-down of p53 by small interfering RNA results in higher poliovirus replication, suggesting that p53 participates in antiviral defense. This effect, which requires the presence of PML, is transient since poliovirus targets p53 by inducing its degradation in a proteasome- and MDM2-dependent manner. Our results provide evidence of how poliovirus counteracts p53 antiviral activity by regulating PML and NBs, thus leading to p53 degradation. PMID:16912307

Cross talk between PML and p53 during poliovirus infection: implications for antiviral defense.

PubMed

Pampin, Mathieu; Simonin, Yannick; Blondel, Bruno; Percherancier, Yann; Chelbi-Alix, Mounira K

2006-09-01

PML nuclear bodies (NBs) are dynamic intranuclear structures harboring numerous transiently or permanently localized proteins. PML, the NBs' organizer, is directly induced by interferon, and its expression is critical for antiviral host defense. We describe herein the molecular events following poliovirus infection that lead to PML-dependent p53 activation and protection against virus infection. Poliovirus infection induces PML phosphorylation through the extracellular signal-regulated kinase pathway, increases PML SUMOylation, and induces its transfer from the nucleoplasm to the nuclear matrix. These events result in the recruitment of p53 to PML NBs, p53 phosphorylation on Ser15, and activation of p53 target genes leading to the induction of apoptosis. Moreover, the knock-down of p53 by small interfering RNA results in higher poliovirus replication, suggesting that p53 participates in antiviral defense. This effect, which requires the presence of PML, is transient since poliovirus targets p53 by inducing its degradation in a proteasome- and MDM2-dependent manner. Our results provide evidence of how poliovirus counteracts p53 antiviral activity by regulating PML and NBs, thus leading to p53 degradation.

Alisporivir Has Limited Antiviral Effects Against Ebola Virus Strains Makona and Mayinga.

PubMed

Chiramel, Abhilash I; Banadyga, Logan; Dougherty, Jonathan D; Falzarano, Darryl; Martellaro, Cynthia; Brees, Dominique; Taylor, R Travis; Ebihara, Hideki; Best, Sonja M

2016-10-15

Antiviral therapeutics with existing clinical safety profiles would be highly desirable in an outbreak situation, such as the 2013-2016 emergence of Ebola virus (EBOV) in West Africa. Although, the World Health Organization declared the end of the outbreak early 2016, sporadic cases of EBOV infection have since been reported. Alisporivir is the most clinically advanced broad-spectrum antiviral that functions by targeting a host protein, cyclophilin A (CypA). A modest antiviral effect of alisporivir against contemporary (Makona) but not historical (Mayinga) EBOV strains was observed in tissue culture. However, this effect was not comparable to observations for an alisporivir-susceptible virus, the flavivirus tick-borne encephalitis virus. Thus, EBOV does not depend on (CypA) for replication, in contrast to many other viruses pathogenic to humans. Published by Oxford University Press for the Infectious Diseases Society of America 2016. This work is written by (a) US Government employee(s) and is in the public domain in the US.

Oral antiviral therapy for prevention of genital herpes outbreaks in immunocompetent and nonpregnant patients.

PubMed

Le Cleach, Laurence; Trinquart, Ludovic; Do, Giao; Maruani, Annabel; Lebrun-Vignes, Benedicte; Ravaud, Philippe; Chosidow, Olivier

2014-08-03

acyclovir; pooled RR 1.04, 95% CI, 0.71 to 1.49 for famciclovir vs acyclovir; and pooled RR 1.26, 95% CI 0.89 to 1.75 for famciclovir vs valacyclovir). Safety data were sought but were reported as total numbers of adverse events. Owing to risk of bias and inconsistency, there is low quality evidence that suppressive antiviral therapy with acyclovir, valacyclovir or famciclovir in pacients experiencing at least four recurrences of genital herpes per year decreases the number of pacients with at least one recurrence as compared with placebo. Network meta-analysis of the few direct comparisons and the indirect comparisons did not show superiority of one drug over another.

Management of pulmonary toxicity associated with targeted anticancer therapies.

PubMed

Teuwen, Laure-Anne; Van den Mooter, Tom; Dirix, Luc

2015-01-01

Targeted anticancer therapies act by interfering with defined molecular entities and/or biologic pathways. Because of their more specific mechanism of action, adverse events (AEs) on healthy tissues are intended to be minimal, resulting in a different toxicity profile from that observed with conventional cytotoxic chemotherapy. Pulmonary AEs are rare but potentially life-threatening and it is, therefore, critical to recognize early on and manage appropriately. In this review, we aim to offer an overview of both more frequent and rare pulmonary AEs caused by targeted anticancer therapies and discuss possible treatment algorithms. Anti-vascular endothelial growth factor, anti-human epidermal growth factor receptor and anti-CD20 therapy will be reviewed, as well as immune checkpoint inhibitors, anaplastic lymphoma kinase inhibitors and mammalian target of rapamycin inhibitors. Novel agents used in the treatment of cancer have specific side-effects, the result of allergic reactions, on-target and off-target effects. Clinical syndromes associated with pulmonary toxicity vary from bronchospasms, hypersensitivity reactions, pneumonitis, acute respiratory distress, lung bleeding, pleural effusion to pneumothorax. Knowledge of risk factors, a high index of suspicion and a complete diagnostic work-up are essential for limiting the risk of these events becoming life threatening. The development of treatment algorithms is extremely helpful in managing these events. It is probable that these toxicities will be even more frequent with the introduction of combination therapies with the obvious challenge of discerning the responsible agent.

Targeted therapy according to next generation sequencing-based panel sequencing.

PubMed

Saito, Motonobu; Momma, Tomoyuki; Kono, Koji

2018-04-17

Targeted therapy against actionable gene mutations shows a significantly higher response rate as well as longer survival compared to conventional chemotherapy, and has become a standard therapy for many cancers. Recent progress in next-generation sequencing (NGS) has enabled to identify huge number of genetic aberrations. Based on sequencing results, patients recommend to undergo targeted therapy or immunotherapy. In cases where there are no available approved drugs for the genetic mutations detected in the patients, it is recommended to be facilitate the registration for the clinical trials. For that purpose, a NGS-based sequencing panel that can simultaneously target multiple genes in a single investigation has been used in daily clinical practice. To date, various types of sequencing panels have been developed to investigate genetic aberrations with tumor somatic genome variants (gain-of-function or loss-of-function mutations, high-level copy number alterations, and gene fusions) through comprehensive bioinformatics. Because sequencing panels are efficient and cost-effective, they are quickly being adopted outside the lab, in hospitals and clinics, in order to identify personal targeted therapy for individual cancer patients.

New PARP targets for cancer therapy

PubMed Central

Vyas, Sejal; Chang, Paul

2015-01-01

Poly(ADP-ribose) polymerases (PARPs) modify target proteins post-translationally with poly(ADP-ribose) (PAR) or mono(ADP-ribose) (MAR) using NAD+ as substrate. The best-studied PARPs generate PAR modifications and include PARP1 and the tankyrase PARP5a, both of which are targets for cancer therapy with inhibitors in either clinical trials or preclinical development. There are 15 additional PARPs, the majority of which modify proteins with MAR, and their biology is less well understood. Recent data identify potentially cancer relevant functions for these PARPs, indicating that we need to understand more about these PARPs in order to target them effectively. PMID:24898058

Antiviral therapy in cytomegalovirus-positive ulcerative colitis: A systematic review and meta-analysis

PubMed Central

Kopylov, Uri; Eliakim-Raz, Noa; Szilagy, Andrew; Seidman, Ernest; Ben-Horin, Shomron; Katz, Lior

2014-01-01

AIM: To evaluate the impact of antiviral treatment on cytomegalovirus (CMV)-positive ulcerative colitis patients. METHODS: We performed a systematic review and meta-analysis (MA) of comparative cohort and case-control studies published between January 1966 and March 2013. Studies focusing on colectomy series and studies including only less than 3 patients in the treated or non-treated arm were excluded. The primary outcome was colectomy within 30 d of diagnosis. Secondary outcomes included colectomy during the follow-up period Subgroup analyses by method of detection of CMV, study design, risk of bias and country of origin were performed. Quality of studies was evaluated according to modified New-Castle Ottawa Scale. RESULTS: After full-text review, nine studies with a total of 176 patients were included in our MA. All the included studies were of low to moderate quality. Patients who have received antiviral treatment had a higher risk of 30-d colectomy (OR = 2.40; 95%CI: 1.05-5.50; I2 = 37.2%). A subgroup analysis including only patients in whom CMV diagnosis was based did not demonstrate a significant difference between the groups (OR = 3.41; 95%CI: 0.39-29.83; I2 = 56.9%). Analysis of long-term colectomy rates was possible for 6 studies including 110 patients. No statistically significant difference was found between the treated and untreated groups (OR = 1.71; 95%CI: 0.71-4.13; 6 studies, I2 = 0%). Analysis of mortality rate was not possible due to a very limited number of cases. Stratification of the outcomes by disease severity was not possible. CONCLUSION: No positive association between antiviral treatment and a favorable outcome was demonstrated. These findings should be interpreted cautiously due to primary studies’ quality and potential biases. PMID:24627606

Antiviral therapy in cytomegalovirus-positive ulcerative colitis: a systematic review and meta-analysis.

PubMed

Kopylov, Uri; Eliakim-Raz, Noa; Szilagy, Andrew; Seidman, Ernest; Ben-Horin, Shomron; Katz, Lior

2014-03-14

To evaluate the impact of antiviral treatment on cytomegalovirus (CMV)-positive ulcerative colitis patients. We performed a systematic review and meta-analysis (MA) of comparative cohort and case-control studies published between January 1966 and March 2013. Studies focusing on colectomy series and studies including only less than 3 patients in the treated or non-treated arm were excluded. The primary outcome was colectomy within 30 d of diagnosis. Secondary outcomes included colectomy during the follow-up period Subgroup analyses by method of detection of CMV, study design, risk of bias and country of origin were performed. Quality of studies was evaluated according to modified New-Castle Ottawa Scale. After full-text review, nine studies with a total of 176 patients were included in our MA. All the included studies were of low to moderate quality. Patients who have received antiviral treatment had a higher risk of 30-d colectomy (OR = 2.40; 95%CI: 1.05-5.50; I² = 37.2%). A subgroup analysis including only patients in whom CMV diagnosis was based did not demonstrate a significant difference between the groups (OR = 3.41; 95%CI: 0.39-29.83; I² = 56.9%). Analysis of long-term colectomy rates was possible for 6 studies including 110 patients. No statistically significant difference was found between the treated and untreated groups (OR = 1.71; 95%CI: 0.71-4.13; 6 studies, I² = 0%). Analysis of mortality rate was not possible due to a very limited number of cases. Stratification of the outcomes by disease severity was not possible. No positive association between antiviral treatment and a favorable outcome was demonstrated. These findings should be interpreted cautiously due to primary studies' quality and potential biases.

Two pore channels control Ebolavirus host cell entry and are drug targets for disease treatment

PubMed Central

Sakurai, Yasuteru; Kolokoltsov, Andrey A.; Chen, Cheng-Chang; Tidwell, Michael W.; Bauta, William E.; Klugbauer, Norbert; Grimm, Christian; Wahl-Schott, Christian; Biel, Martin; Davey, Robert A.

2015-01-01

Ebolavirus causes sporadic outbreaks of lethal hemorrhagic fever in humans with no currently approved therapy. Cells take up Ebolavirus by macropinocytosis, followed by trafficking through endosomal vesicles. However, few factors controlling endosomal virus movement are known. Here we find that Ebolavirus entry into host cells requires the endosomal calcium channels called two pore channels (TPCs). Disrupting TPC function by gene knockout, small interfering RNAs or small molecule inhibitors halted virus trafficking and prevented infection. Tetrandrine, the most potent small molecule we tested, inhibited infection of human macrophages, the primary target of Ebolavirus in vivo, and also showed therapeutic efficacy in mice. Therefore, TPC proteins play a key role in Ebolavirus infection and may be effective targets for antiviral therapy. PMID:25722412

Enhancing Targeted Therapy for Myeloproliferative Neoplasms

DTIC Science & Technology

2013-10-01

Myeloproliferative Neoplasms PRINCIPAL INVESTIGATOR: Gary W. Reuther CONTRACTING...2. REPORT TYPE Annual 3. DATES COVERED 30 2012-2 2013 4. TITLE AND SUBTITLE Enhancing Targeted Therapy for Myeloproliferative Neoplasms ...AVAILABILITY STATEMENT Approved for Public Release; Distribution Unlimited 13. SUPPLEMENTARY NOTES 14. ABSTRACT Myeloproliferative neoplasms

Use of HCV+ Donors Does Not Affect HCV Clearance With Directly Acting Antiviral Therapy But Shortens the Wait Time to Kidney Transplantation.

PubMed

Sawinski, Deirdre; Patel, Nikunjkumar; Appolo, Brenda; Bloom, Roy

2017-05-01

Hepatitis C virus (HCV) infection is prevalent in the renal transplant population but direct acting antiviral agents (DAA) provide an effective cure of HCV infection without risk of allograft rejection. We report our experience treating 43 renal transplant recipients with 4 different DAA regimens. One hundred percent achieved a sustained viral response by 12 weeks after therapy, and DAA regimens were well tolerated. Recipients transplanted with a HCV+ donor responded equally well to DAA therapy those transplanted with a kidney from an HCV- donor, but recipients of HCV+ organs experienced significantly shorter wait times to transplantation, 485 days (interquartile range, 228-783) versus 969 days (interquartile range, 452-2008; P = 0.02). On this basis, we advocate for a strategy of early posttransplant HCV eradication to facilitate use of HCV+ organs whenever possible. Additional studies are needed to identify the optimal DAA regimen for kidney transplant recipients, accounting for efficacy, timing relative to transplant, posttransplant clinical outcomes, and cost.

Discovery of a Broad-Spectrum Antiviral Compound That Inhibits Pyrimidine Biosynthesis and Establishes a Type 1 Interferon-Independent Antiviral State

PubMed Central

Adcock, Robert S.; Schroeder, Chad E.; Chu, Yong-Kyu; Sotsky, Julie B.; Cramer, Daniel E.; Chilton, Paula M.; Song, Chisu; Anantpadma, Manu; Davey, Robert A.; Prodhan, Aminul I.; Yin, Xinmin; Zhang, Xiang

2016-01-01

Viral emergence and reemergence underscore the importance of developing efficacious, broad-spectrum antivirals. Here, we report the discovery of tetrahydrobenzothiazole-based compound 1, a novel, broad-spectrum antiviral lead that was optimized from a hit compound derived from a cytopathic effect (CPE)-based antiviral screen using Venezuelan equine encephalitis virus. Compound 1 showed antiviral activity against a broad range of RNA viruses, including alphaviruses, flaviviruses, influenza virus, and ebolavirus. Mechanism-of-action studies with metabolomics and molecular approaches revealed that the compound inhibits host pyrimidine synthesis and establishes an antiviral state by inducing a variety of interferon-stimulated genes (ISGs). Notably, the induction of the ISGs by compound 1 was independent of the production of type 1 interferons. The antiviral activity of compound 1 was cell type dependent with a robust effect observed in human cell lines and no observed antiviral effect in mouse cell lines. Herein, we disclose tetrahydrobenzothiazole compound 1 as a novel lead for the development of a broad-spectrum, antiviral therapeutic and as a molecular probe to study the mechanism of the induction of ISGs that are independent of type 1 interferons. PMID:27185801

Familial breast cancer - targeted therapy in secondary and tertiary prevention.

PubMed

Kast, Karin; Rhiem, Kerstin

2015-02-01

The introduction of an increasing number of individualized molecular targeted therapies into clinical routine mirrors their importance in modern cancer prevention and treatment. Well-known examples for targeted agents are the monoclonal antibody trastuzumab and the selective estrogen receptor modulator tamoxifen. The identification of an unaltered gene in tumor tissue in colon cancer (KRAS) is a predictor for the patient's response to targeted therapy with a monoclonal antibody (cetuximab). Targeted therapy for hereditary breast and ovarian cancer has become a reality with the approval of olaparib for platin-sensitive late relapsed BRCA-associated ovarian cancer in December 2014. This manuscript reviews the status quo of poly-ADP-ribose polymerase inhibitors (PARPi) in the therapy of breast and ovarian cancer as well as the struggle for carboplatin as a potential standard of care for triple-negative and, in particular, BRCA-associated breast cancer. Details of the mechanism of action with information on tumor development are provided, and an outlook for further relevant research is given. The efficacy of agents against molecular targets together with the identification of an increasing number of cancer-associated genes will open the floodgates to a new era of treatment decision-making based on molecular tumor profiles. Current clinical trials involving patients with BRCA-associated cancer explore the efficacy of the molecular targeted therapeutics platinum and PARPi.

Drug-Drug Interaction between the Direct-Acting Antiviral Regimen of Ombitasvir-Paritaprevir-Ritonavir plus Dasabuvir and the HIV Antiretroviral Agent Dolutegravir or Abacavir plus Lamivudine.

PubMed

Khatri, Amit; Trinh, Roger; Zhao, Weihan; Podsadecki, Thomas; Menon, Rajeev

2016-10-01

The direct-acting antiviral regimen of 25 mg ombitasvir-150 mg paritaprevir-100 mg ritonavir once daily (QD) plus 250 mg dasabuvir twice daily (BID) is approved for the treatment of hepatitis C virus genotype 1 infection, including patients coinfected with human immunodeficiency virus. This study was performed to evaluate the pharmacokinetic, safety, and tolerability effects of coadministering the regimen of 3 direct-acting antivirals with two antiretroviral therapies (dolutegravir or abacavir plus lamivudine). Healthy volunteers (n = 24) enrolled in this phase I, single-center, open-label, multiple-dose study received 50 mg dolutegravir QD for 7 days or 300 mg abacavir plus 300 mg lamivudine QD for 4 days, the 3-direct-acting-antiviral regimen for 14 days, followed by the 3-direct-acting-antiviral regimen with dolutegravir or abacavir plus lamivudine for 10 days. Pharmacokinetic parameters were calculated to compare combination therapy with 3-direct-acting-antiviral or antiretroviral therapy alone, and safety/tolerability were assessed throughout the study. Coadministration of the 3-direct-acting-antiviral regimen increased the geometric mean maximum plasma concentration (Cmax) and the area under the curve (AUC) of dolutegravir by 22% (central value ratio [90% confidence intervals], 1.219 [1.153, 1.288]) and 38% (1.380 [1.295, 1.469]), respectively. Abacavir geometric mean Cmax and AUC values decreased by 13% (0.873 [0.777, 0.979]) and 6% (0.943 [0.901, 0.986]), while those for lamivudine decreased by 22% (0.778 [0.719, 0.842]) and 12% (0.876 [0.821, 0.934]). For the 3-direct-acting-antiviral regimen, geometric mean Cmax and AUC during coadministration were within 18% of measurements made during administration of the 3-direct-acting-antiviral regimen alone, although trough concentrations for paritaprevir were 34% (0.664 [0.585, 0.754]) and 27% (0.729 [0.627, 0.847]) lower with dolutegravir and abacavir-lamivudine, respectively. All study treatments were generally

Targeted and Nontargeted α-Particle Therapies.

PubMed

McDevitt, Michael R; Sgouros, George; Sofou, Stavroula

2018-06-04

α-Particle irradiation of cancerous tissue is increasingly recognized as a potent therapeutic option. We briefly review the physics, radiobiology, and dosimetry of α-particle emitters, as well as the distinguishing features that make them unique for radiopharmaceutical therapy. We also review the emerging clinical role of α-particle therapy in managing cancer and recent studies on in vitro and preclinical α-particle therapy delivered by antibodies, other small molecules, and nanometer-sized particles. In addition to their unique radiopharmaceutical characteristics, the increased availability and improved radiochemistry of α-particle radionuclides have contributed to the growing recent interest in α-particle radiotherapy. Targeted therapy strategies have presented novel possibilities for the use of α-particles in the treatment of cancer. Clinical experience has already demonstrated the safe and effective use of α-particle emitters as potent tumor-selective drugs for the treatment of leukemia and metastatic disease.

Targeted and Nontargeted α-Particle Therapies

PubMed Central

McDevitt, Michael R.; Sgouros, George; Sofou, Stavroula

2018-01-01

α-Particle irradiation of cancerous tissue is increasingly recognized as a potent therapeutic option. We briefly review the physics, radiobiology, and dosimetry of α-particle emitters, as well as the distinguishing features that make them unique for radiopharmaceutical therapy. We also review the emerging clinical role of α-particle therapy in managing cancer and recent studies on in vitro and preclinical α-particle therapy delivered by antibodies, other small molecules, and nanometer-sized particles. In addition to their unique radiopharmaceutical characteristics, the increased availability and improved radiochemistry of α-particle radionuclides have contributed to the growing recent interest in α-particle radiotherapy. Targeted therapy strategies have presented novel possibilities for the use of α-particles in the treatment of cancer. Clinical experience has already demonstrated the safe and effective use of α-particle emitters as potent tumor-selective drugs for the treatment of leukemia and metastatic disease. PMID:29345977

Hepatoma targeting peptide conjugated bio-reducible polymer complexed with oncolytic adenovirus for cancer gene therapy

PubMed Central

Choi, Joung-Woo; Kim, Hyun Ah; Nam, Kihoon; Na, Youjin; Yun, Chae-Ok; Kim, SungWan

2015-01-01

Despite adenovirus (Ad) vector’s numerous advantages for cancer gene therapy, such as high ability of endosomal escape, efficient nuclear entry mechanism, and high transduction, and therapeutic efficacy, tumor specific targeting and antiviral immune response still remain as a critical challenge in clinical setting. To overcome these obstacles and achieve cancer-specific targeting, we constructed tumor targeting bioreducible polymer, an arginine grafted bio-reducible polymer (ABP)-PEG-HCBP1, by conjugating PEGylated ABP with HCBP1 peptides which has high affinity and selectivity towards hepatoma. The ABP-PEG-HCBP1-conjugated replication incompetent GFP-expressing ad, (Ad/GFP)-ABP-PEG-HCBP1, showed a hepatoma cancer specific uptake and transduction compared to either naked Ad/GFP or Ad/GFP-ABP. Competition assays demonstrated that Ad/GFP-ABP-PEG-HCBP1-mediated transduction was specifically inhibited by HCBP1 peptide rather than coxsackie and adenovirus receptor specific antibody. In addition, ABP-PEG-HCBP1 can protect biological activity of Ad against serum, and considerably reduced both innate and adaptive immune response against Ad. shMet-expressing oncolytic Ad (oAd; RdB/shMet) complexed with ABP-PEG-HCBP1 delivered oAd efficiently into hepatoma cancer cells. The oAd/ABP-PEG-HCBP1 demonstrated enhanced cancer cell killing efficacy in comparison to oAd/ABP complex. Furthermore, Huh7 and HT1080 cancer cells treated with oAd/shMet-ABP-PEG-HCBP1 complex had significantly decreased Met and VEGF expression in hepatoma cancer, but not in non-hepatoma cancer. In sum, these results suggest that HCBP1-conjugated bioreducible polymer could be used to deliver oncolytic Ad safely and efficiently to treat hepatoma. PMID:26437261

Amino acid substitutions in the hepatitis C virus core region predict hepatocarcinogenesis following eradication of HCV RNA by all-oral direct-acting antiviral regimens.

PubMed

Ogata, Fumihiro; Akuta, Norio; Kobayashi, Masahiro; Fujiyama, Shunichiro; Kawamura, Yusuke; Sezaki, Hitomi; Hosaka, Tetsuya; Kobayashi, Mariko; Saitoh, Satoshi; Suzuki, Yoshiyuki; Suzuki, Fumitaka; Arase, Yasuji; Ikeda, Kenji; Kumada, Hiromitsu

2018-06-01

Impact of substitution of aa70 in the core region (Core aa70) in HCV genotype 1b (HCV-1b) on hepatocarcinogenesis following eradication of HCV RNA by direct-acting antiviral therapy is not clear. In a retrospective study, 533 patients with HCV-related chronic liver disease, with sustained virological response defined as negative HCV RNA at 12 weeks after cessation of direct-acting antiviral therapy, were examined to evaluate the relationship between Core aa70 substitution and hepatocarcinogenesis. Twelve patients developed hepatocellular carcinoma during the follow-up period. The cumulative hepatocarcinogenesis rates were 1.7% and 2.4% at the end of 1 and 2 years, respectively. Overall, multivariate analysis identified HCV subgroup (HCV-1b with Gln70(His70); P = 0.003) and age (>65 years; P = 0.049), as pretreatment predictors of hepatocarcinogenesis. In HCV-1b patients, multivariate analysis identified post-treatment Wisteria floribunda agglutinin positive Mac-2 binding protein (>1.8 COI; P = 0.042) and HCV subgroup (HCV-1b with Gln70(His70); P = 0.071), as predictors of hepatocarcinogenesis, including post-treatment parameter. In conclusion, Core aa70 substitution in HCV-1b at the start of direct-acting antiviral therapy is an important predictor of hepatocarcinogenesis following eradication of HCV RNA. This study emphasizes the importance of detection of Core aa70 substitution before initiating antiviral therapy. © 2018 Wiley Periodicals, Inc.

Successes and limitations of targeted therapies in renal cell carcinoma.

PubMed

Pracht, Marc; Berthold, Dominik

2014-01-01

Until recently, the standard treatment for metastatic renal cell carcinoma (RCC) was nonspecific immunotherapy based on interleukin-2 or interferon-α. This was associated with a modest survival benefit and with significant clinical toxicities. The understanding of numerous molecular pathways in RCC, including HIF, VEGF, mTOR, and the consecutive use of targeted therapies since the beginning of 2005 have significantly improved outcomes for patients with metastatic RCC with an overall survival greater than 2 years. At present, at least 7 targeted agents are approved for first and consecutive lines of treatment of clear cell metastatic RCC. Long-term benefit and extended survival may be achieved through the optimal use of targeted therapies: optimal dosing, adverse event management and treatment duration and compliance. Advances in the finding of prognostic factors highlight the potential for personalizing treatment for patients with metastatic RCC. Data regarding the best sequencing of targeted therapies, predictive biomarkers, best timing of surgery, patient risk profiles, understanding of resistance mechanisms and safety of targeted therapies are growing and will provide a further step ahead in the management of advanced RCC. In parallel, a new class of therapeutics is emerging in RCC: immunotherapy; in particular check-point blockade antibodies are showing very promising results. © 2014 S. Karger AG, Basel.

Watchful waiting with periodic liver biopsy versus immediate empirical therapy for histologically mild chronic hepatitis C. A cost-effectiveness analysis.

PubMed

Wong, J B; Koff, R S

2000-11-07

Not all patients with histologically mild chronic hepatitis C progress to cirrhosis. To compare no antiviral treatment, periodic liver biopsy with subsequent antiviral treatment for moderate hepatitis or cirrhosis, and immediate antiviral therapy. Cost-effectiveness analysis. Clinical trial data and published studies. Hepatitis C virus-infected patients with histologically mild hepatitis. Lifetime. Societal. Immediate combination antiviral treatment or biopsy every 3 years plus combination antiviral therapy for moderate hepatitis or cirrhosis. Life expectancy, quality-adjusted life expectancy, and costs. Over 20 years, biopsy every 3 years with treatment of moderate hepatitis would avoid treatment in 50% of the cohort and would result in an 18% likelihood of cirrhosis compared with 16% for immediate treatment and 27% for no antiviral therapy. Immediate antiviral treatment should increase life expectancy by 1.0 quality-adjusted life-year compared with biopsy management. Over an average lifetime, biopsy management would lead to six liver biopsies costing $6200; immediate antiviral treatment would cost $5100 less than biopsy management because of savings related to biopsy and prevention of future hepatitis C-related morbidity. Immediate therapy was cost-effective compared with biopsy management and had a cost-effectiveness ratio of $7000 compared with no antiviral therapy. When age, sex, genotype, and estimates of histologic progression or compliance with follow-up are varied, immediate therapy should result in an increase of at least 0. 8 quality-adjusted life-year compared with biopsy management. For histologically mild chronic hepatitis C, initial combination treatment compared with periodic liver biopsy should reduce the future risk for cirrhosis, prolong life, and be cost-effective.

Discovery of potent broad spectrum antivirals derived from marine actinobacteria.

PubMed

Raveh, Avi; Delekta, Phillip C; Dobry, Craig J; Peng, Weiping; Schultz, Pamela J; Blakely, Pennelope K; Tai, Andrew W; Matainaho, Teatulohi; Irani, David N; Sherman, David H; Miller, David J

2013-01-01

Natural products provide a vast array of chemical structures to explore in the discovery of new medicines. Although secondary metabolites produced by microbes have been developed to treat a variety of diseases, including bacterial and fungal infections, to date there has been limited investigation of natural products with antiviral activity. In this report, we used a phenotypic cell-based replicon assay coupled with an iterative biochemical fractionation process to identify, purify, and characterize antiviral compounds produced by marine microbes. We isolated a compound from Streptomyces kaviengensis, a novel actinomycetes isolated from marine sediments obtained off the coast of New Ireland, Papua New Guinea, which we identified as antimycin A1a. This compound displays potent activity against western equine encephalitis virus in cultured cells with half-maximal inhibitory concentrations of less than 4 nM and a selectivity index of greater than 550. Our efforts also revealed that several antimycin A analogues display antiviral activity, and mechanism of action studies confirmed that these Streptomyces-derived secondary metabolites function by inhibiting the cellular mitochondrial electron transport chain, thereby suppressing de novo pyrimidine synthesis. Furthermore, we found that antimycin A functions as a broad spectrum agent with activity against a wide range of RNA viruses in cultured cells, including members of the Togaviridae, Flaviviridae, Bunyaviridae, Picornaviridae, and Paramyxoviridae families. Finally, we demonstrate that antimycin A reduces central nervous system viral titers, improves clinical disease severity, and enhances survival in mice given a lethal challenge with western equine encephalitis virus. Our results provide conclusive validation for using natural product resources derived from marine microbes as source material for antiviral drug discovery, and they indicate that host mitochondrial electron transport is a viable target for the

Discovery of Potent Broad Spectrum Antivirals Derived from Marine Actinobacteria

PubMed Central

Raveh, Avi; Delekta, Phillip C.; Dobry, Craig J.; Peng, Weiping; Schultz, Pamela J.; Blakely, Pennelope K.; Tai, Andrew W.; Matainaho, Teatulohi; Irani, David N.; Sherman, David H.; Miller, David J.

2013-01-01

Natural products provide a vast array of chemical structures to explore in the discovery of new medicines. Although secondary metabolites produced by microbes have been developed to treat a variety of diseases, including bacterial and fungal infections, to date there has been limited investigation of natural products with antiviral activity. In this report, we used a phenotypic cell-based replicon assay coupled with an iterative biochemical fractionation process to identify, purify, and characterize antiviral compounds produced by marine microbes. We isolated a compound from Streptomyces kaviengensis, a novel actinomycetes isolated from marine sediments obtained off the coast of New Ireland, Papua New Guinea, which we identified as antimycin A1a. This compound displays potent activity against western equine encephalitis virus in cultured cells with half-maximal inhibitory concentrations of less than 4 nM and a selectivity index of greater than 550. Our efforts also revealed that several antimycin A analogues display antiviral activity, and mechanism of action studies confirmed that these Streptomyces-derived secondary metabolites function by inhibiting the cellular mitochondrial electron transport chain, thereby suppressing de novo pyrimidine synthesis. Furthermore, we found that antimycin A functions as a broad spectrum agent with activity against a wide range of RNA viruses in cultured cells, including members of the Togaviridae, Flaviviridae, Bunyaviridae, Picornaviridae, and Paramyxoviridae families. Finally, we demonstrate that antimycin A reduces central nervous system viral titers, improves clinical disease severity, and enhances survival in mice given a lethal challenge with western equine encephalitis virus. Our results provide conclusive validation for using natural product resources derived from marine microbes as source material for antiviral drug discovery, and they indicate that host mitochondrial electron transport is a viable target for the

Antiviral drug research proposal activity.

PubMed

Injaian, Lisa; Smith, Ann C; Shipley, Jennifer German; Marbach-Ad, Gili; Fredericksen, Brenda

2011-01-01

The development of antiviral drugs provides an excellent example of how basic and clinical research must be used together in order to achieve the final goal of treating disease. A Research Oriented Learning Activity was designed to help students to better understand how basic and clinical research can be combined toward a common goal. Through this project students gained a better understanding of the process of scientific research and increased their information literacy in the field of virology. The students worked as teams to research the many aspects involved in the antiviral drug design process, with each student becoming an "expert" in one aspect of the project. The Antiviral Drug Research Proposal (ADRP) culminated with students presenting their proposals to their peers and local virologists in a poster session. Assessment data showed increased student awareness and knowledge of the research process and the steps involved in the development of antiviral drugs as a result of this activity.

Chronic lymphocytic leukemia therapy: new targeted therapies on the way

PubMed Central

Vitale, Candida; Burger, Jan A

2016-01-01

Introduction The critical role of the tissue microenvironment and B cell receptor (BCR) signaling in chronic lymphocytic leukemia (CLL) pathogenesis, and the clinical success of targeted agents that disrupt BCR signaling are currently changing the CLL landscape. Three new drugs were recently approved for CLL therapy, and other agents are in late development. Areas covered In this review, we summarize data on promising new targeted drugs for CLL. The heterogeneous mechanisms of actions of these molecules are described, such as the inhibition of BCR signaling, direct targeting of CD20 molecules on the CLL cell surface, and BCL-2 inhibition. We present preclinical and clinical data from phase I to III studies in order to describe efficacy and side effect profile of these new drugs. Data are derived from peer-reviewed articles indexed in PubMed and from abstracts presented at major international meetings. Expert opinion Ibrutinib and idelalisib are challenging the role of chemo-immunotherapy in CLL therapy in the frontline and relapsed disease settings. High-risk CLL patients particularly benefit from these new agents. Venetoclax and obinutuzumab are other effective agents added to our therapeutic armamentarium. Studies to better define the optimal use of these drugs, alone, or rather in combination or sequenced are underway. PMID:26988407

Palliative chemotherapy and targeted therapies for esophageal and gastroesophageal junction cancer.

PubMed

Janmaat, Vincent T; Steyerberg, Ewout W; van der Gaast, Ate; Mathijssen, Ron Hj; Bruno, Marco J; Peppelenbosch, Maikel P; Kuipers, Ernst J; Spaander, Manon Cw

2017-11-28

Almost half of people with esophageal or gastroesophageal junction cancer have metastatic disease at the time of diagnosis. Chemotherapy and targeted therapies are increasingly used with a palliative intent to control tumor growth, improve quality of life, and prolong survival. To date, and with the exception of ramucirumab, evidence for the efficacy of palliative treatments for esophageal and gastroesophageal cancer is lacking. To assess the effects of cytostatic or targeted therapy for treating esophageal or gastroesophageal junction cancer with palliative intent. We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase, the Web of Science, PubMed Publisher, Google Scholar, and trial registries up to 13 May 2015, and we handsearched the reference lists of studies. We did not restrict the search to publications in English. Additional searches were run in September 2017 prior to publication, and they are listed in the 'Studies awaiting assessment' section. We included randomized controlled trials (RCTs) on palliative chemotherapy and/or targeted therapy versus best supportive care or control in people with esophageal or gastroesophageal junction cancer. Two authors independently extracted data. We assessed the quality and risk of bias of eligible studies according to the Cochrane Handbook for Systematic Reviews of Interventions. We calculated pooled estimates of effect using an inverse variance random-effects model for meta-analysis. We identified 41 RCTs with 11,853 participants for inclusion in the review as well as 49 ongoing studies. For the main comparison of adding a cytostatic and/or targeted agent to a control arm, we included 11 studies with 1347 participants. This analysis demonstrated an increase in overall survival in favor of the arm with an additional cytostatic or targeted therapeutic agent with a hazard ratio (HR) of 0.75 (95% confidence interval (CI) 0.68 to 0.84, high-quality evidence). The median increased

Cancer-targeted therapies and radiopharmaceuticals

PubMed Central

Rachner, Tilman D; Jakob, Franz; Hofbauer, Lorenz C

2015-01-01

The treatment of bone metastases remains a clinical challenge. Although a number of well-established agents, namely bisphosphonates and denosumab, are available to reduce the occurrence of skeletal-related events, additional cancer-targeted therapies are required to improve patients' prognosis and quality of life. This review focuses on novel targets and agents that are under clinical evaluation for the treatment of malignant bone diseases such as activin A, src and endothelin-1 inhibition or agents that are clinically approved and may positively influence bone, such as the mTOR inhibitor everolimus. In addition, the potential of alpharadin, a novel radiopharmaceutical approved for the treatment of prostatic bone disease, is discussed. PMID:26131359

Targeting RNA Splicing for Disease Therapy

PubMed Central

Havens, Mallory A.; Duelli, Dominik M.

2013-01-01

Splicing of pre-messenger RNA into mature messenger RNA is an essential step for expression of most genes in higher eukaryotes. Defects in this process typically affect cellular function and can have pathological consequences. Many human genetic diseases are caused by mutations that cause splicing defects. Furthermore, a number of diseases are associated with splicing defects that are not attributed to overt mutations. Targeting splicing directly to correct disease-associated aberrant splicing is a logical approach to therapy. Splicing is a favorable intervention point for disease therapeutics, because it is an early step in gene expression and does not alter the genome. Significant advances have been made in the development of approaches to manipulate splicing for therapy. Splicing can be manipulated with a number of tools including antisense oligonucleotides, modified small nuclear RNAs (snRNAs), trans-splicing, and small molecule compounds, all of which have been used to increase specific alternatively spliced isoforms or to correct aberrant gene expression resulting from gene mutations that alter splicing. Here we describe clinically relevant splicing defects in disease states, the current tools used to target and alter splicing, specific mutations and diseases that are being targeted using splice-modulating approaches, and emerging therapeutics. PMID:23512601

Targeting RNA splicing for disease therapy.

PubMed

Havens, Mallory A; Duelli, Dominik M; Hastings, Michelle L

2013-01-01

Splicing of pre-messenger RNA into mature messenger RNA is an essential step for the expression of most genes in higher eukaryotes. Defects in this process typically affect cellular function and can have pathological consequences. Many human genetic diseases are caused by mutations that cause splicing defects. Furthermore, a number of diseases are associated with splicing defects that are not attributed to overt mutations. Targeting splicing directly to correct disease-associated aberrant splicing is a logical approach to therapy. Splicing is a favorable intervention point for disease therapeutics, because it is an early step in gene expression and does not alter the genome. Significant advances have been made in the development of approaches to manipulate splicing for therapy. Splicing can be manipulated with a number of tools including antisense oligonucleotides, modified small nuclear RNAs (snRNAs), trans-splicing, and small molecule compounds, all of which have been used to increase specific alternatively spliced isoforms or to correct aberrant gene expression resulting from gene mutations that alter splicing. Here we describe clinically relevant splicing defects in disease states, the current tools used to target and alter splicing, specific mutations and diseases that are being targeted using splice-modulating approaches, and emerging therapeutics. Copyright © 2013 John Wiley & Sons, Ltd.

Molecularly targeted therapies for malignant glioma: rationale for combinatorial strategies

PubMed Central

Thaker, Nikhil G; Pollack, Ian F

2010-01-01

Median survival of patients with malignant glioma (MG) from time of diagnosis is approximately 1 year, despite surgery, irradiation and conventional chemotherapy. Improving patient outcome relies on our ability to develop more effective therapies that are directed against the unique molecular aberrations within a patient’s tumor. Such molecularly targeted therapies may provide novel treatments that are more effective than conventional chemotherapeutics. Recently developed therapeutic strategies have focused on targeting several core glioma signaling pathways, including pathways mediated by growth-factors, PI3K/Akt/PTEN/mTOR, Ras/Raf/MEK/MAPK and other vital pathways. However, given the molecular diversity, heterogeneity and diverging and converging signaling pathways associated with MG, it is unlikely that any single agent will have efficacy in more than a subset of tumors. Overcoming these therapeutic barriers will require multiple agents that can simultaneously inhibit these processes, providing a rationale for combination therapies. This review summarizes the currently implemented single-agent and combination molecularly targeted therapies for MG. PMID:19951140

Suppression of La Antigen Exerts Potential Antiviral Effects against Hepatitis A Virus

PubMed Central

Wu, Shuang; Nakamoto, Shingo; Saito, Kengo; Shirasawa, Hiroshi; Kiyohara, Tomoko; Ishii, Koji; Wakita, Takaji; Okamoto, Hiroaki; Yokosuka, Osamu

2014-01-01

Background Despite the development and availability of hepatitis A virus (HAV) vaccine, HAV infection is still a major cause of acute hepatitis that occasionally leads to fatal liver disease. HAV internal ribosomal entry-site (IRES) is one of the attractive targets of antiviral agents against HAV. The aim of the present study is to evaluate the impact of La, one of the cellular proteins, on HAV IRES-mediated translation and HAV replication. Methods and Findings We investigated the therapeutic feasibility of siRNAs specific for cellular cofactors for HAV IRES-mediated translation in cell culture. It was revealed that siRNA against La could inhibit HAV IRES activities as well as HAV subgenomic replication. We also found that the Janus kinase (JAK) inhibitors SD-1029 and AG490, which reduce La expression, could inhibit HAV IRES activities as well as HAV replication. Conclusions Inhibition of La by siRNAs and chemical agents could lead to the efficient inhibition of HAV IRES-mediated translation and HAV replication in cell culture models. La might play important roles in HAV replication and is being exploited as one of the therapeutic targets of host-targeting antivirals. PMID:24999657

Targeted Therapy: Attacking Cancer with Molecular and Immunological Targeted Agents.

PubMed

Wilkes, Gail M

2018-01-01

Today, personalized cancer therapy with targeted agents has taken center stage, and offers individualized treatment to many. As the mysteries of the genes in a cell's DNA and their specific proteins are defined, advances in the understanding of cancer gene mutations and how cancer evades the immune system have been made. This article provides a basic and simplified understanding of the available (Food and Drug Administration- approved) molecularly and immunologically targeted agents in the USA. Other agents may be available in Asia, and throughout the USA and the world, many more agents are being studied. Nursing implications for drug classes are reviewed.

Personalized targeted therapy for esophageal squamous cell carcinoma

PubMed Central

Kang, Xiaozheng; Chen, Keneng; Li, Yicheng; Li, Jianying; D'Amico, Thomas A; Chen, Xiaoxin

2015-01-01

Esophageal squamous cell carcinoma continues to heavily burden clinicians worldwide. Researchers have discovered the genomic landscape of esophageal squamous cell carcinoma, which holds promise for an era of personalized oncology care. One of the most pressing problems facing this issue is to improve the understanding of the newly available genomic data, and identify the driver-gene mutations, pathways, and networks. The emergence of a legion of novel targeted agents has generated much hope and hype regarding more potent treatment regimens, but the accuracy of drug selection is still arguable. Other problems, such as cancer heterogeneity, drug resistance, exceptional responders, and side effects, have to be surmounted. Evolving topics in personalized oncology, such as interpretation of genomics data, issues in targeted therapy, research approaches for targeted therapy, and future perspectives, will be discussed in this editorial. PMID:26167067

Discovery of host-targeted covalent inhibitors of dengue virus

PubMed Central

de Wispelaere, Mélissanne; Carocci, Margot; Liang, Yanke; Liu, Qingsong; Sun, Eileen; Vetter, Michael L.; Wang, Jinhua; Gray, Nathanael S.; Yang, Priscilla L.

2017-01-01

We report here on an approach targeting the host reactive cysteinome to identify inhibitors of host factors required for the infectious cycle of Flaviviruses and other viruses. We used two parallel cellular phenotypic screens to identify a series of covalent inhibitors, exemplified by QL-XII-47, that are active against dengue virus. We show that the compounds effectively block viral protein expression and that this inhibition is associated with repression of downstream processes of the infectious cycle, and thus significantly contributes to the potent antiviral activity of these compounds. We demonstrate that QL-XII-47’s antiviral activity requires selective, covalent modification of a host target by showing that the compound's antiviral activity is recapitulated when cells are preincubated with QL-XII-47 and then washed prior to viral infection and by showing that QL-XII-47R, a non-reactive analog, lacks antiviral activity at concentrations more than 20-fold higher than QL-XII-47's IC90. QL-XII-47’s inhibition of Zika virus, West Nile virus, hepatitis C virus, and poliovirus further suggests that it acts via a target mediating inhibition of these other medically relevant viruses. These results demonstrate the utility of screens targeting the host reactive cysteinome for rapid identification of compounds with potent antiviral activity. PMID:28034743

Steroid-antivirals treatment versus steroids alone for the treatment of Bell’s palsy: a meta-analysis

PubMed Central

Dong, Yabing; Zhu, Yong; Ma, Chuan; Zhao, Huaqiang

2015-01-01

Background: To illustrate whether the steroid-antivirals treatment could acquire a better recovery in patients with Bell’s palsy than the steroids alone treatment. Materials and methods: We conducted an exhaustive search over Pub med/Medline, Ovid, Elsevier search engines and the Cochrane library thereby collecting the randomized controlled trials in the treatment of patients with Bell’s palsy with steroid-antivirals and steroids. The qualities of relevant articles were assessed by GRADE, which was used to present the overall quality of evidence as recommended by the Cochrane Handbook for Systematic Reviews of Interventions. Results: Two investigators evaluated these papers independently, and resolved the disagreements by discussion. At last 8 eligible papers (1816 patients included: 896 treated with steroid-antivirals and 920 treated with steroids alone) match the criteria. Owing to the result (chi2 = 12.57, P = 0.08, I2 = 44%) presented by the formal test for heterogeneity, the fixed effect meta-analysis model was chosen. The facial muscle recovery between the steroids-antivirals group and the steroids alone group show significant differences (OR = 1.52, 95% CI: 1.20-1.94), while the statistical outcome of adverse effect shows no statistical significance (OR = 1.28, 95% CI: 0.71-2.31). Conclusions: The present meta-analysis indicates that the steroid-antivirals treatment could improve the recovery rate in patients with Bell’s palsy when comparing with the steroid alone treatment. Clinical significance: This meta-analysis showed that the steroid-antivirals treatment achieved the better outcomes in patients with Bell’s palsy. Clinicians should consider that steroid-antivirals therapy is an alternative choice for the patients with Bell’s palsy. PMID:25785012

Tes, a potential Mena-related cancer therapy target.

PubMed

Li, X

2008-02-01

Cancer remains one of the world's most prominent causes of human morbidity and mortality, particularly in developing countries. According to 2005 statistics from the WHO, approximately 7.6 million people died of cancer out of 58 million deaths worldwide, with 9 million people estimated to die from cancer in 2015 and 11.4 million to die in 2030 (http://www.who.int/mediacentre/factsheets/fs297/en/index.html). The principal and internationally recognized methods of cancer treatment are surgery, radiotherapy, chemotherapy, or multimodality therapy. With the recent development of cancer biology, more and more tumor-related targets have been identified, ushering in a new era for target therapy. Every possible step that causes cellular cancer, such as signal transduction pathways, oncogenes and anti-oncogenes, cytokines and receptors, antiangiogenesis, suicide genes, and telomerase (Shay JW, Keith WN. Br J Cancer 2008), that is biologically relevant, reproducibly measurable, and definably correlated with clinical benefit represents a target for target therapies like targeting gene-virotherapy and monoclonal antibody-directed therapy. These therapies can specifically inhibit the growth of tumor cells at the molecular level and even kill them. Generally speaking, cancer-related targets should be crucial to the tumor's malignant phenotype, easily measurable in readily obtained clinical samples, and yield a significant clinical response. Since tumorigenesis is a very complex process involving the interaction of multiple factors and pathways, target treatment offers hopes to maximize efficacy while minimizing toxicity and specificity. More importantly, treatment should have little or no toxicity on normal cells, thus representing the most promising aspect of cancer research (Friday BB, Adjei AA. Clin Cancer Res 2008; 14:342-346). A recent cancer study has provided exciting information. According to Xinhua News from London, Michael Way and fellow researchers from Cancer

What You Should Know about Flu Antiviral Drugs

MedlinePlus

... Other What You Should Know About Flu Antiviral Drugs Language: English (US) Español Recommend on Facebook Tweet ... used to treat flu illness. What are antiviral drugs? Antiviral drugs are prescription medicines (pills, liquid, an ...

Low incidence of hepatitis B virus reactivation and subsequent hepatitis in patients with chronic hepatitis C receiving direct-acting antiviral therapy.

PubMed

Tamori, A; Abiru, S; Enomoto, H; Kioka, K; Korenaga, M; Tani, J; Enomoto, M; Sugiyama, M; Masaki, T; Kawada, N; Yatsuhashi, H; Nishiguchi, S; Mizokami, M

2018-05-01

To determine the clinical characteristics of hepatitis B virus (HBV) reactivation in patients undergoing interferon-free antihepatitis C virus (HCV) therapy, we examined HBV DNA in 25 HBV co-infected patients and 765 patients with resolved HBV infection during and after treatment with direct-acting antiviral agents (DAAs). Among those with HCV genotype 1, asunaprevir plus daclatasvir was administered to 160 patients, sofosbuvir (SOF) plus ledipasvir to 438 patients and paritaprevir plus ombitasvir and ritonavir to 25 patients. In total, 167 patients with genotype 2 were treated with SOF plus ribavirin. Three patients with an HBV DNA level ≥2000 IU/mL were treated with entecavir before anti-HCV therapy, without reactivation of HBV. In 3 of 22 (12%) HBV surface antigen (HBsAg)-positive patients with an HBV DNA level <2000 IU/mL, the viral load increased during treatment. However, hepatitis flare did not occur in these patients. There was no significant difference in clinical history between patients with and without HBV reactivation. Among 765 patients with resolved HBV infection, HBV reactivation occurred in 1 (0.1%) patient after initial resolution, whose HBV DNA level spontaneously decreased after DAA therapy. We compared anti-HBs titres at baseline with those at post-DAA therapy in 123 patients without HBsAg. There was no significant difference in anti-HBs levels between the two points (P = .79). In conclusion, HBV reactivation was rare in HBsAg-negative patients treated with DAA therapy. Additionally, hepatitis did not occur in HBV-reactivated patients with a baseline HBV DNA level <2000 IU/mL before DAA therapy. © 2017 John Wiley & Sons Ltd.

Modelling Ebola virus dynamics: Implications for therapy.

PubMed

Martyushev, Alexey; Nakaoka, Shinji; Sato, Kei; Noda, Takeshi; Iwami, Shingo

2016-11-01

Ebola virus (EBOV) causes a severe, often fatal Ebola virus disease (EVD), for which no approved antivirals exist. Recently, some promising anti-EBOV drugs, which are experimentally potent in animal models, have been developed. However, because the quantitative dynamics of EBOV replication in humans is uncertain, it remains unclear how much antiviral suppression of viral replication affects EVD outcome in patients. Here, we developed a novel mathematical model to quantitatively analyse human viral load data obtained during the 2000/01 Uganda EBOV outbreak and evaluated the effects of different antivirals. We found that nucleoside analogue- and siRNA-based therapies are effective if a therapy with a >50% inhibition rate is initiated within a few days post-symptom-onset. In contrast, antibody-based therapy requires not only a higher inhibition rate but also an earlier administration, especially for otherwise fatal cases. Our results demonstrate that an appropriate choice of EBOV-specific drugs is required for effective EVD treatment. Copyright © 2016 Elsevier B.V. All rights reserved.

Dancing with chemical formulae of antivirals: A panoramic view (Part 2).

PubMed

De Clercq, Erik

2013-11-15

In this second part of "Dancing with antivirals as chemical formulae" I will focus on a number of chemical compounds that in the last few years have elicited more than common attraction from a commercial viewpoint: (i) favipiravir (T-705), as it is active against influenza, but also several other RNA viruses; (ii) neuraminidase inhibitors such as zanamivir and oseltamivir; (iii) peramivir and laninamivir octanoate, which might be effective against influenza virus following a single (intravenous or inhalation) administration; (iv) sofosbuvir, the (anticipated) cornerstone for the interferon-free therapy of HCV infections; (v) combinations of DAAs (direct antiviral agents) to achieve, in no time, a sustained virus response (SVR) against HCV infection; (vi) HIV protease inhibitors, the latest and most promising being darunavir; (vii) the integrase inhibitors (INIs) (raltegravir, elvitegravir, dolutegravir), representing a new dimension in the anti-HIV armamentarium; (viii), a new class of helicase primase inhibitors (HPIs) that may exceed acyclovir and the other anti-herpes compounds in both potency and safety; (ix) CMX-001, as the latest of Dr. Antonín Holý's legacy for its activity against poxviruses and CMV infections, and (x) noroviruses for which the ideal antiviral compounds are still awaited for. Copyright © 2013 Elsevier Inc. All rights reserved.

Chemical genetics-based development of small molecules targeting hepatitis C virus.

PubMed

Jin, Guanghai; Lee, Jisu; Lee, Kyeong

2017-09-01

Hepatitis C virus (HCV) infection is a major worldwide problem that has emerged as one of the most significant diseases affecting humans. There are currently no vaccines or efficient therapies without side effects, despite today's advanced medical technology. Currently, the common therapy for most patients (i.e. genotype 1) is combination of HCV-specific direct-acting antivirals (DAAs). Up to 2011, the standard of care (SOC) was a combination of peg-IFNα with ribavirin (RBV). After approval of NS3/4A protease inhibitor, SOC was peg-IFNα and RBV with either the first-generation DAAs boceprevir or telaprevir. In the past several years, various novel small molecules have been discovered and some of them (i.e., HCV polymerase, protease, helicase and entry inhibitors) have undergone clinical trials. Between 2013 and 2016, the second-generation DAA drugs simeprevir, asunaprevir, daclatasvir, dasabuvir, sofosbuvir, and elbasvir were approved, as well as the combinational drugs Harvoni ® , Zepatier ® , Technivie ® , and Epclusa ® . A number of reviews have been recently published describing the structure-activity relationship (SAR) in the development of HCV inhibitors and outlining current therapeutic approaches to hepatitis C infection. Target identification involves studying a drug's mechanism of action (MOA), and a variety of target identification methods have been developed in the past few years. Chemical biology has emerged as a powerful tool for studying biological processes using small molecules. The use of chemical genetic methods is a valuable strategy for studying the molecular mechanisms of the viral lifecycle and screening for anti-viral agents. Two general screening approaches have been employed: forward and reverse chemical genetics. This review reveals information on the small molecules in HCV drug discovery by using chemical genetics for targeting the HCV protein and describes successful examples of targets identified with these methods.

Viruses and Antiviral Immunity in Drosophila

PubMed Central

Xu, Jie; Cherry, Sara

2013-01-01

Viral pathogens present many challenges to organisms, driving the evolution of a myriad of antiviral strategies to combat infections. A wide variety of viruses infect invertebrates, including both natural pathogens that are insect-restricted, and viruses that are transmitted to vertebrates. Studies using the powerful tools available in the model organism Drosophila have expanded our understanding of antiviral defenses against diverse viruses. In this review, we will cover three major areas. First, we will describe the tools used to study viruses in Drosophila. Second, we will survey the major viruses that have been studied in Drosophila. And lastly, we will discuss the well-characterized mechanisms that are active against these diverse pathogens, focusing on non-RNAi mediated antiviral mechanisms. Antiviral RNAi is discussed in another paper in this issue. PMID:23680639

Antiviral Lectins: Selective Inhibitors of Viral Entry

PubMed Central

Mitchell, Carter A.; Ramessar, Koreen; O’Keefe, Barry R.

2017-01-01

Many natural lectins have been reported to have antiviral activity. As some of these have been put forward as potential development candidates for preventing or treating viral infections, we have set out in this review to survey the literature on antiviral lectins. The review groups lectins by structural class and class of source organism we also detail their carbohydrate specificity and their reported antiviral activities. The review concludes with a brief discussion of several of the pertinent hurdles that heterologous proteins must clear to be useful clinical candidates and cites examples where such studies have been reported for antiviral lectins. Though the clearest path currently being followed is the use of antiviral lectins as anti-HIV microbicides via topical mucosal administration, some investigators have also found systemic efficacy against acute infections following subcutaneous administration. PMID:28322922

Antiviral activity of lauryl gallate against animal viruses.

PubMed

Hurtado, Carolina; Bustos, Maria Jose; Sabina, Prado; Nogal, Maria Luisa; Granja, Aitor G; González, Maria Eugenia; Gónzalez-Porqué, Pedro; Revilla, Yolanda; Carrascosa, Angel L

2008-01-01

Antiviral compounds are needed in the control of many animal and human diseases. We analysed the effect of the antitumoural drug lauryl gallate on the infectivity of the African swine fever virus among other DNA (herpes simplex and vaccinia) and RNA (influenza, porcine transmissible gastroenteritis and Sindbis) viruses, paying attention to its effect on the viability of the corresponding host cells. Viral production was strongly inhibited in different cell lines at non-toxic concentrations of the drug (1-10 microM), reducing the titres 3->5 log units depending on the multiplicity of infection. In our model system (African swine fever virus in Vero cells), the addition of the drug 1 h before virus adsorption completely abolished virus productivity in a one-step growth virus cycle. Interestingly, no inhibitory effect was observed when lauryl gallate was added after 5-8 h post-infection. Both cellular and viral DNA synthesis and late viral transcription were inhibited by the drug; however, the early viral protein synthesis and the virus-mediated increase of p53 remained unaffected. Activation of the apoptotic effector caspase-3 was not detected after lauryl gallate treatment of Vero cells. Furthermore, the presence of the drug abrogated the activation of this protease induced by the virus infection. Lauryl gallate is a powerful antiviral agent against several pathogens of clinical and veterinary importance. The overall results indicate that a cellular factor or function might be the target of the antiviral action of alkyl gallates.

Broad spectrum antiviral agent ribavirin inhibits capping of mRNA

DOE Office of Scientific and Technical Information (OSTI.GOV)

Goswami, B.B.; Borek, E.; Sharma, O.K.

1979-08-13

Ribavirin (1-..beta..-D-ribofuranosyl-1,2,4-triazole-3-carboxamide) is a broad spectrum antiviral substance active against a wide range of both DNA and RNA viruses. It is, however, virtually inactive against polio virus. Its pharmacological mechanism of action was obscure. A possible common target for a chemotherapeutic agent in both DNA and RNA viruses is the capping reaction of mRNAs which inter alia involves the formation of a guanine pyrophosphate structure at the 5' terminus by mRNA guanylyl transferase. We have observed that Ribavirin triphosphate is a potent competitive inhibitor of the capping guanylation of viral mRNA. This finding could account for the antiviral potency ofmore » the drug against both DNA and RNA viruses and its ineffectiveness against a virus in which the mRNAs derived from them are not capped.« less

Toll-Like Receptor 7 Agonist GS-9620 Induces HIV Expression and HIV-Specific Immunity in Cells from HIV-Infected Individuals on Suppressive Antiretroviral Therapy.

PubMed

Tsai, Angela; Irrinki, Alivelu; Kaur, Jasmine; Cihlar, Tomas; Kukolj, George; Sloan, Derek D; Murry, Jeffrey P

2017-04-15

Antiretroviral therapy can suppress HIV replication to undetectable levels but does not eliminate latent HIV, thus necessitating lifelong therapy. Recent efforts to target this persistent reservoir have focused on inducing the expression of latent HIV so that infected cells may be recognized and eliminated by the immune system. Toll-like receptor (TLR) activation stimulates antiviral immunity and has been shown to induce HIV from latently infected cells. Activation of TLR7 leads to the production of several stimulatory cytokines, including type I interferons (IFNs). In this study, we show that the selective TLR7 agonist GS-9620 induced HIV in peripheral blood mononuclear cells (PBMCs) from HIV-infected individuals on suppressive antiretroviral therapy. GS-9620 increased extracellular HIV RNA 1.5- to 2-fold through a mechanism that required type I IFN signaling. GS-9620 also activated HIV-specific T cells and enhanced antibody-mediated clearance of HIV-infected cells. Activation by GS-9620 in combination with HIV peptide stimulation increased CD8 T cell degranulation, production of intracellular cytokines, and cytolytic activity. T cell activation was again dependent on type I IFNs produced by plasmacytoid dendritic cells. GS-9620 induced phagocytic cell maturation and improved effector-mediated killing of HIV-infected CD4 T cells by the HIV envelope-specific broadly neutralizing antibody PGT121. Collectively, these data show that GS-9620 can activate HIV production and improve the effector functions that target latently infected cells. GS-9620 may effectively complement orthogonal therapies designed to stimulate antiviral immunity, such as therapeutic vaccines or broadly neutralizing antibodies. Clinical studies are under way to determine if GS-9620 can target HIV reservoirs. IMPORTANCE Though antiretroviral therapies effectively suppress viral replication, they do not eliminate integrated proviral DNA. This stable intermediate of viral infection is persistently

Toll-Like Receptor 7 Agonist GS-9620 Induces HIV Expression and HIV-Specific Immunity in Cells from HIV-Infected Individuals on Suppressive Antiretroviral Therapy

PubMed Central

Tsai, Angela; Irrinki, Alivelu; Kaur, Jasmine; Cihlar, Tomas; Kukolj, George

2017-01-01

ABSTRACT Antiretroviral therapy can suppress HIV replication to undetectable levels but does not eliminate latent HIV, thus necessitating lifelong therapy. Recent efforts to target this persistent reservoir have focused on inducing the expression of latent HIV so that infected cells may be recognized and eliminated by the immune system. Toll-like receptor (TLR) activation stimulates antiviral immunity and has been shown to induce HIV from latently infected cells. Activation of TLR7 leads to the production of several stimulatory cytokines, including type I interferons (IFNs). In this study, we show that the selective TLR7 agonist GS-9620 induced HIV in peripheral blood mononuclear cells (PBMCs) from HIV-infected individuals on suppressive antiretroviral therapy. GS-9620 increased extracellular HIV RNA 1.5- to 2-fold through a mechanism that required type I IFN signaling. GS-9620 also activated HIV-specific T cells and enhanced antibody-mediated clearance of HIV-infected cells. Activation by GS-9620 in combination with HIV peptide stimulation increased CD8 T cell degranulation, production of intracellular cytokines, and cytolytic activity. T cell activation was again dependent on type I IFNs produced by plasmacytoid dendritic cells. GS-9620 induced phagocytic cell maturation and improved effector-mediated killing of HIV-infected CD4 T cells by the HIV envelope-specific broadly neutralizing antibody PGT121. Collectively, these data show that GS-9620 can activate HIV production and improve the effector functions that target latently infected cells. GS-9620 may effectively complement orthogonal therapies designed to stimulate antiviral immunity, such as therapeutic vaccines or broadly neutralizing antibodies. Clinical studies are under way to determine if GS-9620 can target HIV reservoirs. IMPORTANCE Though antiretroviral therapies effectively suppress viral replication, they do not eliminate integrated proviral DNA. This stable intermediate of viral infection is

Addressing the selectivity and toxicity of antiviral nucleosides.

PubMed

Feng, Joy Y

2018-01-01

Nucleoside and nucleotide analogs have played significant roles in antiviral therapies and are valued for their impressive potency and high barrier to resistance. They have been approved for treatment of herpes simplex virus-1, HIV, HBV, HCV, and influenza, and new drugs are being developed for the treatment of RSV, Ebola, coronavirus MERS, and other emerging viruses. However, this class of compounds has also experienced a high attrition rate in clinical trials due to toxicity. In this review, we discuss the utility of different biochemical and cell-based assays and provide recommendations for assessing toxicity liability before entering animal toxicity studies.

Development of targeted therapy and immunotherapy for treatment of small cell lung cancer.

PubMed

Saito, Motonobu; Shiraishi, Kouya; Goto, Akiteru; Suzuki, Hiroyuki; Kohno, Takashi; Kono, Koji

2018-05-14

Targeted therapy against druggable genetic aberrations has shown a significantly positive response rate and longer survival in various cancers, including lung cancer. In lung adenocarcinoma (LADC), specific thyroxin kinase inhibitors against EGFR mutations and ALK fusions are used as a standard treatment regimen and show significant positive efficacy. On the other hand, targeted therapy against driver gene aberrations has not been adapted yet in small cell lung cancer (SCLC). This is because driver genes and druggable aberrations are rarely identified by next generation sequencing in SCLC. Recent advances in the understanding of molecular biology have revealed several candidate therapeutic targets. To date, poly [ADP-ribose] polymerase (PARP), enhancer of zeste homologue 2 (EZH2) or delta-like canonical Notch ligand 3 (DLL3) are considered to be druggable targets in SCLC. In addition, another candidate of personalized therapy for SCLC is immune blockade therapy of programmed death-1 (PD-1) and its ligand, PD-L1. PD-1/PD-L1 blockade therapy is not a standard therapy for SCLC, so many clinical trials have been performed to investigate its efficacy. Herein, we review gene aberrations exploring the utility of targeted therapy and discuss blockade of immune checkpoints therapy in SCLC.

Targeted Therapies in Non-Small Cell Lung Cancer—Beyond EGFR and ALK

PubMed Central

Rothschild, Sacha I.

2015-01-01

Systemic therapy for non-small cell lung cancer (NSCLC) has undergone a dramatic paradigm shift over the past decade. Advances in our understanding of the underlying biology of NSCLC have revealed distinct molecular subtypes. A substantial proportion of NSCLC depends on oncogenic molecular aberrations (so-called “driver mutations”) for their malignant phenotype. Personalized therapy encompasses the strategy of matching these subtypes with effective targeted therapies. EGFR mutations and ALK translocation are the most effectively targeted oncogenes in NSCLC. EGFR mutations and ALK gene rearrangements are successfully being targeted with specific tyrosine kinase inhibitors. The number of molecular subgroups of NSCLC continues to grow. The scope of this review is to discuss recent data on novel molecular targets as ROS1, BRAF, KRAS, HER2, c-MET, RET, PIK3CA, FGFR1 and DDR2. Thereby the review will focus on therapeutic strategies targeting these aberrations. Moreover, the emerging challenge of acquired resistance to initially effective therapies will be discussed. PMID:26018876

Targeted Therapies in Non-Small Cell Lung Cancer-Beyond EGFR and ALK.

PubMed

Rothschild, Sacha I

2015-05-26

Systemic therapy for non-small cell lung cancer (NSCLC) has undergone a dramatic paradigm shift over the past decade. Advances in our understanding of the underlying biology of NSCLC have revealed distinct molecular subtypes. A substantial proportion of NSCLC depends on oncogenic molecular aberrations (so-called "driver mutations") for their malignant phenotype. Personalized therapy encompasses the strategy of matching these subtypes with effective targeted therapies. EGFR mutations and ALK translocation are the most effectively targeted oncogenes in NSCLC. EGFR mutations and ALK gene rearrangements are successfully being targeted with specific tyrosine kinase inhibitors. The number of molecular subgroups of NSCLC continues to grow. The scope of this review is to discuss recent data on novel molecular targets as ROS1, BRAF, KRAS, HER2, c-MET, RET, PIK3CA, FGFR1 and DDR2. Thereby the review will focus on therapeutic strategies targeting these aberrations. Moreover, the emerging challenge of acquired resistance to initially effective therapies will be discussed.

Anticancer kinase inhibitors impair intracellular viral trafficking and exert broad-spectrum antiviral effects.

PubMed

Bekerman, Elena; Neveu, Gregory; Shulla, Ana; Brannan, Jennifer; Pu, Szu-Yuan; Wang, Stanley; Xiao, Fei; Barouch-Bentov, Rina; Bakken, Russell R; Mateo, Roberto; Govero, Jennifer; Nagamine, Claude M; Diamond, Michael S; De Jonghe, Steven; Herdewijn, Piet; Dye, John M; Randall, Glenn; Einav, Shirit

2017-04-03

Global health is threatened by emerging viral infections, which largely lack effective vaccines or therapies. Targeting host pathways that are exploited by multiple viruses could offer broad-spectrum solutions. We previously reported that AAK1 and GAK, kinase regulators of the host adaptor proteins AP1 and AP2, are essential for hepatitis C virus (HCV) infection, but the underlying mechanism and relevance to other viruses or in vivo infections remained unknown. Here, we have discovered that AP1 and AP2 cotraffic with HCV particles in live cells. Moreover, we found that multiple viruses, including dengue and Ebola, exploit AAK1 and GAK during entry and infectious virus production. In cultured cells, treatment with sunitinib and erlotinib, approved anticancer drugs that inhibit AAK1 or GAK activity, or with more selective compounds inhibited intracellular trafficking of HCV and multiple unrelated RNA viruses with a high barrier to resistance. In murine models of dengue and Ebola infection, sunitinib/erlotinib combination protected against morbidity and mortality. We validated sunitinib- and erlotinib-mediated inhibition of AAK1 and GAK activity as an important mechanism of antiviral action. Additionally, we revealed potential roles for additional kinase targets. These findings advance our understanding of virus-host interactions and establish a proof of principle for a repurposed, host-targeted approach to combat emerging viruses.

Anticancer kinase inhibitors impair intracellular viral trafficking and exert broad-spectrum antiviral effects

PubMed Central

Bekerman, Elena; Shulla, Ana; Brannan, Jennifer; Wang, Stanley; Barouch-Bentov, Rina; Bakken, Russell R.; Mateo, Roberto; Govero, Jennifer; Nagamine, Claude M.; Diamond, Michael S.; De Jonghe, Steven; Herdewijn, Piet; Dye, John M.; Randall, Glenn

2017-01-01

Global health is threatened by emerging viral infections, which largely lack effective vaccines or therapies. Targeting host pathways that are exploited by multiple viruses could offer broad-spectrum solutions. We previously reported that AAK1 and GAK, kinase regulators of the host adaptor proteins AP1 and AP2, are essential for hepatitis C virus (HCV) infection, but the underlying mechanism and relevance to other viruses or in vivo infections remained unknown. Here, we have discovered that AP1 and AP2 cotraffic with HCV particles in live cells. Moreover, we found that multiple viruses, including dengue and Ebola, exploit AAK1 and GAK during entry and infectious virus production. In cultured cells, treatment with sunitinib and erlotinib, approved anticancer drugs that inhibit AAK1 or GAK activity, or with more selective compounds inhibited intracellular trafficking of HCV and multiple unrelated RNA viruses with a high barrier to resistance. In murine models of dengue and Ebola infection, sunitinib/erlotinib combination protected against morbidity and mortality. We validated sunitinib- and erlotinib-mediated inhibition of AAK1 and GAK activity as an important mechanism of antiviral action. Additionally, we revealed potential roles for additional kinase targets. These findings advance our understanding of virus-host interactions and establish a proof of principle for a repurposed, host-targeted approach to combat emerging viruses. PMID:28240606

Final Report of Unmet Needs of Interferon-Based Therapy for Chronic Hepatitis C in Korea: Basis for Moving into the Direct-Acting Antiviral Era

PubMed Central

Jang, Eun Sun; Kim, Young Seok; Kim, Kyung-Ah; Lee, Youn Jae; Chung, Woo Jin; Kim, In Hee; Lee, Byung Seok; Jeong, Sook-Hyang

2017-01-01

Background/Aims To evaluate the era of direct acting antivirals (DAAs), we must understand the treatment patterns and outcomes of interferon-based therapy for hepatitis C virus (HCV) infection. We aimed to elucidate the treatment rate, factors affecting treatment decisions, and efficacy of interferon-based therapy in a real-world setting. Methods This nationwide cohort study included 1,191 newly diagnosed patients with chronic HCV infection at seven tertiary hospitals in South Korea. Subjects were followed retrospectively until March 2015, which was just before the approval of DAA therapy. Results In total, 48.2% and 49.3% of the patients had HCV genotypes 1 and 2, respectively. Interferon-based therapy was initiated in 541 patients (45.4%). The major reasons for no treatment included ineligibility (18.9%), concern about adverse events (22.3%), cost (21.5%), and an age >75 years (19.5%). Interferon-based therapy was discontinued (18.5%) mainly due to adverse events (n=66). The intent-to-treat analysis found that the sustained virologic response (SVR) rate was 58.3% in genotype 1 patients and 74.7% in non-genotype 1 patients. Conclusions Approximately one-third of newly diagnosed HCV patients in South Korea received interferon-based therapy and showed a suboptimal SVR rate. Diagnosis of patients at younger ages and with a less advanced liver status and reducing the DAA therapy cost may fulfill unmet needs. PMID:28506027

Ultrasensitive HCV RNA Quantification in Antiviral Triple Therapy: New Insight on Viral Clearance Dynamics and Treatment Outcome Predictors

PubMed Central

Garbuglia, Anna Rosa; Visco-Comandini, Ubaldo; Lionetti, Raffaella; Lapa, Daniele; Castiglione, Filippo; D’Offizi, Gianpiero; Taibi, Chiara; Montalbano, Marzia; Capobianchi, Maria Rosaria; Paci, Paola

2016-01-01

Objectives Identifying the predictive factors of Sustained Virological Response (SVR) represents an important challenge in new interferon-based DAA therapies. Here, we analyzed the kinetics of antiviral response associated with a triple drug regimen, and the association between negative residual viral load at different time points during treatment. Methods Twenty-three HCV genotype 1 (GT 1a n = 11; GT1b n = 12) infected patients were included in the study. Linear Discriminant Analysis (LDA) was used to establish possible association between HCV RNA values at days 1 and 4 from start of therapy and SVR. Principal component analysis (PCA) was applied to analyze the correlation between HCV RNA slope and SVR. A ultrasensitive (US) method was established to measure the residual HCV viral load in those samples which resulted “detected <12IU/ml” or undetectable with ABBOTT standard assay, and was retrospectively used on samples collected at different time points to establish its predictive power for SVR. Results According to LDA, there was no association between SVR and viral kinetics neither at time points earlier than 1 week (days 1 and 4) after therapy initiation nor later. The slopes were not relevant for classifying patients as SVR or no-SVR. No significant differences were observed in the median HCV RNA values at T0 among SVR and no-SVR patients. HCV RNA values with US protocol (LOD 1.2 IU/ml) after 1 month of therapy were considered; the area under the ROC curve was 0.70. Overall, PPV and NPV of undetectable HCV RNA with the US method for SVR was 100% and 46.7%, respectively; sensitivity and specificity were 38.4% and 100% respectively. Conclusion HCV RNA “not detected” by the US method after 1 month of treatment is predictive of SVR in first generation Protease inhibitor (PI)-based triple therapy. The US method could have clinical utility for advanced monitoring of virological response in new interferon based DAA combination regimens. PMID:27560794

The Mechanisms for Within-Host Influenza Virus Control Affect Model-Based Assessment and Prediction of Antiviral Treatment

PubMed Central

Cao, Pengxing

2017-01-01

Models of within-host influenza viral dynamics have contributed to an improved understanding of viral dynamics and antiviral effects over the past decade. Existing models can be classified into two broad types based on the mechanism of viral control: models utilising target cell depletion to limit the progress of infection and models which rely on timely activation of innate and adaptive immune responses to control the infection. In this paper, we compare how two exemplar models based on these different mechanisms behave and investigate how the mechanistic difference affects the assessment and prediction of antiviral treatment. We find that the assumed mechanism for viral control strongly influences the predicted outcomes of treatment. Furthermore, we observe that for the target cell-limited model the assumed drug efficacy strongly influences the predicted treatment outcomes. The area under the viral load curve is identified as the most reliable predictor of drug efficacy, and is robust to model selection. Moreover, with support from previous clinical studies, we suggest that the target cell-limited model is more suitable for modelling in vitro assays or infection in some immunocompromised/immunosuppressed patients while the immune response model is preferred for predicting the infection/antiviral effect in immunocompetent animals/patients. PMID:28933757

Week 4 viral load predicts long-term suppression of hepatitis B virus DNA during antiviral therapy: improving hepatitis B treatment in the real world.

PubMed

Truong, J; Shadbolt, B; Ooi, M; Chitturi, S; Kaye, G; Farrell, G C; Teoh, N C

2017-01-01

Entecavir and tenofovir potently suppress hepatitis B virus (HBV) replication so that serum HBV DNA levels <20 IU/mL can be achieved after 2 years. Despite this, inadequate suppression is reported in >20% of cases for unclear reasons. We tested whether 4-week viral load (VL) assessment could improve 96-week treatment outcome. Data on all chronic hepatitis B patients treated with entecavir or tenofovir between 2005 and 2014 were entered prospectively. Full data capture included pre-treatment, weeks 4, 24, 48 and 96 HBV DNA titre, HBeAg, age, gender, antiviral agent and dose escalation. Compliance data were compiled from pharmacy records, doctors' letters and clinic bookings/attendance. Time to achieve complete viral suppression (HBV DNA < 20 IU/mL) was graphed using Kaplan-Meier curves. Factors affecting this were examined using a multivariate Cox Proportional Hazard model. Among 156 patients treated, 72 received entecavir and 84 tenofovir. Pre-treatment HBV DNA titre, 4-week assessment and compliance impacted significantly on time to complete viral suppression. At 96 weeks, 90% of those assessed as compliant by 4-week HBV DNA had complete viral suppression versus 50% followed by 6-month VL estimation. Continuing care by the same physician was related to 4-week VL testing and optimal compliance. Medium-term outcomes of HBV antiviral therapy are improved by early on-treatment VL testing, facilitating patient engagement and improved compliance. The observation that 90% complete viral suppression after 2 years monotherapy is achievable in a routine clinic setting questions the need for combination therapy in HBV cases with suboptimal response. © 2016 Royal Australasian College of Physicians.

Cell-type-specific, Aptamer-functionalized Agents for Targeted Disease Therapy

PubMed Central

Zhou, Jiehua; Rossi, John J.

2014-01-01

One hundred years ago, Dr. Paul Ehrlich popularized the “magic bullet” concept for cancer therapy in which an ideal therapeutic agent would only kill the specific tumor cells it targeted. Since then, “targeted therapy” that specifically targets the molecular defects responsible for a patient's condition has become a long-standing goal for treating human disease. However, safe and efficient drug delivery during the treatment of cancer and infectious disease remains a major challenge for clinical translation and the development of new therapies. The advent of SELEX technology has inspired many groundbreaking studies that successfully adapted cell-specific aptamers for targeted delivery of active drug substances in both in vitro and in vivo models. By covalently linking or physically functionalizing the cell-specific aptamers with therapeutic agents, such as siRNA, microRNA, chemotherapeutics or toxins, or delivery vehicles, such as organic or inorganic nanocarriers, the targeted cells and tissues can be specifically recognized and the therapeutic compounds internalized, thereby improving the local concentration of the drug and its therapeutic efficacy. Currently, many cell-type-specific aptamers have been developed that can target distinct diseases or tissues in a cell-type-specific manner. In this review, we discuss recent advances in the use of cell-specific aptamers for targeted disease therapy, as well as conjugation strategies and challenges. PMID:24936916

Application of stem cells in targeted therapy of breast cancer: a systematic review.

PubMed

Madjd, Zahra; Gheytanchi, Elmira; Erfani, Elham; Asadi-Lari, Mohsen

2013-01-01

The aim of this systematic review was to investigate whether stem cells could be effectively applied in targeted therapy of breast cancer. A systematic literature search was performed for original articles published from January 2007 until May 2012. Nine studies met the inclusion criteria for phase I or II clinical trials, of which three used stem cells as vehicles, two trials used autologous hematopoetic stem cells and in four trials cancer stem cells were targeted. Mesenchymal stem cells (MSCs) were applied as cellular vehicles to transfer therapeutic agents. Cell therapy with MSC can successfully target resistant cancers. Cancer stem cells were selectively targeted via a proteasome-dependent suicide gene leading to tumor regression. Wnt/β-catenin signaling pathway has been also evidenced to be an attractive CSC-target. This systematic review focused on two different concepts of stem cells and breast cancer marking a turning point in the trials that applied stem cells as cellular vehicles for targeted delivery therapy as well as CSC-targeted therapies. Applying stem cells as targeted therapy could be an effective therapeutic approach for treatment of breast cancer in the clinic and in therapeutic marketing; however this needs to be confirmed with further clinical investigations.

Targeted Therapy: Attacking Cancer with Molecular and Immunological Targeted Agents

PubMed Central

Wilkes, Gail M.

2018-01-01

Today, personalized cancer therapy with targeted agents has taken center stage, and offers individualized treatment to many. As the mysteries of the genes in a cell's DNA and their specific proteins are defined, advances in the understanding of cancer gene mutations and how cancer evades the immune system have been made. This article provides a basic and simplified understanding of the available (Food and Drug Administration- approved) molecularly and immunologically targeted agents in the USA. Other agents may be available in Asia, and throughout the USA and the world, many more agents are being studied. Nursing implications for drug classes are reviewed. PMID:29607374

Viruses and antiviral immunity in Drosophila.

PubMed

Xu, Jie; Cherry, Sara

2014-01-01

Viral pathogens present many challenges to organisms, driving the evolution of a myriad of antiviral strategies to combat infections. A wide variety of viruses infect invertebrates, including both natural pathogens that are insect-restricted, and viruses that are transmitted to vertebrates. Studies using the powerful tools in the model organism Drosophila have expanded our understanding of antiviral defenses against diverse viruses. In this review, we will cover three major areas. First, we will describe the tools used to study viruses in Drosophila. Second, we will survey the major viruses that have been studied in Drosophila. And lastly, we will discuss the well-characterized mechanisms that are active against these diverse pathogens, focusing on non-RNAi mediated antiviral mechanisms. Antiviral RNAi is discussed in another paper in this issue. Copyright © 2013 Elsevier Ltd. All rights reserved.

The antiviral potency of Fagus sylvatica 4OMe-glucuronoxylan sulfates.

PubMed

Pujol, C A; Damonte, E B; Turjan, J; Yanbo, K Z; Capek, P

2016-06-01

Herpes simplex virus belongs to Herpesviridae family and causes infection of humans from ancient times. 4OMe-glucuronoxylans as the renewable biopolymers can be promising glycomaterials for various applications in pharmacy. Control enzymatic degradation of the native 4OMe-glucuronoxylan (GX1) followed by targeted sulfation procedure afforded a range of 4OMe-glucuronoxylan sulfates differed in the degree of sulfation (10-16%) and molecular mass (21,000-5000g/mol; GXS1>GXS2>GXS3>GXS4). Antiviral activity tests on GXS1-4 against herpes simplex virus (HSV) types 1 and 2 revealed the positive effect of all compounds against strains of herpes virus. Of them, the compounds GXS1 and GXS4 were shown to be the most active for both HSV serotypes. The antiviral activity of GXS1 and GXS4 was similar to those of heparin or dextran sulfate, used as reference compounds. It was found that GXS1 and GXS4 were active as well against Polio and dengue viruses, however, on a smaller scale. The mode of antiviral action of 4OMe-glucuronoxylan sulfates is due to inhibition of the virus binding to the cell receptors. Copyright © 2016 Elsevier B.V. All rights reserved.

Targeting neutrophils for host-directed therapy to treat tuberculosis.

PubMed

Dallenga, Tobias; Linnemann, Lara; Paudyal, Bhesh; Repnik, Urska; Griffiths, Gareth; Schaible, Ulrich E

2017-10-07

M. tuberculosis is one of the prime killers from infectious diseases worldwide. Infections with multidrug-resistant variants counting for almost half a million new cases per year are steadily on the rise. Tuberculosis caused by extensively drug-resistant variants that are even resistant against newly developed or last resort antibiotics have to be considered untreaTable Susceptible tuberculosis already requires a six-months combinational therapy which requires further prolongation to treat drug-resistant infections. Such long treatment schedules are often accompanied by serious adverse effects causing patients to stop therapy. To tackle the global tuberculosis emergency, novel approaches for treatment need to be urgently explored. Host-directed therapies that target components of the defense system represent such a novel approach. In this review, we put a spotlight on neutrophils and neutrophil-associated effectors as promising targets for adjunct host-directed therapies to improve antibiotic efficacy and reduce both, treatment time and long-term pathological sequelae. Copyright © 2017 Elsevier GmbH. All rights reserved.

Orange juice as dietary source of antioxidants for patients with hepatitis C under antiviral therapy.

PubMed

Gonçalves, Danielle; Lima, Claudia; Ferreira, Paula; Costa, Paulo; Costa, Angela; Figueiredo, Walter; Cesar, Thais

2017-01-01

Background: HCV causes alterations in liver metabolism, resulting in biochemical and nutritional disorders. Supplementation with antioxidants has been suggested to minimize the diseases effects. Objective: This study assessed whether orange juice, a source of citrus flavonoids and vitamin C, may contribute to the treatment of patients with chronic hepatitis C. Design: Anthropometric, hemodynamic, dietary, and biochemical parameters, CRP and liver enzymes were measured in 43 adult patients of both genders who were diagnosed with chronic hepatitis C and were under antiviral therapy. Twenty-three patients were supplemented with orange juice for eight consecutive weeks, while 20 were enrolled as control group. Results: Following regular use of orange juice, no alterations were found in body mass, fat, and waist circumference. The serum levels of total cholesterol, LDL-cholesterol, CRP and parameters of oxidative stress decreased in the orange juice group. Furthermore, the levels of the liver enzyme AST decreased in those who had high levels before the intervention. Conclusion: The orange juice was a convenient food in the diet of patients due to the increase in antioxidant capacity and decreased inflammation and cholesterol in blood serum, in addition to maintaining body mass, which protect against the harmful effects caused by the chronic hepatitis C virus.​​​.

Orange juice as dietary source of antioxidants for patients with hepatitis C under antiviral therapy

PubMed Central

Gonçalves, Danielle; Lima, Claudia; Ferreira, Paula; Costa, Paulo; Costa, Angela; Figueiredo, Walter; Cesar, Thais

2017-01-01

ABSTRACT Background: HCV causes alterations in liver metabolism, resulting in biochemical and nutritional disorders. Supplementation with antioxidants has been suggested to minimize the diseases effects. Objective: This study assessed whether orange juice, a source of citrus flavonoids and vitamin C, may contribute to the treatment of patients with chronic hepatitis C. Design: Anthropometric, hemodynamic, dietary, and biochemical parameters, CRP and liver enzymes were measured in 43 adult patients of both genders who were diagnosed with chronic hepatitis C and were under antiviral therapy. Twenty-three patients were supplemented with orange juice for eight consecutive weeks, while 20 were enrolled as control group. Results: Following regular use of orange juice, no alterations were found in body mass, fat, and waist circumference. The serum levels of total cholesterol, LDL-cholesterol, CRP and parameters of oxidative stress decreased in the orange juice group. Furthermore, the levels of the liver enzyme AST decreased in those who had high levels before the intervention. Conclusion: The orange juice was a convenient food in the diet of patients due to the increase in antioxidant capacity and decreased inflammation and cholesterol in blood serum, in addition to maintaining body mass, which protect against the harmful effects caused by the chronic hepatitis C virus.​​​ PMID:28469541

Simultaneous titration and phenotypic antiviral drug susceptibility testing for herpes simplex virus 1 and 2.

PubMed

Tardif, Keith D; Jorgensen, Shane; Langer, Janine; Prichard, Mark; Schlaberg, Robert

2014-11-01

Most herpes simplex virus (HSV) isolates from treatment-naïve patients are susceptible to antivirals. However, prolonged antiviral therapy can select for drug-resistant strains, especially in immunocompromised patients. Standard phenotypic methods for antiviral resistance testing are labor and time-intense and molecular resistance determinants are insufficiently understood for routine diagnostic use of genotypic resistance testing. To enable rapid, scalable antiviral susceptibility testing and minimize viral passage, we developed a 7-day, 96-well assay for simultaneous HSV 1/2 titration and phenotypic resistance testing for acyclovir and foscarnet. The assay was optimized and validated by testing clinical isolates and laboratory strains (n=39) with known IC50 for acyclovir (23 resistant) and foscarnet (1 resistant) based on plaque reduction or dye-uptake assays. A chemiluminescent detection reagent is used for quantification of cytopathic effect instead of plaque counting or measuring dye-uptake. Drug concentrations inhibiting 50% of chemiluminescent signal reduction (IC50) were determined concurrently at each of three virus dilutions. Results agree for 92.3% (acyclovir) and 100% (foscarnet) of isolates. For all three discordant samples, results of reference testing by plaque reduction agreed with the chemiluminescent assay. Reproducibility studies showed 100% qualitative agreement and 3-37% coefficient of variation based on IC50. Chemiluminescence detection as a surrogate for cellular viability with an automated plate reader provides improved throughput and workflow, as well as high accuracy and reproducibility for antiviral drug susceptibility testing. Copyright © 2014 Elsevier B.V. All rights reserved.

Clinical impact of non-organ-specific autoantibodies on the response to combined antiviral treatment in patients with hepatitis C.

PubMed

Muratori, Paolo; Muratori, Luigi; Guidi, Marcello; Granito, Alessandro; Susca, Micaela; Lenzi, Marco; Bianchi, Francesco B

2005-02-15

Hepatitis C virus (HCV)-related chronic hepatitis is frequently associated with non-organ-specific autoantibodies (NOSAs), but available data about the relationship between NOSA positivity and the effect of antiviral therapy in persons with hepatitis C are few and controversial. Our aim was to evaluate the impact of NOSA positivity on the outcome of combined antiviral therapy in HCV-positive patients. A total of 143 consecutive adult patients with hepatitis C were studied. Antinuclear antibody (ANA), anti-smooth muscle antibody (SMA), and anti-liver/kidney microsomal antibody type 1 (LKM1) were detected by indirect immunofluorescence. All patients were treatment naive and received combined antiviral therapy (interferon [IFN]-ribavirin) after enrollment in the study. Patients were classified as nonresponders if HCV RNA was detectable after 6 months of therapy, as relapsers if abnormal transaminase levels and reactivation of HCV replication were observed after the end of treatment, and as long-term responders if transaminase levels were persistently normal and HCV RNA was undetectable 6 months after the end of treatment. Thirty-seven patients (25%) were NOSA positive (SMA was detected in 19 patients, ANA in 10, ANA and SMA in 4, LKM1 in 3, and SMA and LKM1 in 1). The prevalence of long-term response was similar between NOSA-positive patients and NOSA-negative patients (48.6% vs. 56.6%; P=not significant). Compared with HCV genotype 1 (HCV-1), HCV genotypes other than 1 were more often associated with long-term response among NOSA-positive patients (93.3% vs. 30%; P=.0017). The overall rate of long-term response, irrespective of NOSA status, was 54.5%. Detection of HCV-1 and elevated gamma-glutamyl transpeptidase serum levels were independent negative prognostic factors of treatment response (P=.007 and P=.026, respectively). Combined antiviral treatment (IFN-ribavirin) is safe and effective in NOSA-positive patients with hepatitis C, even if long-term response is

Review of the current targeted therapies for non-small-cell lung cancer

PubMed Central

Nguyen, Kim-Son H; Neal, Joel W; Wakelee, Heather

2014-01-01

The last decade has witnessed the development of oncogene-directed targeted therapies that have significantly changed the treatment of non-small-cell lung cancer (NSCLC). In this paper we review the data demonstrating efficacy of gefitinib, erlotinib, and afatinib, which target the epidermal growth factor receptor (EGFR), and crizotinib which targets anaplastic lymphoma kinase (ALK). We discuss the challenge of acquired resistance to these small-molecular tyrosine kinase inhibitors and review promising agents which may overcome resistance, including the EGFR T790M-targeted agents CO-1686 and AZD9291, and the ALK-targeted agents ceritinib (LDK378), AP26113, alectinib (CH/RO5424802), and others. Emerging therapies directed against other driver oncogenes in NSCLC including ROS1, HER2, and BRAF are covered as well. The identification of specific molecular targets in a significant fraction of NSCLC has led to the personalized deployment of many effective targeted therapies, with more to come. PMID:25302162

Molecular targeted therapy for the treatment of gastric cancer.

PubMed

Xu, Wenting; Yang, Zhen; Lu, Nonghua

2016-01-04

Despite the global decline in the incidence and mortality of gastric cancer, it remains one of the most common malignant tumors of the digestive system. Although surgical resection is the preferred treatment for gastric cancer, chemotherapy is the preferred treatment for recurrent and advanced gastric cancer patients who are not candidates for reoperation. The short overall survival and lack of a standard chemotherapy regimen make it important to identify novel treatment modalities for gastric cancer. Within the field of tumor biology, molecular targeted therapy has attracted substantial attention to improve the specificity of anti-cancer efficacy and significantly reduce non-selective resistance and toxicity. Multiple clinical studies have confirmed that molecular targeted therapy acts on various mechanisms of gastric cancer, such as the regulation of epidermal growth factor, angiogenesis, immuno-checkpoint blockade, the cell cycle, cell apoptosis, key enzymes, c-Met, mTOR signaling and insulin-like growth factor receptors, to exert a stronger anti-tumor effect. An in-depth understanding of the mechanisms that underlie molecular targeted therapies will provide new insights into gastric cancer treatment.

Hepatoma targeting peptide conjugated bio-reducible polymer complexed with oncolytic adenovirus for cancer gene therapy.

PubMed

Choi, Joung-Woo; Kim, Hyun Ah; Nam, Kihoon; Na, Youjin; Yun, Chae-Ok; Kim, SungWan

2015-12-28

Despite adenovirus (Ad) vector's numerous advantages for cancer gene therapy, such as high ability of endosomal escape, efficient nuclear entry mechanism, and high transduction, and therapeutic efficacy, tumor specific targeting and antiviral immune response still remain as a critical challenge in clinical setting. To overcome these obstacles and achieve cancer-specific targeting, we constructed tumor targeting bioreducible polymer, an arginine grafted bio-reducible polymer (ABP)-PEG-HCBP1, by conjugating PEGylated ABP with HCBP1 peptides which has high affinity and selectivity towards hepatoma. The ABP-PEG-HCBP1-conjugated replication incompetent GFP-expressing ad, (Ad/GFP)-ABP-PEG-HCBP1, showed a hepatoma cancer specific uptake and transduction compared to either naked Ad/GFP or Ad/GFP-ABP. Competition assays demonstrated that Ad/GFP-ABP-PEG-HCBP1-mediated transduction was specifically inhibited by HCBP1 peptide rather than coxsackie and adenovirus receptor specific antibody. In addition, ABP-PEG-HCBP1 can protect biological activity of Ad against serum, and considerably reduced both innate and adaptive immune response against Ad. shMet-expressing oncolytic Ad (oAd; RdB/shMet) complexed with ABP-PEG-HCBP1 delivered oAd efficiently into hepatoma cancer cells. The oAd/ABP-PEG-HCBP1 demonstrated enhanced cancer cell killing efficacy in comparison to oAd/ABP complex. Furthermore, Huh7 and HT1080 cancer cells treated with oAd/shMet-ABP-PEG-HCBP1 complex had significantly decreased Met and VEGF expression in hepatoma cancer, but not in non-hepatoma cancer. In sum, these results suggest that HCBP1-conjugated bioreducible polymer could be used to deliver oncolytic Ad safely and efficiently to treat hepatoma. Copyright © 2015 Elsevier B.V. All rights reserved.

Bacteriophages and medical oncology: targeted gene therapy of cancer.

PubMed

Bakhshinejad, Babak; Karimi, Marzieh; Sadeghizadeh, Majid

2014-08-01

Targeted gene therapy of cancer is of paramount importance in medical oncology. Bacteriophages, viruses that specifically infect bacterial cells, offer a variety of potential applications in biomedicine. Their genetic flexibility to go under a variety of surface modifications serves as a basis for phage display methodology. These surface manipulations allow bacteriophages to be exploited for targeted delivery of therapeutic genes. Moreover, the excellent safety profile of these viruses paves the way for their potential use as cancer gene therapy platforms. The merge of phage display and combinatorial technology has led to the emergence of phage libraries turning phage display into a high throughput technology. Random peptide libraries, as one of the most frequently used phage libraries, provide a rich source of clinically useful peptide ligands. Peptides are known as a promising category of pharmaceutical agents in medical oncology that present advantages such as inexpensive synthesis, efficient tissue penetration and the lack of immunogenicity. Phage peptide libraries can be screened, through biopanning, against various targets including cancer cells and tissues that results in obtaining cancer-homing ligands. Cancer-specific peptides isolated from phage libraries show huge promise to be utilized for targeting of various gene therapy vectors towards malignant cells. Beyond doubt, bacteriophages will play a more impressive role in the future of medical oncology.

Targeting gene therapy to cancer: a review.

PubMed

Dachs, G U; Dougherty, G J; Stratford, I J; Chaplin, D J

1997-01-01

In recent years the idea of using gene therapy as a modality in the treatment of diseases other than genetically inherited, monogenic disorders has taken root. This is particularly obvious in the field of oncology where currently more than 100 clinical trials have been approved worldwide. This report will summarize some of the exciting progress that has recently been made with respect to both targeting the delivery of potentially therapeutic genes to tumor sites and regulating their expression within the tumor microenvironment. In order to specifically target malignant cells while at the same time sparing normal tissue, cancer gene therapy will need to combine highly selective gene delivery with highly specific gene expression, specific gene product activity, and, possibly, specific drug activation. Although the efficient delivery of DNA to tumor sites remains a formidable task, progress has been made in recent years using both viral (retrovirus, adenovirus, adeno-associated virus) and nonviral (liposomes, gene gun, injection) methods. In this report emphasis will be placed on targeted rather than high-efficiency delivery, although those would need to be combined in the future for effective therapy. To date delivery has been targeted to tumor-specific and tissue-specific antigens, such as epithelial growth factor receptor, c-kit receptor, and folate receptor, and these will be described in some detail. To increase specificity and safety of gene therapy further, the expression of the therapeutic gene needs to be tightly controlled within the target tissue. Targeted gene expression has been analyzed using tissue-specific promoters (breast-, prostate-, and melanoma-specific promoters) and disease-specific promoters (carcinoembryonic antigen, HER-2/neu, Myc-Max response elements, DF3/MUC). Alternatively, expression could be regulated externally with the use of radiation-induced promoters or tetracycline-responsive elements. Another novel possibility that will be

Practical issues of biomarker-assisted targeted therapy in precision medicine and immuno-oncology era.

PubMed

Lee, Dae Ho

2018-01-01

The concept of precision medicine is not new, as multiplex and very sensitive methods, or next-generation sequencing and matched targeted cancer therapies, have come to clinical practice. Substantial progress has been made from the discovery to the development and clinical application of biomarkers and matched targeted therapies. However, there still remain many challenges and issues to be overcome in each step, from acquisition of tumour tissues through validation of biomarkers to the final decision on targeted therapy. This review will briefly touch on these issues, hoping to provide a better understanding and application of targeted therapy in cancer treatment in the era of precision medicine and immuno-oncology. It also helps to understand that the meaning or value of biomarker(s) and matched targeted therapy changes along with expansion of knowledge and advance of methodology, and constant efforts have to be made in evaluating the meaning and clinical value during the development and after the establishment of biomarkers or the approval of matched targeted therapies, which might be more complicated by the advent of new therapeutic agents and new diagnostic methods.

Viral ancestors of antiviral systems.

PubMed

Villarreal, Luis P

2011-10-01

All life must survive their corresponding viruses. Thus antiviral systems are essential in all living organisms. Remnants of virus derived information are also found in all life forms but have historically been considered mostly as junk DNA. However, such virus derived information can strongly affect host susceptibility to viruses. In this review, I evaluate the role viruses have had in the origin and evolution of host antiviral systems. From Archaea through bacteria and from simple to complex eukaryotes I trace the viral components that became essential elements of antiviral immunity. I conclude with a reexamination of the 'Big Bang' theory for the emergence of the adaptive immune system in vertebrates by horizontal transfer and note how viruses could have and did provide crucial and coordinated features.

Advances in targeted therapy for acute myeloid leukaemia.

PubMed

Kayser, Sabine; Levis, Mark J

2018-02-01

In the past few years, research in the underlying pathogenic mechanisms of acute myeloid leukaemia (AML) has led to remarkable advances in our understanding of the disease. Cytogenetic and molecular aberrations are the most important factors in determining response to chemotherapy as well as long-term outcome, but beyond prognostication are potential therapeutic targets. Our increased understanding of the pathogenesis of AML, facilitated by next-generation sequencing, has spurred the development of new compounds in the treatment of AML, particularly the creation of small molecules that target the disease on a molecular level. Various new agents, such as tyrosine kinase inhibitors, immune checkpoint inhibitors, monoclonal or bispecific T-cell engager antibodies, metabolic and pro-apoptotic agents are currently investigated within clinical trials. The highest response rates are often achieved when new molecularly targeted therapies are combined with standard chemotherapy. Presented here is an overview of novel therapies currently being evaluated in AML. © 2017 John Wiley & Sons Ltd.

Folate-targeted nanoparticles for rheumatoid arthritis therapy.

PubMed

Nogueira, Eugénia; Gomes, Andreia C; Preto, Ana; Cavaco-Paulo, Artur

2016-05-01

Rheumatoid arthritis (RA) is the most common inflammatory rheumatic disease, affecting almost 1% of the world population. Although the cause of RA remains unknown, the complex interaction between immune mediators (cytokines and effector cells) is responsible for the joint damage that begins at the synovial membrane. Activated macrophages are critical in the pathogenesis of RA and showed specifically express a receptor for the vitamin folic acid (FA), folate receptor β (FRβ). This particular receptor allows internalization of FA-coupled cargo. In this review we will address the potential of nanoparticles as an effective drug delivery system for therapies that will directly target activated macrophages. Special attention will be given to stealth degree of the nanoparticles as a strategy to avoid clearance by macrophages of the mononuclear phagocytic system (MPS). This review summarizes the application of FA-target nanoparticles as drug delivery systems for RA and proposes prospective future directions. Rheumatoid arthritis is a debilitating autoimmune disease of the joints which affects many people worldwide. Up till now, there is a lack of optimal therapy against this disease. In this review article, the authors outlined in depth the current mechanism of disease for rheumatoid arthritis and described the latest research in using folic acid-targeted nanoparticles to target synovial macrophages in the fight against rheumatoid arthritis. Copyright © 2016 Elsevier Inc. All rights reserved.

A computational approach for predicting off-target toxicity of antiviral ribonucleoside analogues to mitochondrial RNA polymerase.

PubMed

Freedman, Holly; Winter, Philip; Tuszynski, Jack; Tyrrell, D Lorne; Houghton, Michael

2018-06-22

In the development of antiviral drugs that target viral RNA-dependent RNA polymerases, off-target toxicity caused by the inhibition of the human mitochondrial RNA polymerase (POLRMT) is a major liability. Therefore, it is essential that all new ribonucleoside analogue drugs be accurately screened for POLRMT inhibition. A computational tool that can accurately predict NTP binding to POLRMT could assist in evaluating any potential toxicity and in designing possible salvaging strategies. Using the available crystal structure of POLRMT bound to an RNA transcript, here we created a model of POLRMT with an NTP molecule bound in the active site. Furthermore, we implemented a computational screening procedure that determines the relative binding free energy of an NTP analogue to POLRMT by free energy perturbation (FEP), i.e. a simulation in which the natural NTP molecule is slowly transformed into the analogue and back. In each direction, the transformation was performed over 40 ns of simulation on our IBM Blue Gene Q supercomputer. This procedure was validated across a panel of drugs for which experimental dissociation constants were available, showing that NTP relative binding free energies could be predicted to within 0.97 kcal/mol of the experimental values on average. These results demonstrate for the first time that free-energy simulation can be a useful tool for predicting binding affinities of NTP analogues to a polymerase. We expect that our model, together with similar models of viral polymerases, will be very useful in the screening and future design of NTP inhibitors of viral polymerases that have no mitochondrial toxicity. © 2018 Freedman et al.

Antiviral therapy during primary simian immunodeficiency virus infection fails to prevent acute loss of CD4+ T cells in gut mucosa but enhances their rapid restoration through central memory T cells.

PubMed

Verhoeven, David; Sankaran, Sumathi; Silvey, Melanie; Dandekar, Satya

2008-04-01

Gut-associated lymphoid tissue (GALT) is an early target of human immunodeficiency virus (HIV) and simian immunodeficiency virus (SIV) and a site for severe CD4+ T-cell depletion. Although antiretroviral therapy (ART) is effective in suppressing HIV replication and restoring CD4+ T cells in peripheral blood, restoration in GALT is delayed. The role of restored CD4+ T-cell help in GALT during ART and its impact on antiviral CD8+ T-cell responses have not been investigated. Using the SIV model, we investigated gut CD4+ T-cell restoration in infected macaques, initiating ART during either the primary stage (1 week postinfection), prior to acute CD4+ cell loss (PSI), or during the chronic stage at 10 weeks postinfection (CSI). ART led to viral suppression in GALT and peripheral blood mononuclear cells of PSI and CSI animals at comparable levels. CSI animals had incomplete CD4+ T-cell restoration in GALT. In PSI animals, ART did not prevent acute CD4+ T-cell loss by 2 weeks postinfection in GALT but supported rapid and complete CD4+ T-cell restoration thereafter. This correlated with an accumulation of central memory CD4+ T cells and better suppression of inflammation. Restoration of CD4+ T cells in GALT correlated with qualitative changes in SIV gag-specific CD8+ T-cell responses, with a dominance of interleukin-2-producing responses in PSI animals, while both CSI macaques and untreated SIV-infected controls were dominated by gamma interferon responses. Thus, central memory CD4+ T-cell levels and qualitative antiviral CD8+ T-cell responses, independent of viral suppression, were the immune correlates of gut mucosal immune restoration during ART.

Hepatitis C virus in the new era: perspectives in epidemiology, prevention, diagnostics and predictors of response to therapy.

PubMed

Ansaldi, Filippo; Orsi, Andrea; Sticchi, Laura; Bruzzone, Bianca; Icardi, Giancarlo

2014-08-07

Despite the great successes achieved in the fields of virology and diagnostics, several difficulties affect improvements in hepatitis C virus (HCV) infection control and eradication in the new era. New HCV infections still occur, especially in some of the poorest regions of the world, where HCV is endemic and long-term sequelae have a growing economic and health burden. An HCV vaccine is still no available, despite years of researches and discoveries about the natural history of infection and host-virus interactions: several HCV vaccine candidates have been developed in the last years, targeting different HCV antigens or using alternative delivery systems, but viral variability and adaption ability constitute major challenges for vaccine development. Many new antiviral drugs for HCV therapy are in preclinical or early clinical development, but different limitations affect treatment validity. Treatment predictors are important tools, as they provide some guidance for the management of therapy in patients with chronic HCV infection: in particular, the role of host genomics in HCV infection outcomes in the new era of direct-acting antivirals may evolve for new therapeutic targets, representing a chance for modulated and personalized treatment management, when also very potent therapies will be available. In the present review we discuss the most recent data about HCV epidemiology, the new perspectives for the prevention of HCV infection and the most recent evidence regarding HCV diagnosis, therapy and predictors of response to it.

Antiviral activity of silymarin against chikungunya virus

PubMed Central

Lani, Rafidah; Hassandarvish, Pouya; Chiam, Chun Wei; Moghaddam, Ehsan; Chu, Justin Jang Hann; Rausalu, Kai; Merits, Andres; Higgs, Stephen; Vanlandingham, Dana; Abu Bakar, Sazaly; Zandi, Keivan

2015-01-01

The mosquito-borne chikungunya virus (CHIKV) causes chikungunya fever, with clinical presentations such as severe back and small joint pain, and debilitating arthritis associated with crippling pains that persist for weeks and even years. Although there are several studies to evaluate the efficacy of drugs against CHIKV, the treatment for chikungunya fever is mainly symptom-based and no effective licensed vaccine or antiviral are available. Here, we investigated the antiviral activity of three types of flavonoids against CHIKV in vitro replication. Three compounds: silymarin, quercetin and kaempferol were evaluated for their in vitro antiviral activities against CHIKV using a CHIKV replicon cell line and clinical isolate of CHIKV of Central/East African genotype. A cytopathic effect inhibition assay was used to determine their activities on CHIKV viral replication and quantitative reverse transcription PCR was used to calculate virus yield. Antiviral activity of effective compound was further investigated by evaluation of CHIKV protein expression using western blotting for CHIKV nsP1, nsP3, and E2E1 proteins. Briefly, silymarin exhibited significant antiviral activity against CHIKV, reducing both CHIKV replication efficiency and down-regulating production of viral proteins involved in replication. This study may have important consequence for broaden the chance of getting the effective antiviral for CHIKV infection. PMID:26078201

Virus-Based Cancer Therapeutics for Targeted Photodynamic Therapy.

PubMed

Cao, Binrui; Xu, Hong; Yang, Mingying; Mao, Chuanbin

2018-01-01

Cancer photodynamic therapy (PDT) involves the absorption of light by photosensitizers (PSs) to generate cytotoxic singlet oxygen for killing cancer cells. The success of this method is usually limited by the lack of selective accumulation of the PS at cancer cells. Bioengineered viruses with cancer cell-targeting peptides fused on their surfaces are great drug carriers that can guide the PS to cancer cells for targeted cancer treatment. Here, we use cell-targeting fd bacteriophages (phages) as an example to describe how to chemically conjugate PSs (e.g., pyropheophorbide-a (PPa)) onto a phage particle to achieve targeted PDT.

Anti-E1E2 antibodies status prior therapy favors direct-acting antiviral treatment efficacy.

PubMed

Virlogeux, Victor; Berthillon, Pascale; Bordes, Isabelle; Larrat, Sylvie; Crouy, Stéphanie; Scholtès, Caroline; Pradat, Pierre; Maynard, Marianne; Zoulim, Fabien; Leroy, Vincent; Chemin, Isabelle; Trépo, Christian; Petit, Marie-Anne

2018-03-15

Presence of anti-E1E2 antibodies was previously associated with spontaneous cure of hepatitis C virus (HCV) and predictive before treatment of a sustained virological response (SVR) to bi- or tri-therapy in naïve or experienced patients, regardless of HCV genotype. We investigated the impact of anti-E1E2 seroprevalence at baseline on treatment response in patients receiving direct-acting antiviral (DAA) therapy. We screened anti-E1E2 antibodies by ELISA in serum samples collected at treatment initiation for two groups of patients: 59 with SVR at the end of DAA treatment and 44 relapsers after DAA treatment. Nineteen patients received a combination of ribavirin (RBV) or PEG-interferon/ribavirin with sofosbuvir or daclatasvir and others received interferon-free treatment with DAA±RBV. HCV viral load was measured at different time points during treatment in a subgroup of patients. A significant association was observed between presence of anti-E1E2 and HCV viral load<6log10 prior treatment. Among patients with anti-E1E2 at baseline, 70% achieved SVR whereas among patients without anti-E1E2, only 45% achieved SVR. Conversely, 66% of patients experiencing DAA-failure were anti-E1E2 negative at baseline. In the multivariate analysis, presence of anti-E1E2 was significantly associated with SVR after adjustment on potential cofounders such as age, sex, fibrosis stage, prior HCV treatment and alanine aminotransferase (ALT) level. The presence of anti-E1E2 at treatment initiation is a predictive factor of SVR among patients treated with DAA and more likely among patients with low initial HCV viral load (<6log10). Absence of anti-E1E2 at baseline could predict DAA-treatment failure. Copyright © 2018 Elsevier Masson SAS. All rights reserved.

Antiviral agents for infectious mononucleosis (glandular fever).

PubMed

De Paor, Muireann; O'Brien, Kirsty; Fahey, Tom; Smith, Susan M

2016-12-08

Infectious mononucleosis (IM) is a clinical syndrome, usually caused by the Epstein Barr virus (EPV), characterised by lymphadenopathy, fever and sore throat. Most cases of symptomatic IM occur in older teenagers or young adults. Usually IM is a benign self-limiting illness and requires only symptomatic treatment. However, occasionally the disease course can be complicated or prolonged and lead to decreased productivity in terms of school or work. Antiviral medications have been used to treat IM, but the use of antivirals for IM is controversial. They may be effective by preventing viral replication which helps to keep the virus inactive. However, there are no guidelines for antivirals in IM. To assess the effects of antiviral therapy for infectious mononucleosis (IM). We searched the Cochrane Central Register of Controlled Trials (CENTRAL, Issue 3, March 2016), which contains the Cochrane Acute Respiratory Infections (ARI) Group's Specialised Register, MEDLINE (1946 to 15 April 2016), Embase (1974 to 15 April 2016), CINAHL (1981 to 15 April 2016), LILACS (1982 to 15 April 2016) and Web of Science (1955 to 15 April 2016). We searched the World Health Organization (WHO) International Clinical Trials Registry Platform and ClinicalTrials.gov for completed and ongoing trials. We included randomised controlled trials (RCTs) comparing antivirals versus placebo or no treatment in IM. We included trials of immunocompetent participants of any age or sex with clinical and laboratory-confirmed diagnosis of IM, who had symptoms for up to 14 days. Our primary outcomes were time to clinical recovery and adverse events and side effects of medication. Secondary outcomes included duration of abnormal clinical examination, complications, viral shedding, health-related quality of life, days missing from school or work and economic outcomes. Two review authors independently assessed studies for inclusion, assessed the included studies' risk of bias and extracted data using a

Targeted therapy using nanotechnology: focus on cancer

PubMed Central

Sanna, Vanna; Pala, Nicolino; Sechi, Mario

2014-01-01

Recent advances in nanotechnology and biotechnology have contributed to the development of engineered nanoscale materials as innovative prototypes to be used for biomedical applications and optimized therapy. Due to their unique features, including a large surface area, structural properties, and a long circulation time in blood compared with small molecules, a plethora of nanomaterials has been developed, with the potential to revolutionize the diagnosis and treatment of several diseases, in particular by improving the sensitivity and recognition ability of imaging contrast agents and by selectively directing bioactive agents to biological targets. Focusing on cancer, promising nanoprototypes have been designed to overcome the lack of specificity of conventional chemotherapeutic agents, as well as for early detection of precancerous and malignant lesions. However, several obstacles, including difficulty in achieving the optimal combination of physicochemical parameters for tumor targeting, evading particle clearance mechanisms, and controlling drug release, prevent the translation of nanomedicines into therapy. In spite of this, recent efforts have been focused on developing functionalized nanoparticles for delivery of therapeutic agents to specific molecular targets overexpressed on different cancer cells. In particular, the combination of targeted and controlled-release polymer nanotechnologies has resulted in a new programmable nanotherapeutic formulation of docetaxel, namely BIND-014, which recently entered Phase II clinical testing for patients with solid tumors. BIND-014 has been developed to overcome the limitations facing delivery of nanoparticles to many neoplasms, and represents a validated example of targeted nanosystems with the optimal biophysicochemical properties needed for successful tumor eradication. PMID:24531078

Targeted Drug and Gene Delivery Systems for Lung Cancer Therapy

PubMed Central

Sundaram, Sneha; Trivedi, Ruchit; Durairaj, Chandrasekar; Ramesh, Rajagopal; Ambati, Balamurali K.; Kompella, Uday B.

2009-01-01

Purpose To evaluate the efficacy of a novel docetaxel derivative of deslorelin, a luteinizing hormone releasing hormone (LHRH) agonist, and its combination in-vivo with RGD peptide conjugated nanoparticles encapsulating an anti-angiogenic, anti-VEGF intraceptor (Flt23k) (RGD-Flt23k-NP) in H1299 lung cancer cells and/or xenografts in athymic nude BALB/c mice. Experimental Design The in-vitro and in-vivo efficacy of the deslorelin-docetaxel conjugate (D-D) was evaluated in H1299 cells and xenografts in athymic nude mice. Co-administration of D-D and RGD-Flt23k-NP was tested in-vivo in mice. Tumor inhibition, apoptosis and VEGF inhibition were estimated in each of the treatment groups. Results The conjugate enhanced in-vitro docetaxel efficacy by 13-fold in H1299 cells compared to docetaxel at 24h, and this effect was inhibited following reduction of LHRH-receptor expression by an antisense oligonucleotide. Combination of the conjugate with the RGD-Flt23k-NP in-vivo resulted in an 82- and 15-fold tumor growth inhibition on day 39 following repeated weekly intravenous injections and a single intratumoral injection, respectively. These effects were significantly greater than individual targeted therapies or docetaxel alone. Similarly, apoptotic indices for the combination therapy were 14 and 10% in the intravenous and intratumoral groups, respectively, and higher than the individual therapies. Combination therapy groups exhibited greater VEGF inhibition in both the intravenous and intratumoral groups. Conclusions Docetaxel efficacy was enhanced by LHRH-receptor targeted deslorelin conjugate and further improved by combination with targeted anti-angiogenic nanoparticle gene therapy. Combination of novel targeted therapeutic approaches described here provides an attractive alternative to the current treatment options for lung cancer therapy. PMID:19920099

A small molecule nanodrug consisting of amphiphilic targeting ligand-chemotherapy drug conjugate for targeted cancer therapy.

PubMed

Mou, Quanbing; Ma, Yuan; Zhu, Xinyuan; Yan, Deyue

2016-05-28

Targeted drug delivery is a broadly applicable approach for cancer therapy. However, the nanocarrier-based targeted delivery system suffers from batch-to-batch variation, quality concerns and carrier-related toxicity issues. Thus, to develop a carrier-free targeted delivery system with nanoscale characteristics is very attractive. Here, a novel targeting small molecule nanodrug self-delivery system consisting of targeting ligand and chemotherapy drug was constructed, which combined the advantages of small molecules and nano-assemblies together and showed excellent targeting ability and long blood circulation time with well-defined structure, high drug loading ratio and on-demand drug release behavior. As a proof-of-concept, lactose (Lac) and doxorubicin (DOX) were chosen as the targeting ligand and chemotherapy drug, respectively. Lac and DOX were conjugated through a pH-responsive hydrazone group. For its intrinsic amphiphilic property, Lac-DOX conjugate could self-assemble into nanoparticles in water. Both in vitro and in vivo assays indicated that Lac-DOX nanoparticles exhibited enhanced anticancer activity and weak side effects. This novel active targeting nanodrug delivery system shows great potential in cancer therapy. Copyright © 2016 Elsevier B.V. All rights reserved.

Current therapies and targets for type 2 diabetes mellitus: a review.

PubMed

Chellapan, Dinesh K; Sheng Yap, Wei; Bt Ahmad Suhaimi, Nurfatihah A; Gupta, Gaurav; Dua, Kamal

2018-04-24

The prevalence of type 2 diabetes mellitus (T2DM) has been increasing at an alarming rate. With an increased understanding of the pathophysiology and pathogenesis of T2DM, various new therapeutic options have been developed to target different key defects in T2DM. Incremental innovations of existing therapies either through unprecedented drug combinations, modified drug molecules, or improved delivery systems are capable to nullify some of the undesirable side effects of traditional therapies as well as to enhance effectiveness. The existing administration routes include inhalation, nasal, buccal, parenteral and oral. Newer drug targets such as protein kinase B (Akt/PKB), AMPactivated protein kinase (AMPK), sirtuin (SIRT), and others are novel approaches that act via different mechanisms and possibly treating T2DM of distinct variations and aetiologies. Other therapies such as endobarrier, gene therapy, and stem cell technology utilize advanced techniques to treat T2DM, and the potential of these therapies are still being explored. Gene therapy is plausible to fix the underlying pathology of T2DM instead of using traditional reactive treatments, especially with the debut of Clustered Regularly Interspaced Short Palindromic RepeatsCRISPR associated protein9 (CRISPRCas9) gene editing tool. Molecular targets in T2DM are also being extensively studied as it could target the defects at the molecular level. Furthermore, antibody therapies and vaccinations are also being developed against T2DM; but the ongoing clinical trials are relatively lesser and the developmental progress is slower. Although, there are many therapies designed to cure T2DM, each of them has their own advantages and disadvantages. The preference for the treatment plan usually depends on the health status of the patient and the treatment goal. Therefore, an ideal treatment should take patient's compliance, efficacy, potency, bioavailability, and other pharmacological and nonpharmacological properties

The roles of pathology in targeted therapy of women with gynecologic cancers.

PubMed

Murali, Rajmohan; Grisham, Rachel N; Soslow, Robert A

2018-01-01

The role of the pathologist in the multidisciplinary management of women with gynecologic cancer has evolved substantially over the past decade. Pathologists' evaluation of parameters such as pathologic stage, histologic subtype, grade and microsatellite instability, and their identification of patients at risk for Lynch syndrome have become essential components of diagnosis, prognostic assessment and determination of optimal treatment of affected women. Despite the use of multimodality treatment and combination cytotoxic chemotherapy, the prognosis of women with advanced-stage gynecologic cancer is often poor. Therefore, expanding the arsenal of available systemic therapies with targeted therapeutic agents is appealing. Anti-angiogenic therapies, immunotherapy and poly ADP ribose polymerase (PARP) inhibitors are now routinely used for the treatment of advanced gynecologic cancer, and many more are under investigation. Pathologists remain important in the clinical management of patients with targeted therapy, by identifying potentially targetable tumors on the basis of their pathologic phenotype, by assessing biomarkers that are predictive of response to targeted therapy (e.g. microsatellite instability, PD1/PDL1 expression), and by monitoring treatment response and resistance. Pathologists are also vital to research efforts exploring novel targeted therapies by identifying homogenous subsets of tumors for more reliable and meaningful analyses, and by confirming expression in tumor tissues of novel targets identified in genomic, epigenetic or other screening studies. In the era of precision gynecologic oncology, the roles of pathologists in the discovery, development and implementation of targeted therapeutic strategies remain as central as they are for traditional (surgery-chemotherapy-radiotherapy) management of women with gynecologic cancers. Copyright © 2017 Elsevier Inc. All rights reserved.

New Molecular Targets of Anticancer Therapy - Current Status and Perspectives.

PubMed

Zajac, Marianna; Muszalska, Izabela; Jelinska, Anna

2016-01-01

Molecularly targeted anticancer therapy involves the use of drugs or other substances affecting specific molecular targets that play a part in the development, progression and spread of a given neoplasm. By contrast, the majority of classical chemotherapeutics act on all rapidly proliferating cells, both healthy and cancerous ones. Target anticancer drugs are designed to achieve a particular aim and they usually act cytostatically, not cytotoxically like classical chemotherapeutics. At present, more than 300 biological molecular targets have been identified. The proteins involved in cellular metabolism include (among others) receptor proteins, signal transduction proteins, mRNA thread matrix synthesis proteins participating in neoplastic transformation, cell cycle control proteins, functional and structural proteins. The receptor proteins that are targeted by currently used anticancer drugs comprise the epithelial growth factor receptor (EGFR), platelet-derived growth factor receptor (PDGFR) and vascular endothelial growth factor receptor(VEGFR). Target anticancer drugs may affect extracellular receptor domains (antibodies) or intracellular receptor domains (tyrosine kinase inhibitors). The blocking of the mRNA thread containing information about the structure of oncogenes (signal transduction proteins) is another molecular target of anticancer drugs. That type of treatment, referred to as antisense therapy, is in clinical trials. When the synthesis of genetic material is disturbed, in most cases the passage to the next cycle phase is blocked. The key proteins responsible for the blockage are cyclines and cycline- dependent kinases (CDK). Clinical trials are focused on natural and synthetic substances capable of blocking various CDKs. The paper discusses the molecular targets and chemical structure of target anticancer drugs that have been approved for and currently applied in antineoplastic therapy together with indications and contraindications for their

Financial relationships in economic analyses of targeted therapies in oncology.

PubMed

Valachis, Antonis; Polyzos, Nikolaos P; Nearchou, Andreas; Lind, Pehr; Mauri, Davide

2012-04-20

A potential financial relationship between investigators and pharmaceutical manufacturers has been associated with an increased likelihood of reporting favorable conclusions about a sponsor's proprietary agent in pharmacoeconomic studies. The purpose of this study is to investigate whether there is an association between financial relationships and outcome in economic analyses of new targeted therapies in oncology. We searched PubMed (last update June 2011) for economic analyses of targeted therapies (including monoclonal antibodies, tyrosine-kinase inhibitors, and mammalian target of rapamycin inhibitors) in oncology. The trials were qualitatively rated regarding the cost assessment as favorable, neutral, or unfavorable on the basis of prespecified criteria. Overall, 81 eligible studies were identified. Economic analyses that were funded by pharmaceutical companies were more likely to report favorable qualitative cost estimates (28 [82%] of 34 v 21 [45%] of 47; P = .003). The presence of an author affiliated with manufacturer was not associated with study outcome. Furthermore, if only studies including a conflict of interest statement were included (66 of 81), studies that reported any financial relationship with manufacturers (author affiliation and/or funding and/or other financial relationship) were more likely to report favorable results of targeted therapies compared with studies without financial relationship (32 [71%] of 45 v nine [43%] of 21; P = .025). Our study reveals a potential threat for industry-related bias in economic analyses of targeted therapies in oncology in favor of analyses with financial relationships between authors and manufacturers. A more balanced funding of economic analyses from other sources may allow greater confidence in the interpretation of their results.

Antiviral Drug Research Proposal Activity †

PubMed Central

Injaian, Lisa; Smith, Ann C.; Shipley, Jennifer German; Marbach-Ad, Gili; Fredericksen, Brenda

2011-01-01

The development of antiviral drugs provides an excellent example of how basic and clinical research must be used together in order to achieve the final goal of treating disease. A Research Oriented Learning Activity was designed to help students to better understand how basic and clinical research can be combined toward a common goal. Through this project students gained a better understanding of the process of scientific research and increased their information literacy in the field of virology. The students worked as teams to research the many aspects involved in the antiviral drug design process, with each student becoming an “expert” in one aspect of the project. The Antiviral Drug Research Proposal (ADRP) culminated with students presenting their proposals to their peers and local virologists in a poster session. Assessment data showed increased student awareness and knowledge of the research process and the steps involved in the development of antiviral drugs as a result of this activity. PMID:23653735

A cMUT probe for ultrasound-guided focused ultrasound targeted therapy.

PubMed

Gross, Dominique; Coutier, Caroline; Legros, Mathieu; Bouakaz, Ayache; Certon, Dominique

2015-06-01

Ultrasound-mediated targeted therapy represents a promising strategy in the arsenal of modern therapy. Capacitive micromachined ultrasonic transducer (cMUT) technology could overcome some difficulties encountered by traditional piezoelectric transducers. In this study, we report on the design, fabrication, and characterization of an ultrasound-guided focused ultrasound (USgFUS) cMUT probe dedicated to preclinical evaluation of targeted therapy (hyperthermia, thermosensitive liposomes activation, and sonoporation) at low frequency (1 MHz) with simultaneous ultrasonic imaging and guidance (15 to 20 MHz). The probe embeds two types of cMUT arrays to perform the modalities of targeted therapy and imaging respectively. The wafer-bonding process flow employed for the manufacturing of the cMUTs is reported. One of its main features is the possibility of implementing two different gap heights on the same wafer. All the design and characterization steps of the devices are described and discussed, starting from the array design up to the first in vitro measurements: optical (microscopy) and electrical (impedance) measurements, arrays' electroacoustic responses, focused pressure field mapping (maximum peak-to-peak pressure = 2.5 MPa), and the first B-scan image of a wire-target phantom.

Viral Ancestors of Antiviral Systems

PubMed Central

Villarreal, Luis P.

2011-01-01

All life must survive their corresponding viruses. Thus antiviral systems are essential in all living organisms. Remnants of virus derived information are also found in all life forms but have historically been considered mostly as junk DNA. However, such virus derived information can strongly affect host susceptibility to viruses. In this review, I evaluate the role viruses have had in the origin and evolution of host antiviral systems. From Archaea through bacteria and from simple to complex eukaryotes I trace the viral components that became essential elements of antiviral immunity. I conclude with a reexamination of the ‘Big Bang’ theory for the emergence of the adaptive immune system in vertebrates by horizontal transfer and note how viruses could have and did provide crucial and coordinated features. PMID:22069523

The benefits of steroids versus steroids plus antivirals for treatment of Bell's palsy: a meta-analysis.

PubMed

Quant, Eudocia C; Jeste, Shafali S; Muni, Rajeev H; Cape, Alison V; Bhussar, Manveen K; Peleg, Anton Y

2009-09-07

Bell's palsy. This study does not, therefore, support the routine use of antivirals in Bell's palsy. Future studies should use improved herpes virus diagnostics and newer antivirals to assess whether combination therapy benefits patients with more severe facial paralysis at study entry.

Cancer Nanotheranostics: Improving Imaging and Therapy by Targeted Delivery across Biological Barriers

PubMed Central

Kievit, Forrest M.; Zhang, Miqin

2012-01-01

Cancer nanotheranostics aims to combine imaging and therapy of cancer through use of nanotechnology. The ability to engineer nanomaterials to interact with cancer cells at the molecular level can significantly improve the effectiveness and specificity of therapy to cancers that are currently difficult to treat. In particular, metastatic cancers, drug-resistant cancers, and cancer stem cells impose the greatest therapeutic challenge that requires targeted therapy to treat effectively. Targeted therapy can be achieved with appropriate designed drug delivery vehicles such as nanoparticles, adult stem cells, or T cells in immunotherapy. In this article, we first review the different types of materials commonly used to synthesize nanotheranostic particles and their use in imaging. We then discuss biological barriers that these nanoparticles encounter and must bypass to reach the target cancer cells, including the blood, liver, kidneys, spleen, and particularly the blood-brain barrier. We then review how nanotheranostics can be used to improve targeted delivery and treatment of cancer cells using nanoparticles, adult stem cells, and T cells in immunotherapy. Finally, we discuss development of nanoparticles to overcome current limitations in cancer therapy. PMID:21842473

Optimizing Tactics for Use of the U.S. Antiviral Strategic National Stockpile for Pandemic Influenza

PubMed Central

Dimitrov, Nedialko B.; Goll, Sebastian; Hupert, Nathaniel; Pourbohloul, Babak; Meyers, Lauren Ancel

2011-01-01

In 2009, public health agencies across the globe worked to mitigate the impact of the swine-origin influenza A (pH1N1) virus. These efforts included intensified surveillance, social distancing, hygiene measures, and the targeted use of antiviral medications to prevent infection (prophylaxis). In addition, aggressive antiviral treatment was recommended for certain patient subgroups to reduce the severity and duration of symptoms. To assist States and other localities meet these needs, the U.S. Government distributed a quarter of the antiviral medications in the Strategic National Stockpile within weeks of the pandemic's start. However, there are no quantitative models guiding the geo-temporal distribution of the remainder of the Stockpile in relation to pandemic spread or severity. We present a tactical optimization model for distributing this stockpile for treatment of infected cases during the early stages of a pandemic like 2009 pH1N1, prior to the wide availability of a strain-specific vaccine. Our optimization method efficiently searches large sets of intervention strategies applied to a stochastic network model of pandemic influenza transmission within and among U.S. cities. The resulting optimized strategies depend on the transmissability of the virus and postulated rates of antiviral uptake and wastage (through misallocation or loss). Our results suggest that an aggressive community-based antiviral treatment strategy involving early, widespread, pro-rata distribution of antivirals to States can contribute to slowing the transmission of mildly transmissible strains, like pH1N1. For more highly transmissible strains, outcomes of antiviral use are more heavily impacted by choice of distribution intervals, quantities per shipment, and timing of shipments in relation to pandemic spread. This study supports previous modeling results suggesting that appropriate antiviral treatment may be an effective mitigation strategy during the early stages of future influenza

Viral infection and antiviral therapy in the neonatal intensive care unit.

PubMed

Barford, Galina; Rentz, Alison C; Faix, Roger G

2004-01-01

Viral diseases are leading causes of mortality and morbidity among infants requiring care in the neonatal intensive care unit (NICU), with ongoing discoveries of new viral pathology likely to add to the burdens posed. Many viral diseases in NICU infants are undiagnosed or appreciated only late in the course because of subtle or asymptomatic presentation, confusion with bacterial disease, and failure to consider viral disease. We present an overview of viral disease in NICU infants, with emphasis on pharmacologic agents currently employed for prophylaxis and treatment of such diseases. Advances in molecular biology and popular demand to develop antiviral agents for viral diseases (eg, human immunodeficiency virus) offer great promise for the future.

Genetic heterogeneity in cholangiocarcinoma: a major challenge for targeted therapies

PubMed Central

Brandi, Giovanni; Farioli, Andrea; Astolfi, Annalisa; Biasco, Guido; Tavolari, Simona

2015-01-01

Cholangiocarcinoma (CC) encompasses a group of related but distinct malignancies whose lack of a stereotyped genetic signature makes challenging the identification of genomic landscape and the development of effective targeted therapies. Accumulated evidences strongly suggest that the remarkable genetic heterogeneity of CC may be the result of a complex interplay among different causative factors, some shared by most human cancers while others typical of this malignancy. Currently, considerable efforts are ongoing worldwide for the genetic characterization of CC, also using advanced technologies such as next-generation sequencing (NGS). Undoubtedly this technology could offer an unique opportunity to broaden our understanding on CC molecular pathogenesis. Despite this great potential, however, the high complexity in terms of factors potentially contributing to genetic variability in CC calls for a more cautionary application of NGS to this malignancy, in order to avoid possible biases and criticisms in the identification of candidate actionable targets. This approach is further justified by the urgent need to develop effective targeted therapies in this disease. A multidisciplinary approach integrating genomic, functional and clinical studies is therefore mandatory to translate the results obtained by NGS into effective targeted therapies for this orphan disease. PMID:26142706

Systems biology: A tool for charting the antiviral landscape.

PubMed

Bowen, James R; Ferris, Martin T; Suthar, Mehul S

2016-06-15

The host antiviral programs that are initiated following viral infection form a dynamic and complex web of responses that we have collectively termed as "the antiviral landscape". Conventional approaches to studying antiviral responses have primarily used reductionist systems to assess the function of a single or a limited subset of molecules. Systems biology is a holistic approach that considers the entire system as a whole, rather than individual components or molecules. Systems biology based approaches facilitate an unbiased and comprehensive analysis of the antiviral landscape, while allowing for the discovery of emergent properties that are missed by conventional approaches. The antiviral landscape can be viewed as a hierarchy of complexity, beginning at the whole organism level and progressing downward to isolated tissues, populations of cells, and single cells. In this review, we will discuss how systems biology has been applied to better understand the antiviral landscape at each of these layers. At the organismal level, the Collaborative Cross is an invaluable genetic resource for assessing how genetic diversity influences the antiviral response. Whole tissue and isolated bulk cell transcriptomics serves as a critical tool for the comprehensive analysis of antiviral responses at both the tissue and cellular levels of complexity. Finally, new techniques in single cell analysis are emerging tools that will revolutionize our understanding of how individual cells within a bulk infected cell population contribute to the overall antiviral landscape. Copyright © 2016 Elsevier B.V. All rights reserved.

Drug-targeting strategies in cancer therapy.

PubMed

Huang, P S; Oliff, A

2001-02-01

Genetic changes in cell-cycle, apoptotic, and survival pathways cause tumorigenesis, leading to significant phenotypic changes in transformed cells. These changes in the tumor environment - elevated expression of surface proteases, increased angiogenesis and glucuronidase activity - can be taken advantage of to improve the therapeutic index of existing cancer therapies. Targeting cytotoxics to tumor cells by enzymatic activation is a promising strategy for improving chemotherapeutics.

Targeting Strategies for Multifunctional Nanoparticles in Cancer Imaging and Therapy

PubMed Central

Yu, Mi Kyung; Park, Jinho; Jon, Sangyong

2012-01-01

Nanomaterials offer new opportunities for cancer diagnosis and treatment. Multifunctional nanoparticles harboring various functions including targeting, imaging, therapy, and etc have been intensively studied aiming to overcome limitations associated with conventional cancer diagnosis and therapy. Of various nanoparticles, magnetic iron oxide nanoparticles with superparamagnetic property have shown potential as multifunctional nanoparticles for clinical translation because they have been used asmagnetic resonance imaging (MRI) constrast agents in clinic and their features could be easily tailored by including targeting moieties, fluorescence dyes, or therapeutic agents. This review summarizes targeting strategies for construction of multifunctional nanoparticles including magnetic nanoparticles-based theranostic systems, and the various surface engineering strategies of nanoparticles for in vivo applications. PMID:22272217

Crystal structure of an antiviral ankyrin targeting the HIV-1 capsid and molecular modeling of the ankyrin-capsid complex.

PubMed

Praditwongwan, Warachai; Chuankhayan, Phimonphan; Saoin, Somphot; Wisitponchai, Tanchanok; Lee, Vannajan Sanghiran; Nangola, Sawitree; Hong, Saw See; Minard, Philippe; Boulanger, Pierre; Chen, Chun-Jung; Tayapiwatana, Chatchai

2014-08-01

Ankyrins are cellular repeat proteins, which can be genetically modified to randomize amino-acid residues located at defined positions in each repeat unit, and thus create a potential binding surface adaptable to macromolecular ligands. From a phage-display library of artificial ankyrins, we have isolated Ank(GAG)1D4, a trimodular ankyrin which binds to the HIV-1 capsid protein N-terminal domain (NTD(CA)) and has an antiviral effect at the late steps of the virus life cycle. In this study, the determinants of the Ank(GAG)1D4-NTD(CA) interaction were analyzed using peptide scanning in competition ELISA, capsid mutagenesis, ankyrin crystallography and molecular modeling. We determined the Ank(GAG)1D4 structure at 2.2 Å resolution, and used the crystal structure in molecular docking with a homology model of HIV-1 capsid. Our results indicated that NTD(CA) alpha-helices H1 and H7 could mediate the formation of the capsid-Ank(GAG)1D4 binary complex, but the interaction involving H7 was predicted to be more stable than with H1. Arginine-18 (R18) in H1, and R132 and R143 in H7 were found to be the key players of the Ank(GAG)1D4-NTD(CA) interaction. This was confirmed by R-to-A mutagenesis of NTD(CA), and by sequence analysis of trimodular ankyrins negative for capsid binding. In Ank(GAG)1D4, major interactors common to H1 and H7 were found to be S45, Y56, R89, K122 and K123. Collectively, our ankyrin-capsid binding analysis implied a significant degree of flexibility within the NTD(CA) domain of the HIV-1 capsid protein, and provided some clues for the design of new antivirals targeting the capsid protein and viral assembly.

Crystal structure of an antiviral ankyrin targeting the HIV-1 capsid and molecular modeling of the ankyrin-capsid complex

NASA Astrophysics Data System (ADS)

Praditwongwan, Warachai; Chuankhayan, Phimonphan; Saoin, Somphot; Wisitponchai, Tanchanok; Lee, Vannajan Sanghiran; Nangola, Sawitree; Hong, Saw See; Minard, Philippe; Boulanger, Pierre; Chen, Chun-Jung; Tayapiwatana, Chatchai

2014-08-01

Ankyrins are cellular repeat proteins, which can be genetically modified to randomize amino-acid residues located at defined positions in each repeat unit, and thus create a potential binding surface adaptable to macromolecular ligands. From a phage-display library of artificial ankyrins, we have isolated AnkGAG1D4, a trimodular ankyrin which binds to the HIV-1 capsid protein N-terminal domain (NTDCA) and has an antiviral effect at the late steps of the virus life cycle. In this study, the determinants of the AnkGAG1D4-NTDCA interaction were analyzed using peptide scanning in competition ELISA, capsid mutagenesis, ankyrin crystallography and molecular modeling. We determined the AnkGAG1D4 structure at 2.2 Å resolution, and used the crystal structure in molecular docking with a homology model of HIV-1 capsid. Our results indicated that NTDCA alpha-helices H1 and H7 could mediate the formation of the capsid-AnkGAG1D4 binary complex, but the interaction involving H7 was predicted to be more stable than with H1. Arginine-18 (R18) in H1, and R132 and R143 in H7 were found to be the key players of the AnkGAG1D4-NTDCA interaction. This was confirmed by R-to-A mutagenesis of NTDCA, and by sequence analysis of trimodular ankyrins negative for capsid binding. In AnkGAG1D4, major interactors common to H1 and H7 were found to be S45, Y56, R89, K122 and K123. Collectively, our ankyrin-capsid binding analysis implied a significant degree of flexibility within the NTDCA domain of the HIV-1 capsid protein, and provided some clues for the design of new antivirals targeting the capsid protein and viral assembly.

[Targeted therapies in hepatocellular carcinomas: recent results and future development].

PubMed

Marijon, H; Faivre, S; Raymond, E

2009-05-01

Hepatocellular carcinoma (HCC) is one of the 5th most common cancers around the world with a limited number of systemic therapeutic options. Cytotoxic agents, hormonotherapy and immunotherapy have failed to demonstrate benefit compared to best supportive care in patients with advanced HCC. The recent development of targeted therapies provided hope for the treatment of advanced HCC. We reviewed phases II-III trials presented in 2007 and 2008. Results are promising with a clinical benefit reported with molecular therapies targeting EGF/EGFR and VEGF/VEGFR pathways.

Week 4 response predicts sustained virological response to all-oral direct-acting antiviral-based therapy in cirrhotic patients with hepatitis C virus genotype 3 infection.

PubMed

Pineda, J A; Morano-Amado, L E; Granados, R; Macías, J; Téllez, F; García-Deltoro, M; Ríos, M J; Collado, A; Delgado-Fernández, M; Suárez-Santamaría, M; Serrano, M; Miralles-Álvarez, C; Neukam, K

2017-06-01

The aim of this study was to determine the predictive capacity of response at treatment week (TW) 4 for the achievement of sustained virological response 12 weeks after the scheduled end of therapy date (SVR 12 ) to treatment against hepatitis C virus (HCV) genotype 3 (GT3) infection with all-oral direct-acting antiviral (DAA) -based regimens. From a prospective multicohort study, HCV GT3-infected patients who completed a course of currently recommended DAA-based therapy at 33 Spanish hospitals and who had reached the SVR 12 evaluation time-point were selected. TW4 HCV-RNA levels were categorized as target-not-detected (TND), below the lower limit of quantification (LLOQ TD ) and ≥LLOQ. A total of 123 patients were included, 86 (70%) received sofosbuvir/ daclatasvir±ribavirin, 27 (22%) received sofosbuvir/ ledipasvir/ ribavirin and 10 (8.1%) received sofosbuvir/ ribavirin, respectively. In all, 114 (92.7%) of the 123 patients presented SVR 12 in an on-treatment approach, but nine (7.3%) patients relapsed, all of them had presented cirrhosis at baseline. In those who achieved TND, LLOQ TD and ≥LLOQ, SVR 12 was observed in 81/83 (98%; 95% CI 91.5%-99.7%), 24/28 (85.7%; 95% CI 67.3%-96%) and 9/12 (75%; 95% CI 42.8%-94.5%), respectively; p (linear association) 0.001. Corresponding numbers for subjects with cirrhosis were: 52/54 (96.3%; 95% CI 87.3%-95.5%), 14/18 (77.8%; 95% CI 52.4%-93.6%) and 7/10 (70%; 95% CI 34.8%-93.3%); p 0.004. TW4-response indicates the probability of achieving SVR 12 to currently used DAA-based therapy in HCV genotype 3-infected individuals with cirrhosis. This finding may be useful to tailor treatment strategy in this setting. Copyright © 2017 European Society of Clinical Microbiology and Infectious Diseases. Published by Elsevier Ltd. All rights reserved.

Identification of targets for rational pharmacological therapy in childhood craniopharyngioma.

PubMed

Gump, Jacob M; Donson, Andrew M; Birks, Diane K; Amani, Vladimir M; Rao, Karun K; Griesinger, Andrea M; Kleinschmidt-DeMasters, B K; Johnston, James M; Anderson, Richard C E; Rosenfeld, Amy; Handler, Michael; Gore, Lia; Foreman, Nicholas; Hankinson, Todd C

2015-05-21

Pediatric adamantinomatous craniopharyngioma (ACP) is a histologically benign but clinically aggressive brain tumor that arises from the sellar/suprasellar region. Despite a high survival rate with current surgical and radiation therapy (75-95 % at 10 years), ACP is associated with debilitating visual, endocrine, neurocognitive and psychological morbidity, resulting in excheptionally poor quality of life for survivors. Identification of an effective pharmacological therapy could drastically decrease morbidity and improve long term outcomes for children with ACP. Using mRNA microarray gene expression analysis of 15 ACP patient samples, we have found several pharmaceutical targets that are significantly and consistently overexpressed in our panel of ACP relative to other pediatric brain tumors, pituitary tumors, normal pituitary and normal brain tissue. Among the most highly expressed are several targets of the kinase inhibitor dasatinib - LCK, EPHA2 and SRC; EGFR pathway targets - AREG, EGFR and ERBB3; and other potentially actionable cancer targets - SHH, MMP9 and MMP12. We confirm by western blot that a subset of these targets is highly expressed in ACP primary tumor samples. We report here the first published transcriptome for ACP and the identification of targets for rational therapy. Experimental drugs targeting each of these gene products are currently being tested clinically and pre-clinically for the treatment of other tumor types. This study provides a rationale for further pre-clinical and clinical studies of novel pharmacological treatments for ACP. Development of mouse and cell culture models for ACP will further enable the translation of these targets from the lab to the clinic, potentially ushering in a new era in the treatment of ACP.

Evolving targeted therapies for right ventricular failure.

PubMed

Di Salvo, Thomas G

2015-01-01

Although right and left ventricular embryological origins, morphology and cardiodynamics differ, the notion of selectively targeted right ventricular therapies remains controversial. This review focuses on both the currently evolving pharmacologic agents targeting right ventricular failure (metabolic modulators, phosphodiesterase type V inhibitors) and future therapeutic approaches including epigenetic modulation by miRNAs, chromatin binding complexes, long non-coding RNAs, genomic editing, adoptive gene transfer and gene therapy, cell regeneration via cell transplantation and cell reprogramming and cardiac tissue engineering. Strategies for adult right ventricular regeneration will require a more holistic approach than strategies for adult left ventricular failure. Instances of right ventricular failure requiring global reconstitution of right ventricular myocardium, attractive approaches include: i) myocardial patches seeded with cardiac fibroblasts reprogrammed into cardiomyocytes in vivo by small molecules, miRNAs or other epigenetic modifiers; and ii) administration of miRNAs, lncRNAs or small molecules by non-viral vector delivery systems targeted to fibroblasts (e.g., episomes) to stimulate in vivo reprogramming of fibroblasts into cardiomyocytes. For selected heritable genetic myocardial diseases, genomic editing affords exciting opportunities for allele-specific silencing by site-specific directed silencing, mutagenesis or gene excision. Genomic editing by adoptive gene transfer affords similarly exciting opportunities for restoration of myocardial gene expression.

RNA-Targeted Therapies and Amyotrophic Lateral Sclerosis

PubMed Central

Le Masson, Gwendal

2018-01-01

Amyotrophic lateral sclerosis (ALS) is a fatal motor disease in adults. Its pathophysiology remains mysterious, but tremendous advances have been made with the discovery of the most frequent mutations of its more common familial form linked to the C9ORF72 gene. Although most cases are still considered sporadic, these genetic mutations have revealed the role of RNA production, processing and transport in ALS, and may be important players in all ALS forms. There are no disease-modifying treatments for adult human neurodegenerative diseases, including ALS. As in spinal muscular atrophy, RNA-targeted therapies have been proposed as potential strategies for treating this neurodegenerative disorder. Successes achieved in various animal models of ALS have proven that RNA therapies are both safe and effective. With careful consideration of the applicability of such therapies in humans, it is possible to anticipate ongoing in vivo research and clinical trial development of RNA therapies for treating ALS. PMID:29342921

RNA-Targeted Therapies and Amyotrophic Lateral Sclerosis.

PubMed

Mathis, Stéphane; Le Masson, Gwendal

2018-01-15

Amyotrophic lateral sclerosis (ALS) is a fatal motor disease in adults. Its pathophysiology remains mysterious, but tremendous advances have been made with the discovery of the most frequent mutations of its more common familial form linked to the C9ORF72 gene. Although most cases are still considered sporadic, these genetic mutations have revealed the role of RNA production, processing and transport in ALS, and may be important players in all ALS forms. There are no disease-modifying treatments for adult human neurodegenerative diseases, including ALS. As in spinal muscular atrophy, RNA-targeted therapies have been proposed as potential strategies for treating this neurodegenerative disorder. Successes achieved in various animal models of ALS have proven that RNA therapies are both safe and effective. With careful consideration of the applicability of such therapies in humans, it is possible to anticipate ongoing in vivo research and clinical trial development of RNA therapies for treating ALS.

Combinations of Adefovir with Nucleoside Analogs Produce Additive Antiviral Effects against Hepatitis B Virus In Vitro

PubMed Central

Delaney, William E.; Yang, Huiling; Miller, Michael D.; Gibbs, Craig S.; Xiong, Shelly

2004-01-01

Combination therapies may be required for long-term management of some patients chronically infected with hepatitis B virus (HBV). Adefovir is a nucleotide analog that has similar activity against wild-type and lamivudine-resistant HBV. In contrast to lamivudine, clinical resistance to the prodrug adefovir dipivoxil emerges infrequently. Based on its clinical efficacy and low frequency of resistance, adefovir dipivoxil may form an important component of combination regimens. We therefore investigated the in vitro antiviral efficacy of combinations of adefovir with other nucleoside analogs (lamivudine, entecavir, emtricitabine [FTC],and telbivudine [L-dT]) and the nucleotide analog tenofovir. Using a novel stable cell line that expresses high levels of wild-type HBV, we assayed the antiviral activity of each drug alone and in combination with adefovir. All two-drug combinations resulted in greater antiviral effects than treatments with single agents and could be characterized as additive by the Bliss independence model. Analysis using the Loewe additivity model indicated that adefovir exerted additive antiviral effects when combined with lamivudine, FTC, or L-dT and moderately synergistic effects when combined with entecavir or tenofovir. There was no evidence of cytotoxicity with any of the drugs when used alone or in combination at the tested doses. PMID:15388423

Molecular Approach to Targeted Therapy for Multiple Sclerosis.

PubMed

Sherbet, Gajanan V

2016-01-01

The development and evolution of targeted therapy to any disease require the identification of targets amenable to treatment of patients. Here the pathogenetic signalling systems involved in multiple sclerosis are scrutinised to locate nodes of deregulation and dysfunction in order to devise strategies of drug development for targeted intervention. Oliogoclonal bands (OCB) are isoelectric focusing profiles of immunoglobulins synthesised in the central nervous system. OCBs enable the diagnosis of multiple sclerosis with high sensitivity and specificity and are related to the course of the disease and progression. The OCB patterns can be linked with the expression of angiogenic molecular species. Angiogenic signalling which has also been implicated in demyelination provides the option of using angiogenesis inhibitors in disease control. The PI3K (phosphoinositide 3-kinase)/Akt axis has emerged with a key role in myelination with its demonstrable links with mTOR mediated transcription of downstream target genes. Inflammatory signals and innate and acquired immunity from the activation of NF-κB (nuclear factor κB) responsive genes are considered. NF-κB signalling could be implicated in myelination. The transcription factor STAT (signal transducers and activators of transcription) and the EBV (Epstein- Barr virus) transcription factor BZLF1 contributing significantly to the disease process are a major environmental factor linked to MS. EBV can activate TGF (transforming growth factor) and VEGF (vascular endothelial growth factor) signalling. EBV microRNAs are reviewed as signalling mediators of pathogenesis. Stem cell transplantation therapy has lately gained much credence, so the current status of mesenchymal and hematopoietic stem cell therapy is reviewed with emphasis on the differential expression immune-related genes and operation of signalling systems.

Mechanisms of Hepatitis C Viral Resistance to Direct Acting Antivirals.

PubMed

Ahmed, Asma; Felmlee, Daniel J

2015-12-18

There has been a remarkable transformation in the treatment of chronic hepatitis C in recent years with the development of direct acting antiviral agents targeting virus encoded proteins important for viral replication including NS3/4A, NS5A and NS5B. These agents have shown high sustained viral response (SVR) rates of more than 90% in phase 2 and phase 3 clinical trials; however, this is slightly lower in real-life cohorts. Hepatitis C virus resistant variants are seen in most patients who do not achieve SVR due to selection and outgrowth of resistant hepatitis C virus variants within a given host. These resistance associated mutations depend on the class of direct-acting antiviral drugs used and also vary between hepatitis C virus genotypes and subtypes. The understanding of these mutations has a clear clinical implication in terms of choice and combination of drugs used. In this review, we describe mechanism of action of currently available drugs and summarize clinically relevant resistance data.

New perspectives on targeted therapy in ovarian cancer

PubMed Central

Coward, Jermaine IG; Middleton, Kathryn; Murphy, Felicity

2015-01-01

Epithelial ovarian cancer remains the most lethal gynecologic malignancy. During the last 15 years, there has been only marginal improvement in 5 year overall survival. These daunting statistics are compounded by the fact that despite all subtypes exhibiting striking heterogeneity, their systemic management remains identical. Although changes to the scheduling and administration of chemotherapy have improved outcomes to a degree, a therapeutic ceiling is being reached with this approach, resulting in a number of trials investigating the efficacy of targeted therapies alongside standard treatment algorithms. Furthermore, there is an urge to develop subtype-specific studies in an attempt to improve outcomes, which currently remain poor. This review summarizes the key studies with antiangiogenic agents, poly(adenosine diphosphate [ADP]-ribose) inhibitors, and epidermal growth factor receptor/human epidermal growth factor receptor family targeting, in addition to folate receptor antagonists and insulin growth factor receptor inhibitors. The efficacy of treatment paradigms used in non-ovarian malignancies for type I tumors is also highlighted, in addition to recent advances in appropriate patient stratification for targeted therapies in epithelial ovarian cancer. PMID:25678824

Recent advances in therapeutic recruitment of mammalian RNAi and bacterial CRISPR-Cas DNA interference pathways as emerging antiviral strategies.

PubMed

Chin, Wei-Xin; Ang, Swee Kim; Chu, Justin Jang Hann

2017-01-01

In invertebrate eukaryotes and prokaryotes, respectively, the RNAi and clustered regularly interspaced short palindromic repeats-CRISPR-associated (CRISPR-Cas) pathways are highly specific and efficient RNA and DNA interference systems, and are well characterised as potent antiviral systems. It has become possible to recruit or reconstitute these pathways in mammalian cells, where they can be directed against desired host or viral targets. The RNAi and CRISPR-Cas systems can therefore yield ideal antiviral therapeutics, capable of specific and efficient viral inhibition with minimal off-target effects, but development of such therapeutics can be slow. This review covers recent advances made towards developing RNAi or CRISPR-Cas strategies for clinical use. These studies address the delivery, toxicity or target design issues that typically plague the in vivo or clinical use of these technologies. Copyright © 2016 Elsevier Ltd. All rights reserved.

Hydrogen bonds and antiviral activity of benzaldehyde derivatives

NASA Astrophysics Data System (ADS)

Tolstorozhev, G. B.; Skornyakov, I. V.; Belkov, M. V.; Shadyro, O. I.; Brinkevich, S. D.; Samovich, S. N.

2012-09-01

We have obtained the Fourier transform IR spectra of solutions of benzaldehyde derivatives having different antiviral activities against a herpes virus. We observe a correlation between the presence of hydrogen bonds in the benzaldehyde molecules and the appearance of antiviral properties in the compounds. For compounds having antiviral activity, we have obtained spectral data suggesting the existence of hydrogen bonds of the type C=OṡṡṡH-O and O-HṡṡṡO in the molecules. When the hydrogen atom in the hydroxyl groups are replaced by a methyl group, no intramolecular hydrogen bonds are formed and the compounds lose their antiviral activity.

Oral antivirals for the acute treatment of recurrent herpes labialis.

PubMed

Jensen, Lori A; Hoehns, James D; Squires, Cindy L

2004-04-01

To evaluate the use and benefit of oral antivirals in the acute treatment of episodic, recurrent herpes labialis. A literature search was performed in MEDLINE (1966-August 2003) using acyclovir, famciclovir, valacyclovir, cold sores, herpes labialis, and HSV-1 as search terms. We reviewed 5 placebo-controlled and 2 comparative studies evaluating oral antivirals for acute treatment of recurrent herpes labialis. No studies directly compared different antivirals. Studies discussing the efficacy of antivirals for chronic suppression of herpes simplex virus-1 infection were not included. Treatment with oral antivirals decreases the duration of lesion episodes and pain by approximately one day; however, the antivirals do not abort lesions from developing. Clinical implications of these results appear relatively modest.

Drug resistance to targeted therapies: déjà vu all over again.

PubMed

Groenendijk, Floris H; Bernards, René

2014-09-12

A major limitation of targeted anticancer therapies is intrinsic or acquired resistance. This review emphasizes similarities in the mechanisms of resistance to endocrine therapies in breast cancer and those seen with the new generation of targeted cancer therapeutics. Resistance to single-agent cancer therapeutics is frequently the result of reactivation of the signaling pathway, indicating that a major limitation of targeted agents lies in their inability to fully block the cancer-relevant signaling pathway. The development of mechanism-based combinations of targeted therapies together with non-invasive molecular disease monitoring is a logical way forward to delay and ultimately overcome drug resistance development. Copyright © 2014 Federation of European Biochemical Societies. Published by Elsevier B.V. All rights reserved.

Antiviral Defense Mechanisms in Honey Bees

PubMed Central

Brutscher, Laura M.; Daughenbaugh, Katie F.; Flenniken, Michelle L.

2015-01-01

Honey bees are significant pollinators of agricultural crops and other important plant species. High annual losses of honey bee colonies in North America and in some parts of Europe have profound ecological and economic implications. Colony losses have been attributed to multiple factors including RNA viruses, thus understanding bee antiviral defense mechanisms may result in the development of strategies that mitigate colony losses. Honey bee antiviral defense mechanisms include RNA-interference, pathogen-associated molecular pattern (PAMP) triggered signal transduction cascades, and reactive oxygen species generation. However, the relative importance of these and other pathways is largely uncharacterized. Herein we review the current understanding of honey bee antiviral defense mechanisms and suggest important avenues for future investigation. PMID:26273564

Factor XI as a target for antithrombotic therapy

PubMed Central

Bane, Charles E.; Gailani, David

2014-01-01

Anticoagulants currently used in clinical practice to treat thromboembolic disorders are effective but increase the risk of severe bleeding because they target proteins that are essential for normal coagulation (hemostasis). Drugs with better safety profiles are required for prevention and treatment of thromboembolic disease. Coagulation factor XIa has emerged as a novel target for safer anticoagulant therapy because of its role in thrombosis and its relatively small contribution to hemostasis. PMID:24886766

Prostate Specific Membrane Antigen (PSMA) Targeted Bio-orthogonal Therapy for Metastatic Prostate Cancer

DTIC Science & Technology

2017-10-01

AWARD NUMBER: W81XWH-16-1-0595 TITLE: Prostate-Specific Membrane Antigen (PSMA) Targeted Bio -orthogonal Therapy for Metastatic Prostate Cancer...Sep 2016 - 14 Sep 2017 4. TITLE AND SUBTITLE Prostate-Specific Membrane Antigen (PSMA) Targeted Bio -orthogonal Therapy for Metastatic Prostate

Targeted alpha therapy using short-lived alpha-particles and the promise of nanobodies as targeting vehicle

PubMed Central

Dekempeneer, Yana; Keyaerts, Marleen; Krasniqi, Ahmet; Puttemans, Janik; Muyldermans, Serge; Lahoutte, Tony; D’huyvetter, Matthias; Devoogdt, Nick

2016-01-01

ABSTRACT Introduction: The combination of a targeted biomolecule that specifically defines the target and a radionuclide that delivers a cytotoxic payload offers a specific way to destroy cancer cells. Targeted radionuclide therapy (TRNT) aims to deliver cytotoxic radiation to cancer cells and causes minimal toxicity to surrounding healthy tissues. Recent advances using α-particle radiation emphasizes their potential to generate radiation in a highly localized and toxic manner because of their high level of ionization and short range in tissue. Areas covered: We review the importance of targeted alpha therapy (TAT) and focus on nanobodies as potential beneficial vehicles. In recent years, nanobodies have been evaluated intensively as unique antigen-specific vehicles for molecular imaging and TRNT. Expert opinion: We expect that the efficient targeting capacity and fast clearance of nanobodies offer a high potential for TAT. More particularly, we argue that the nanobodies’ pharmacokinetic properties match perfectly with the interesting decay properties of the short-lived α-particle emitting radionuclides Astatine-211 and Bismuth-213 and offer an interesting treatment option particularly for micrometastatic cancer and residual disease. PMID:27145158

Activation of innate antiviral immune response via double-stranded RNA-dependent RLR receptor-mediated necroptosis

PubMed Central

Wang, Wei; Wang, Wei-Hua; Azadzoi, Kazem M.; Su, Ning; Dai, Peng; Sun, Jianbin; Wang, Qin; Liang, Ping; Zhang, Wentao; Lei, Xiaoying; Yan, Zhen; Yang, Jing-Hua

2016-01-01

Viruses induce double-stranded RNA (dsRNA) in the host cells. The mammalian system has developed dsRNA-dependent recognition receptors such as RLRs that recognize the long stretches of dsRNA as PAMPs to activate interferon-mediated antiviral pathways and apoptosis in severe infection. Here we report an efficient antiviral immune response through dsRNA-dependent RLR receptor-mediated necroptosis against infections from different classes of viruses. We demonstrated that virus-infected A549 cells were efficiently killed in the presence of a chimeric RLR receptor, dsCARE. It measurably suppressed the interferon antiviral pathway but promoted IL-1β production. Canonical cell death analysis by morphologic assessment, phosphatidylserine exposure, caspase cleavage and chemical inhibition excluded the involvement of apoptosis and consistently suggested RLR receptor-mediated necroptosis as the underlying mechanism of infected cell death. The necroptotic pathway was augmented by the formation of RIP1-RIP3 necrosome, recruitment of MLKL protein and the activation of cathepsin D. Contributing roles of RIP1 and RIP3 were confirmed by gene knockdown. Furthermore, the necroptosis inhibitor necrostatin-1 but not the pan-caspase inhibitor zVAD impeded dsCARE-dependent infected cell death. Our data provides compelling evidence that the chimeric RLR receptor shifts the common interferon antiviral responses of infected cells to necroptosis and leads to rapid death of the virus-infected cells. This mechanism could be targeted as an efficient antiviral strategy. PMID:26935990

Epithelioid Sarcoma: Opportunities for Biology-Driven Targeted Therapy.

PubMed

Noujaim, Jonathan; Thway, Khin; Bajwa, Zia; Bajwa, Ayeza; Maki, Robert G; Jones, Robin L; Keller, Charles

2015-01-01

Epithelioid sarcoma (ES) is a soft tissue sarcoma of children and young adults for which the preferred treatment for localized disease is wide surgical resection. Medical management is to a great extent undefined, and therefore for patients with regional and distal metastases, the development of targeted therapies is greatly desired. In this review, we will summarize clinically relevant biomarkers (e.g., SMARCB1, CA125, dysadherin, and others) with respect to targeted therapeutic opportunities. We will also examine the role of EGFR, mTOR, and polykinase inhibitors (e.g., sunitinib) in the management of local and disseminated disease. Toward building a consortium of pharmaceutical, academic, and non-profit collaborators, we will discuss the state of resources for investigating ES with respect to cell line resources, tissue banks, and registries so that a roadmap can be developed toward effective biology-driven therapies.

The benefits of steroids versus steroids plus antivirals for treatment of Bell’s palsy: a meta-analysis

PubMed Central

Quant, Eudocia C; Jeste, Shafali S; Muni, Rajeev H; Cape, Alison V; Bhussar, Manveen K

2009-01-01

recovery compared with steroids alone in patients with Bell’s palsy. This study does not, therefore, support the routine use of antivirals in Bell’s palsy. Future studies should use improved herpes virus diagnostics and newer antivirals to assess whether combination therapy benefits patients with more severe facial paralysis at study entry. PMID:19736282

Targeted therapies in hepatocellular carcinoma.

PubMed

Bronte, F; Bronte, G; Cusenza, S; Fiorentino, E; Rolfo, C; Cicero, G; Bronte, E; Di Marco, V; Firenze, A; Angarano, G; Fontana, T; Russo, A

2014-01-01

The onset of hepatocellular carcinoma (HCC) is related to the development of non-neoplastic liver disease, such as viral infections and cirrhosis. Even though patients with chronic liver diseases undergo clinical surveillance for early diagnosis of HCC, this cancer is often diagnosed in advanced stage. In this case locoregional treatment is not possible and systemic therapies are the best way to control it. Until now sorafenib, a Raf and multi-kinase inhibitor has been the best, choice to treat HCC systemically. It showed a survival benefit in multicenter phase III trials. However the proper patient setting to treat is not well defined, since the results in Child-Pugh B patients are conflicting. To date various new target drugs are under developed and other biological treatments normally indicated in other malignancies are under investigation also for HCC. These strategies aim to target the different biological pathways implicated in HCC development and progression. The target drugs studied in HCC include anti-VEGF and anti-EGFR monoclonal antibodies, tyrosine kinase inhibitors and mTOR inhibitors. The most important challenge is represented by the best integration of these drugs with standard treatments to achieve improvement in overall survival and quality of life.

Why Targeted Therapies are Necessary for Systemic Lupus Erythematosus

PubMed Central

Durcan, Laura; Petri, Michelle

2016-01-01

Systemic lupus erythematosus (SLE) continues to have important morbidity and accelerated mortality despite therapeutic advances. Targeted therapies offer the possibility of improved efficacy with fewer side-effects. Current management strategies rely heavily on non-specific immunosuppressive agents. Prednisone, in particular, is responsible for a considerable burden of later organ damage. There are a multitude of diverse mechanisms of disease activity, immunogenic abnormalities and clinical manifestations to take into consideration in SLE. Many targeted agents with robust mechanistic pre-clinical data and promising early phase studies have ultimately been disappointing in phase III randomized controlled studies. Recent efforts have focused on B cell therapies, in particular given the success of belimumab in clinical trials, with limited success. We remain optimistic regarding other specific therapies being evaluated including interferon alpha blockade. It is likely that in SLE, given the heterogeneity of the population involved, precision medicine is needed, rather than expecting that any single biologic will be universally effective. PMID:27497251

The life cycle of non-polio enteroviruses and how to target it.

PubMed

Baggen, Jim; Thibaut, Hendrik Jan; Strating, Jeroen R P M; van Kuppeveld, Frank J M

2018-06-01

The genus Enterovirus (EV) of the family Picornaviridae includes poliovirus, coxsackieviruses, echoviruses, numbered enteroviruses and rhinoviruses. These diverse viruses cause a variety of diseases, including non-specific febrile illness, hand-foot-and-mouth disease, neonatal sepsis-like disease, encephalitis, paralysis and respiratory diseases. In recent years, several non-polio enteroviruses (NPEVs) have emerged as serious public health concerns. These include EV-A71, which has caused epidemics of hand-foot-and-mouth disease in Southeast Asia, and EV-D68, which recently caused a large outbreak of severe lower respiratory tract disease in North America. Infections with these viruses are associated with severe neurological complications. For decades, most research has focused on poliovirus, but in recent years, our knowledge of NPEVs has increased considerably. In this Review, we summarize recent insights from enterovirus research with a special emphasis on NPEVs. We discuss virion structures, host-receptor interactions, viral uncoating and the recent discovery of a universal enterovirus host factor that is involved in viral genome release. Moreover, we briefly explain the mechanisms of viral genome replication, virion assembly and virion release, and describe potential targets for antiviral therapy. We reflect on how these recent discoveries may help the development of antiviral therapies and vaccines.

Update on B-cell targeted therapies for systemic lupus erythematosus.

PubMed

Mok, Chi Chiu

2014-06-01

Systemic lupus erythematosus (SLE) is a systemic autoimmune disease characterized by flares and remission, leading to accrual of organ damage over time as a result of persistent tissue inflammation and treatment-related complications. Novel therapies aiming at better treatment response and fewer adverse effects are being tested in the pipeline. This review summarizes the B-cell abnormalities observed in patients with SLE, and updates recent data on the efficacy and safety of B-cell targeted therapies in the treatment of SLE. The pitfalls of clinical trial design and future directions of the development of SLE therapeutics are discussed. The variability of clinical response to treatment in SLE reflects the clinical and immunological heterogeneity of the disease. The treatment plan for patients with SLE should be individualized with the aim of eradicating disease activity, preventing flares and minimizing treatment-related complications. Despite the disappointment of recent clinical trials, B-cell remains the promising target of future SLE therapies. Results from ongoing clinical trials on B-cell targeted biological agents are eagerly awaited.

Oncogenic drivers, targeted therapies, and acquired resistance in non-small-cell lung cancer.

PubMed

Gower, Arjan; Wang, Yisong; Giaccone, Giuseppe

2014-07-01

In the past decade, a shift toward targeted therapies in non-small-cell lung cancer following molecular profiling has dramatically changed the way advanced adenocarcinoma is treated. However, tumor cells inevitably acquire resistance to such therapies, circumventing any sustained clinical benefit. As the genomic classification of lung cancer continues to evolve and as the mechanisms of acquired resistance to targeted therapies become elucidated and more improved target-specific drugs come into sight, the future will see more promising results from the clinic through the development of new therapeutic strategies to overcome, or prevent the development of, resistance for lung cancer patients.

Antiviral effect of emodin from Rheum palmatum against coxsakievirus B5 and human respiratory syncytial virus in vitro.

PubMed

Liu, Zhao; Ma, Nian; Zhong, Yan; Yang, Zhan-qiu

2015-12-01

Viral infections are the major causes of morbidity and mortality in elderly people and young children throughout the world. The most common pathogens include coxsackie virus (CV) and respiratory syncytial virus (RSV). However, no antiviral agents with low toxicity and drug resistance are currently available in clinic therapy. The present study aimed to examine the antiviral activities of emodin (an ingredient of Rheum palmatum) against CVB5 and RSV infections, in an attempt to discover new antiviral agents for virus infection. The monomer emodin was extracted and isolated from Rheum palmatum. The antiviral activities of emodin on HEp-2 cells were evaluated, including virus replication inhibition, virucidal and anti-absorption effects, by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tet-razolium bromide (MTT) assay and plaque reduction assay (PRA). The kinetics of virus inhibition by emodin in a period of 14 h was further determined by plaque assay and quantitative real time PCR (qPCR). Cytokine (IFN-γ, TNF-α) mRNA expressions after emodin treatment (7.5, 15, 30 μmol/L) were also assessed by qPCR post-infection. The results showed that emodin had potent inhibitory activities against CVB5 and RSV, with the 50% effective concentration (EC50) ranging from 13.06 to 14.27 μmol/L and selectivity index (SI) being 5.38-6.41 μmol/L. However, emodin couldn't directly inactivate the viruses or block their absorption to cells. It acted as a biological synthesis inhibitor against CVB4 and RSV in a concentration- and time-dependent manner, especially during the first 0-4 h post-infection. Moreover, emodin could decrease the mRNA expression of IFN-α but enhance TNF-γ expression significantly compared to the viral controls in vitro. Our results provide a molecular basis for development of emodin as a novel and safe antiviral agent for human enterovirus and respiratory virus infection in the clinical therapy.

ESCMID Study Group for Infections in Compromised Hosts (ESGICH) Consensus Document on the safety of targeted and biological therapies: an infectious diseases perspective (Cell surface receptors and associated signaling pathways).

PubMed

Aguilar-Company, J; Fernández-Ruiz, M; García-Campelo, R; Garrido-Castro, A C; Ruiz-Camps, I

2018-06-01

The present review is part of the European Society of Clinical Microbiology and Infectious Diseases (ESCMID) Study Group for Infections in Compromised Hosts (ESGICH) consensus document on the safety of targeted and biologic therapies. To review, from an infectious diseases perspective, the safety profile of therapies targeting cell surface receptors and associated signaling pathways among cancer patients and to suggest preventive recommendations. Computer-based Medline searches with MeSH terms pertaining to each agent or therapeutic family. Vascular endothelial growth factor (VEGF)-targeted agents (bevacizumab and aflibercept) are associated with a meaningful increase in the risk of infection, likely due to drug-induced neutropaenia, although no clear benefit is expected from the universal use of anti-infective prophylaxis. VEGF tyrosine kinase inhibitors (i.e. sorafenib or sunitinib) do not seem to significantly affect host's susceptibility to infection, and universal anti-infective prophylaxis is not recommended either. Anti-epidermal growth factor receptor (EGFR) monoclonal antibodies (cetuximab or panitumumab) induce neutropaenia and secondary skin and soft tissue infection in cases of severe papulopustular rash. Systemic antibiotics (doxycycline or minocycline) should be administered to prevent the latter complication, whereas no recommendation can be established on the benefit from antiviral, antifungal or anti-Pneumocystis prophylaxis. A lower risk of infection is reported for anti-ErbB2/HER2 monoclonal antibodies (trastuzumab and pertuzumab) and ErbB receptor tyrosine kinase inhibitors (including dual-EGFR/ErbB2 inhibitors such as lapatinib or neratinib) compared to conventional chemotherapy, presumably as a result of the decreased occurrence of drug-induced neutropaenia. With the exception of VEGF-targeted agents, the overall risk of infection associated with the reviewed therapies seems to be low. Copyright © 2018 European Society of Clinical

Comparison of the clinical outcomes between antiviral-naïve patients treated with entecavir and lamivudine-resistant patients receiving adefovir add-on lamivudine combination treatment

PubMed Central

Kim, Hong Joo; Park, Soo Kyung; Yang, Hyo Joon; Jung, Yoon Suk; Park, Jung Ho; Park, Dong Il; Cho, Yong Kyun; Sohn, Chong Il; Jeon, Woo Kyu; Kim, Byung Ik; Choi, Kyu Yong

2016-01-01

Background/Aims To analyze the effects of preexisting lamivudine (LAM) resistance and applying antiviral treatment (adefovir [ADV] add-on LAM combination treatment) on long-term treatment outcomes, and comparing the clinical outcomes of antiviral-naïve chronic hepatitis B patients receiving entecavir (ETV) monotherapy. Methods This study enrolled 73 antiviral-naïve patients who received 0.5-mg ETV as an initial therapy and 54 patients who received ADV add-on LAM combination treatment as a rescue therapy from July 2006 to July 2010. Results During 24-month treatments, the decreases in serum log10HBV-DNA values (copies/mL) were significantly greater in the antiviral-naïve patients treated with ETV than the patients receiving ADV add-on LAM combination treatment. The biochemical response rates for alanine aminotransferase normalization at 6 months (ETV) and 12 months (ADV add-on LAM) were 90.4% (66/73) and 77.8% (42/54), respectively (P=0.048). A Kaplan-Meier analysis indicated that the rates of serologic response, viral breakthrough, and emergence of genotypic resistance did not differ significantly between the two patient groups. There were also no significant intergroup differences in the rates of disease progression (PD) and new development of hepatocellular carcinoma (HCC). Conclusion The long-term clinical outcomes of antiviral-naïve patients treated with ETV and LAM-resistant patients receiving ADV add-on LAM combination treatment were comparable in terms of the emergence of HCC and disease progression. PMID:27729626

[Molecular-targeted therapy for neurodegenerative diseases].

PubMed

Sobue, Gen

2009-11-01

Neurodegenerative diseases have been construed as incurable disorders. However, therapeutic development for these diseases is now facing a turning point: analyses of cellular and animal models have provided insights into pathogenesis of neurodegenerative diseases, and have indicated rational therapeutic approaches to them. Therefore, how to realize molecular targeted therapy for neurodegenerative diseases is becoming one of the most challenging issues in the clinical neurology. Primarily, pathophysiological understanding of the disease from basic science is the first step. For the successful clinical trials, effective trial design, sufficient economic and social support, and education are indispensable. The development of androgen deprivation therapy for spinal and bulbar muscular atrophy (SBMA) is a representative study in this field. SBMA is a hereditary neurodegenerative disease caused by expansion of a trinucleotide CAG repeat in the first exon of the androgen receptor (AR) gene. There is increasing evidence that testosterone, the ligand of AR, plays a pivotal role in the neurodegeneration in SBMA. The striking success of androgen deprivation therapy in SBMA mouse models has been translated into phase 2, and then phase 3, clinical trials.

Antiviral Perspectives for Chikungunya Virus

PubMed Central

Cherian, Sarah

2014-01-01

Chikungunya virus (CHIKV) is a mosquito-borne pathogen that has a major health impact in humans and causes acute febrile illness in humans accompanied by joint pains and, in many cases, persistent arthralgia lasting for weeks to years. CHIKV reemerged in 2005-2006 in several parts of the Indian Ocean islands and India after a gap of 32 years, causing millions of cases. The re-emergence of CHIKV has also resulted in numerous outbreaks in several countries in the eastern hemisphere, with a threat to further expand in the near future. However, there is no vaccine against CHIKV infection licensed for human use, and therapy for CHIKV infection is still mainly limited to supportive care as antiviral agents are yet in different stages of testing or development. In this review we explore the different perspectives for chikungunya treatment and the effectiveness of these treatment regimens and discuss the scope for future directions. PMID:24955364

Cancer gene therapy with targeted adenoviruses.

PubMed

Bachtarzi, Houria; Stevenson, Mark; Fisher, Kerry

2008-11-01

Clinical experience with adenovirus vectors has highlighted the need for improved delivery and targeting. This manuscript aims to provide an overview of the techniques currently under development for improving adenovirus delivery to malignant cells in vivo. Primary research articles reporting improvements in adenoviral gene delivery are described. Strategies include genetic modification of viral coat proteins, non-genetic modifications including polymer encapsulation approaches and pharmacological interventions. Reprogramming adenovirus tropism in vitro has been convincingly demonstrated using a range of genetic and physical strategies. These studies have provided new insights into our understanding of virology and the field is progressing. However, there are still some limitations that need special consideration before adenovirus-targeted cancer gene therapy emerges as a routine treatment in the clinical setting.

Intranasal administration of poly-gamma glutamate induced antiviral activity and protective immune responses against H1N1 influenza A virus infection.

PubMed

Kim, Eun-Ha; Choi, Young-Ki; Kim, Chul-Joong; Sung, Moon-Hee; Poo, Haryoung

2015-10-06

The global outbreak of a novel swine-origin strain of the 2009 H1N1 influenza A virus and the sudden, worldwide increase in oseltamivir-resistant H1N1 influenza A viruses highlight the urgent need for novel antiviral therapy. Here, we investigated the antiviral efficacy of poly-gamma glutamate (γ-PGA), a safe and edible biomaterial that is naturally synthesized by Bacillus subtilis, against A/Puerto Rico/8/1934 (PR8) and A/California/04/2009 (CA04) H1N1 influenza A virus infections in C57BL/6 mice. Intranasal administration of γ-PGA for 5 days post-infection improved survival, increased production of antiviral cytokines including interferon-beta (IFN-β) and interleukin-12 (IL-12), and enhanced activation of natural killer (NK) cells and influenza antigen-specific cytotoxic T lymphocytes (CTL) activity. These results suggest that γ-PGA protects mice against H1N1 influenza A virus by enhancing antiviral immune responses.

An overview of targeted alpha therapy with 225Actinium and 213Bismuth.

PubMed

Morgenstern, Alfred; Apostolidis, Christos; Kratochwil, Clemens; Sathekge, Mike; Krolicki, Leszek; Bruchertseifer, Frank

2018-05-01

Recent reports of the remarkable therapeutic efficacy of 225Ac-labeled PSMA-617 for therapy of metastatic castration-resistant prostate cancer have underlined the clinical potential of targeted alpha therapy. This review describes methods for the production of 225Ac and its daughter nuclide 213Bi and summarizes the current clinical experience with both alpha emitters with particular focus on recent studies of targeted alpha therapy of bladder cancer, brain tumors, neuroendocrine tumors and prostate cancer. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Infectious pancreatic necrosis virus triggers antiviral immune response in rainbow trout red blood cells, despite not being infective

PubMed Central

Nombela, Ivan; Carrion, Aurora; Puente-Marin, Sara; Chico, Verónica; Mercado, Luis; Perez, Luis; Coll, Julio; Ortega-Villaizan, Maria del Mar

2017-01-01

Background: Some fish viruses, such as piscine orthoreovirus and infectious salmon anemia virus, target red blood cells (RBCs), replicate inside them and induce an immune response. However, the roles of RBCs in the context of infectious pancreatic necrosis virus (IPNV) infection  have not been studied yet. Methods: Ex vivo rainbow trout RBCs were obtained from peripheral blood, Ficoll purified and exposed to IPNV in order to analyze infectivity and immune response using RT-qPCR, immune fluorescence imaging, flow cytometry and western-blotting techniques. Results: IPNV could not infect RBCs; however, IPNV increased the expression of the INF1-related genes ifn-1, pkr and mx genes. Moreover, conditioned media from IPNV-exposed RBCs conferred protection against IPNV infection in CHSE-214 fish cell line. Conclusions: Despite not being infected, rainbow trout RBCs could respond to IPNV with increased expression of antiviral genes. Fish RBCs could be considered as mediators of the antiviral response and therefore targets of new strategies against fish viral infections. Further research is ongoing to completely understand the molecular mechanism that triggers this antiviral response in rainbow trout RBCs. PMID:29333244

Infectious pancreatic necrosis virus triggers antiviral immune response in rainbow trout red blood cells, despite not being infective.

PubMed

Nombela, Ivan; Carrion, Aurora; Puente-Marin, Sara; Chico, Verónica; Mercado, Luis; Perez, Luis; Coll, Julio; Ortega-Villaizan, Maria Del Mar

2017-01-01

Background : Some fish viruses, such as piscine orthoreovirus and infectious salmon anemia virus, target red blood cells (RBCs), replicate inside them and induce an immune response. However, the roles of RBCs in the context of infectious pancreatic necrosis virus (IPNV) infection  have not been studied yet. Methods : Ex vivo rainbow trout RBCs were obtained from peripheral blood, Ficoll purified and exposed to IPNV in order to analyze infectivity and immune response using RT-qPCR, immune fluorescence imaging, flow cytometry and western-blotting techniques. Results : IPNV could not infect RBCs; however, IPNV increased the expression of the INF1-related genes ifn-1 , pkr and mx genes. Moreover, conditioned media from IPNV-exposed RBCs conferred protection against IPNV infection in CHSE-214 fish cell line. Conclusions : Despite not being infected, rainbow trout RBCs could respond to IPNV with increased expression of antiviral genes. Fish RBCs could be considered as mediators of the antiviral response and therefore targets of new strategies against fish viral infections. Further research is ongoing to completely understand the molecular mechanism that triggers this antiviral response in rainbow trout RBCs.

The offer of chemistry to targeted therapy in cancer.

PubMed

Jemel, Ikram; Jellali, Karim; Elloumi, Jihene; Aifa, Sami

2011-12-01

Cancer therapy is facing the big challenge of destroying selectively tumour cells without harming the normal tissues. Chemotherapy was trying from the beginning to kill malignant cells because of their proliferative activity since normal cells are in general quiescent. Meanwhile side effects were produced due to the destruction of some normal cells that need regular proliferation. The discovery of biomarkers led to the identification of molecular targets within tumour cells in order to kill them selectively. Chemistry followed the progress of biomarkers biotechnology by the production of target specific antagonists which were the subject of many patents. Meanwhile novel problems of tumour resistance appeared and made the battle against cancer a non stop development of new strategies and new weapons. As a consequence, paralleled activities of patenting biomarkers and chemical antagonists are continuously generated. The offer of chemistry does not actually limit the efficiency of Targeted therapy but the identification of biomarkers is still missing the exclusive specificity to tumour cells.

Antiviral screening of forty-two Egyptian medicinal plants.

PubMed

Soltan, Maha Mohamed; Zaki, Adel Kamal

2009-10-29

Egyptian medicinal plants are well known by their diverse uses in traditional folk medicine to cure various ailments including infectious diseases. Forty-two Egyptian medicinal plant species were selected from local market and were subjected to antiviral screening bioassay to investigate and to evaluate their biological activities. Hydro-alcoholic extracts of each species were separately prepared and tested against three viruses: herpes simplex-1 virus (HSV), poliomyelitis-1 virus (POLIO) and vesicular stomatitis virus (VSV). The antiviral activity were determined by means of the end point titration technique (EPTT) that depends on the ability of plant extract dilutions to inhibit the produced cytopathogenic effect (CPE) and expressed as reduction factor (Rf) of the viral titer. Achillea fragrantissima, Jasonia montana and Globularia arabica are found to have antiviral activity against POLIO in a concentration dependent manner at complete non-toxic concentration range 10-100 microg/ml (Rf 10(6)), 10-100 microg/ml (Rf 10(5)) and 50-100 microg/ml (Rf 10(4)), respectively while Tanacetum sinaicum are found to have moderate antiviral activity against POLIO at concentration of 50-100 microg/ml (Rf 10(2)). Ephedra alata and Moringa peregrina are found to have antiviral activity against HSV (Rf 10(4)). Also, the results revealed that Capparis sinaica, Tamarix nilotica and Cyperus rotundus are found to have virucidal effect against HSV. All the forty-two plant species are found to have no reliable antiviral activity against VSV. The specific indications claimed by the traditional healers are confirmed by antiviral test.

EGFR Targeted Therapies and Radiation: Optimizing Efficacy by Appropriate Drug Scheduling and Patient Selection

PubMed Central

Cuneo, Kyle C.; Nyati, Mukesh K.; Ray, Dipankar; Lawrence, Theodore S.

2015-01-01

The epidermal growth factor receptor (EGFR) plays an important role in tumor progression and treatment resistance for many types of malignancies including head and neck, colorectal, and nonsmall cell lung cancer. Several EGFR targeted therapies are efficacious as single agents or in combination with chemotherapy. Given the toxicity associated with chemoradiation and poor outcomes seen in several types of cancers, combinations of EGFR targeted agents with or without chemotherapy have been tested in patients receiving radiation. To date, the only FDA approved use of an anti-EGFR therapy in combination with radiation therapy is for locally advanced head and neck cancer. Given the important role EGFR plays in lung and colorectal cancer and the benefit of EGFR inhibition combined with chemotherapy in these disease sites, it is perplexing why EGFR targeted therapies in combination with radiation or chemoradiation have not been more successful. In this review we summarize the clinical findings of EGFR targeted therapies combined with radiation and chemoradiation regimens. We then discuss the interaction between EGFR and radiation including radiation induced EGFR signaling, the effect of EGFR on DNA damage repair, and potential mechanisms of radiosensitization. Finally, we examine the potential pitfalls with scheduling EGFR targeted therapies with chemoradiation and the use of predictive biomarkers to improve patient selection. PMID:26205191

Erythrocyte membrane-coated gold nanocages for targeted photothermal and chemical cancer therapy

NASA Astrophysics Data System (ADS)

Zhu, Dao-Ming; Xie, Wei; Xiao, Yu-Sha; Suo, Meng; Zan, Ming-Hui; Liao, Qing-Quan; Hu, Xue-Jia; Chen, Li-Ben; Chen, Bei; Wu, Wen-Tao; Ji, Li-Wei; Huang, Hui-Ming; Guo, Shi-Shang; Zhao, Xing-Zhong; Liu, Quan-Yan; Liu, Wei

2018-02-01

Recently, red blood cell (RBC) membrane-coated nanoparticles have attracted much attention because of their excellent immune escapability; meanwhile, gold nanocages (AuNs) have been extensively used for cancer therapy due to their photothermal effect and drug delivery capability. The combination of the RBC membrane coating and AuNs may provide an effective approach for targeted cancer therapy. However, few reports have shown the utilization of combining these two technologies. Here, we design erythrocyte membrane-coated gold nanocages for targeted photothermal and chemical cancer therapy. First, anti-EpCam antibodies were used to modify the RBC membranes to target 4T1 cancer cells. Second, the antitumor drug paclitaxel (PTX) was encapsulated into AuNs. Then, the AuNs were coated with the modified RBC membranes. These new nanoparticles were termed EpCam-RPAuNs. We characterized the capability of the EpCam-RPAuNs for selective tumor targeting via exposure to near-infrared irradiation. The experimental results demonstrate that EpCam-RPAuNs can effectively generate hyperthermia and precisely deliver the antitumor drug PTX to targeted cells. We also validated the biocompatibility of the EpCam-RAuNs in vitro. By combining the molecularly modified targeting RBC membrane and AuNs, our approach provides a new way to design biomimetic nanoparticles to enhance the surface functionality of nanoparticles. We believe that EpCam-RPAuNs can be potentially applied for cancer diagnoses and therapies.