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Spencer L, Olawuni B, Singh P. Gut Virome: Role and Distribution in Health and Gastrointestinal Diseases. Front Cell Infect Microbiol 2022; 12:836706. [PMID: 35360104 PMCID: PMC8960297 DOI: 10.3389/fcimb.2022.836706] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2021] [Accepted: 02/10/2022] [Indexed: 12/11/2022] Open
Abstract
The study of the intestinal microbiome is an evolving field of research that includes comprehensive analysis of the vast array of microbes – bacterial, archaeal, fungal, and viral. Various gastrointestinal (GI) diseases, such as Crohn’s disease and ulcerative colitis, have been associated with instability of the gut microbiota. Many studies have focused on importance of bacterial communities with relation to health and disease in humans. The role of viruses, specifically bacteriophages, have recently begin to emerge and have profound impact on the host. Here, we comprehensively review the importance of viruses in GI diseases and summarize their influence in the complex intestinal environment, including their biochemical and genetic activities. We also discuss the distribution of the gut virome as it relates with treatment and immunological advantages. In conclusion, we suggest the need for further studies on this critical component of the intestinal microbiome to decipher the role of the gut virome in human health and disease.
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Izi S, Youssefi M, Mohammadian Roshan N, Azimian A, Amel Jamehdar S, Zahedi Avval F. Higher detection of JC polyomavirus in colorectal cancerous tissue after pretreatment with topoisomerase I enzyme; colorectal tissue serves as a JCPyV persistence site. Exp Mol Pathol 2021; 123:104687. [PMID: 34592199 DOI: 10.1016/j.yexmp.2021.104687] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2021] [Revised: 09/11/2021] [Accepted: 09/22/2021] [Indexed: 11/30/2022]
Abstract
BACKGROUND The JC polyomavirus has been blamed to contribute in colorectal cancer (CRC), however, the topic is still controversial. Varying detection rate of JCPyV genome has been reported mainly due to technical reasons. Here, we provide summative data on the topic, with emphasize on technical issues. METHODS Formalin-fixed paraffin-embedded tissue samples from 50 patients with CRC, consisting of tumoral and non-cancerous marginal tissue (totally 100 samples) were included in the study. After DNA extraction, specific JCPyV T-Ag sequences were targeted using Real-time PCR. To unwind the supercoiled JCPyV genome, pretreatment with topoisomerase I, was applied. Immunohistochemical (IHC) staining was performed using an anti-T-Ag monoclonal antibody. RESULTS In the first attempts, no samples were found to be positive in Real-time PCR assays. However, JCPyV sequences were found in 60% of CRC tissues and 38% of non-cancerous colorectal mucosa after application of pre-treatment step with topoisomerase I enzyme (P = 0.028). T-Ag protein was found in the nuclear compartment of the stained cells in IHC assays. CONCLUSIONS The presence of JCPyV in CRC tissues, as well as T-Ag localization in the nucleolus, where its oncogenic effect takes place, may provide supporting evidence for JCPyV involvement in CRC development. The study highlights the importance of using topoisomerase I to enhance JCPyV genome detection. Also, colorectal tissue is one of the permissive human tissue for JC resistance after preliminary infection.
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Affiliation(s)
- Samira Izi
- Department of Clinical Biochemistry, School of Medicine, Mashhad University of Medical Sciences, Mashhad, IRAN; Student Research Committee, School of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Masoud Youssefi
- Department of Microbiology and Virology, School of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran; Antimicrobial resistance Research Center, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Nema Mohammadian Roshan
- Department of Pathology, School of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Amir Azimian
- Department of Pathobiology and Laboratory Sciences, North Khorasan University of Medical Sciences, Bojnourd, Iran
| | - Saeid Amel Jamehdar
- Department of Microbiology and Virology, School of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran; Antimicrobial resistance Research Center, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Farnaz Zahedi Avval
- Department of Clinical Biochemistry, School of Medicine, Mashhad University of Medical Sciences, Mashhad, IRAN.
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Massimino L, Lovisa S, Antonio Lamparelli L, Danese S, Ungaro F. Gut eukaryotic virome in colorectal carcinogenesis: Is that a trigger? Comput Struct Biotechnol J 2020; 19:16-28. [PMID: 33363706 PMCID: PMC7750180 DOI: 10.1016/j.csbj.2020.11.055] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2020] [Revised: 11/24/2020] [Accepted: 11/28/2020] [Indexed: 02/07/2023] Open
Abstract
The human gut microbiota is composed of bacteria and viruses that might be associated with colorectal cancer (CRC) onset and progression. Indeed, although viral infections have been reported to be the primary trigger in many diseases, the role of eukaryotic viruses populating the gut mucosa during early colorectal carcinogenesis is underinvestigated. Human eukaryotic viruses in the gut were found to induce alterations of the immune homeostasis so that some viral-dependent mechanisms likely able to induce DNA alterations in the bowel wall have been proposed, although no demonstration is available yet. However, thanks to the latest advancements in computational biology and the implementation of the bioinformatic pipelines, the option of establishing a direct causative link between intestinal virome and CRC will be possible soon, hopefully paving the way to innovative therapeutic strategies blocking or reverting the CRC pathogenesis.
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Affiliation(s)
- Luca Massimino
- Department of Biomedical Sciences, Humanitas University, Pieve Emanuele, Milan, Italy
| | - Sara Lovisa
- IBD Center, Laboratory of Gastrointestinal Immunopathology, Humanitas Clinical and Research Center, Rozzano, Milan, Italy
| | | | - Silvio Danese
- Department of Biomedical Sciences, Humanitas University, Pieve Emanuele, Milan, Italy
- IBD Center, Laboratory of Gastrointestinal Immunopathology, Humanitas Clinical and Research Center, Rozzano, Milan, Italy
| | - Federica Ungaro
- Department of Biomedical Sciences, Humanitas University, Pieve Emanuele, Milan, Italy
- IBD Center, Laboratory of Gastrointestinal Immunopathology, Humanitas Clinical and Research Center, Rozzano, Milan, Italy
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Gock M, Kordt M, Matschos S, Mullins CS, Linnebacher M. Patient-individual cancer cell lines and tissue analysis delivers no evidence of sequences from DNA viruses in colorectal cancer cells. BMC Gastroenterol 2020; 20:260. [PMID: 32762707 PMCID: PMC7409650 DOI: 10.1186/s12876-020-01404-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/28/2019] [Accepted: 07/28/2020] [Indexed: 12/15/2022] Open
Abstract
Background Several DNA viruses are highly suspicious to have oncogenic effects in humans. This study investigates the presence of potentially oncogenic viruses such as SV40, JCV, BKV and EBV in patient-derived colorectal carcinoma (CRC) cells typifying all molecular subtypes of CRC. Methods Sample material (gDNA and cDNA) of a total of 49 patient-individual CRC cell lines and corresponding primary material from 11 patients, including normal, tumor-derived and metastasis-derived tissue were analyzed for sequences of SV40, JVC, BKV and EBV using endpoint PCR. In addition, the susceptibility of CRC cells to JCV and BKV was examined using a long-term cultivation approach of patient-individual cells in the presence of viruses. Results No virus-specific sequences could be detected in all specimens. Likewise, no morphological changes were observed and no evidence for viral infection or integration could be provided after long term CRC cell cultivation in presence of viral particles. Conclusions In summary, the presented data suggest that there is no direct correlation between tumorigenesis and viral load and consequently no evidence for a functional role of the DNA viruses included into this analysis in CRC development.
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Affiliation(s)
- Michael Gock
- Department of General Surgery, University of Rostock, Rostock, Germany
| | - Marcel Kordt
- Department of General Surgery, Molecular Oncology and Immunotherapy, University of Rostock, Schillingallee 35, D-18057, Rostock, Germany
| | - Stephanie Matschos
- Department of General Surgery, Molecular Oncology and Immunotherapy, University of Rostock, Schillingallee 35, D-18057, Rostock, Germany
| | - Christina S Mullins
- Department of General Surgery, Molecular Oncology and Immunotherapy, University of Rostock, Schillingallee 35, D-18057, Rostock, Germany
| | - Michael Linnebacher
- Department of General Surgery, Molecular Oncology and Immunotherapy, University of Rostock, Schillingallee 35, D-18057, Rostock, Germany.
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Abstract
Colorectal cancer (CRC) is a leading cause of cancer-related deaths in both the USA and the world. Recent research has demonstrated the involvement of the gut microbiota in CRC development and progression. Microbial biomarkers of disease have focused primarily on the bacterial component of the microbiome; however, the viral portion of the microbiome, consisting of both bacteriophages and eukaryotic viruses, together known as the virome, has been lesser studied. Here we review the recent advancements in high-throughput sequencing (HTS) technologies and bioinformatics, which have enabled scientists to better understand how viruses might influence the development of colorectal cancer. We discuss the contemporary findings revealing modulations in the virome and their correlation with CRC development and progression. While a variety of challenges still face viral HTS detection in clinical specimens, we consider herein numerous next steps for future basic and clinical research. Clinicians need to move away from a single infectious agent model for disease etiology by grasping new, more encompassing etiological paradigms, in which communities of various microbial components interact with each other and the host. The reporting and indexing of patient health information, socioeconomic data, and other relevant metadata will enable identification of predictive variables and covariates of viral presence and CRC development. Altogether, the virome has a more profound role in carcinogenesis and cancer progression than once thought, and viruses, specific for either human cells or bacteria, are clinically relevant in understanding CRC pathology, patient prognosis, and treatment development.
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Esmailzadeh N, Ranaee M, Alizadeh A, Khademian A, Saber Amoli S, Sadeghi F. Presence of JC Polyomavirus in Nonneoplastic Inflamed Colon Mucosa and Primary and Metastatic Colorectal Cancer. Gastrointest Tumors 2019; 7:30-40. [PMID: 32399463 DOI: 10.1159/000504293] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/15/2019] [Accepted: 10/20/2019] [Indexed: 12/24/2022] Open
Abstract
Background Despite decades of epidemiologic and histopathologic investigations, the association between JC polyomavirus (JCPyV) infection and colorectal cancer (CRC) remains controversial. Objective This study tested the presence of JCPyV sequences and determined the viral load in a series of colorectal samples from Iranian patients. In total, 223 formalin-fixed paraffin-embedded samples from patients diagnosed with primary and metastatic CRC as well as with nonneoplastic inflamed colon mucosa were analyzed by quantitative real-time PCR for the presence of JCPyV large tumor antigen (LT-Ag) sequences. Results JCPyV LT-Ag sequences were detected in 18.6% of the CRC tissues and in 15.5% of the nonneoplastic control group. Viral LT-Ag was quantified in 18/100 primary colon adenocarcinomas, 2/10 metastatic adenocarcinomas, and 1/3 primary adenocarcinomas of the rectum. Two JCPyV-positive metastatic tumors presented a negative test result for JCPyV in the corresponding primary tumor. The median JCPyV LT-Ag copy number was 64 × 10<sup>-2</sup> per cell and 14 × 10<sup>-2</sup> per cell in the CRC cases and the nonneoplastic samples, respectively. There was no statistically significant difference between the two study groups regarding median LT-Ag DNA load (p = 0.059). Among the JCPyV-positive samples, the LT-Ag DNA load was higher in 2 metastatic tumors (from a patient with lung metastasis: 232 × 10<sup>-2</sup> copies per cell; from a patient with liver metastasis: 121 × 10<sup>-2</sup> copies per cell). Conclusions The detection of JCPyV DNA at low copy numbers (lower than 1 viral copy per cell equivalent) and the absence of viral sequences in the corresponding primary tumors of the JCPyV-positive metastatic samples weaken the hypothesis of an etiological role of JCPyV in primary CRC induction.
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Affiliation(s)
- Nadia Esmailzadeh
- Department of Microbiology, Tehran Medical Sciences, Islamic Azad University, Tehran, Iran
| | - Mohammad Ranaee
- Department of Pathology, School of Medicine, Babol University of Medical Sciences, Babol, Iran
| | - Ahad Alizadeh
- Metabolic Diseases Research Center, Qazvin University of Medical Sciences, Qazvin, Iran
| | - Aynaz Khademian
- Student Research Committee, School of Medicine, Babol University of Medical Sciences, Babol, Iran
| | - Saghar Saber Amoli
- Student Research Committee, School of Medicine, Babol University of Medical Sciences, Babol, Iran
| | - Farzin Sadeghi
- Cellular and Molecular Biology Research Center, Health Research Institute, Babol University of Medical Sciences, Babol, Iran
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Sarvari J, Mahmoudvand S, Pirbonyeh N, Safaei A, Hosseini SY. The Very Low Frequency of Epstein-Barr JC and BK Viruses DNA in Colorectal Cancer Tissues in Shiraz, Southwest Iran. Pol J Microbiol 2019; 67:73-79. [PMID: 30015427 DOI: 10.5604/01.3001.0011.6146] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/01/2017] [Indexed: 12/11/2022] Open
Abstract
Viruses including Epstein-Barr virus (EBV), JCV and BKV have been reported to be associated with some cancers. The association of these viruses with colorectal cancers remains controversial. Our objective was to investigate their infections association with adenocarcinoma and adenomatous polyps of the colon. Totally, 210 paraffin-embedded tissue specimens encompassing 70 colorectal adenocarcinoma, 70 colorectal adenomatous and 70 colorectal normal tissues were included. The total DNA was extracted, then qualified samples introduced to polymerase chain reaction (PCR). The EBV, JCV and BKV genome sequences were detected using specific primers by 3 different in-house PCR assays. Out of 210 subjects, 98 cases were female and the rest were male. The mean age of the participants was 52 ± 1.64 years. EBV and JCV DNA was detected just in one (1.42%) out of seventy adenocarcinoma colorectal tissues. All adenomatous polyp and normal colorectal tissues were negative for EBV and JCV DNA sequences. Moreover, all the patients and healthy subjects were negative for BKV DNA sequences. The results suggested that EBV and JCV genomes were not detectable in the colorectal tissue of patients with colorectal cancer in our population. Hence, BKV might not be necessitated for the development of colorectal cancer. The findings merit more investigations.
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Affiliation(s)
- Jamal Sarvari
- Department of Bacteriology and Virology, School of Medicine, Shiraz University of Medical Sciences,Shiraz,Iran.,Gastroenterohepatology Research Center, Shiraz University of Medical Sciences,Shiraz,Iran
| | - Shahab Mahmoudvand
- Department of Bacteriology and Virology, School of Medicine, Shiraz University of Medical Sciences,Shiraz,Iran
| | - Neda Pirbonyeh
- Department of Bacteriology and Virology, School of Medicine, Shiraz University of Medical Sciences,Shiraz,Iran.,Burn and Wound Healing Research Center - Microbiology Department - Shiraz University of Medical Sciences,Shiraz,Iran
| | - Akbar Safaei
- Department of Pathology, School of Medicine, Shiraz University of Medical Sciences,Shiraz
| | - Seyed Younes Hosseini
- Department of Bacteriology and Virology, School of Medicine, Shiraz University of Medical Sciences,Shiraz,Iran
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Charostad J, Astani A, Goudarzi H, Faghihloo E. DNA methyltransferases in virus-associated cancers. Rev Med Virol 2018; 29:e2022. [PMID: 30511446 DOI: 10.1002/rmv.2022] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2018] [Revised: 10/24/2018] [Accepted: 10/24/2018] [Indexed: 12/19/2022]
Abstract
Human tumor viruses are either casually linked or contribute in the development of human cancers. Viruses can stimulate oncogenesis through affecting diverse biological pathways in human cells. Growing data have demonstrated frequent involvement of one of the most characteristic parts of cellular epigenetic machinery, DNA methylation, in the oncogenesis. DNA methylation of cellular genes is catalyzed by DNA methyltransferases (DNMTs) as a key effector enzyme in this process. Dysregulation of DNMTs can cause aberrant gene methylation in promoter of cancer-related genes including tumor suppressor genes, resulting in gene silencing. In this regard, the role of tumor viruses is remarkable. Here, in this review, we used published information to elucidate whether tumor viruses are able to manipulate DNMT regulation, and if so, what are its consequences in the process of oncogenesis. This essay also aims to shed light on which cellular pathways have been engaged by viruses to induce DNMTs.
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Affiliation(s)
- Javad Charostad
- Department of Virology, School of Medicine, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran.,Student Research Committee, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran
| | - Akram Astani
- Zoonotic Diseases Research Center, School of Public Health, Sahid Sadoughi University of Medical Sciences, Yazd, Iran.,Department of Microbiology, Shahid Sadoghi University of Medical Science, Yazd, Iran
| | - Hossein Goudarzi
- Department of Microbiology, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Ebrahim Faghihloo
- Department of Microbiology, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
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Druliner BR, Ruan X, Sicotte H, O'Brien D, Liu H, Kocher JPA, Boardman L. Early genetic aberrations in patients with sporadic colorectal cancer. Mol Carcinog 2017; 57:114-124. [PMID: 28926134 DOI: 10.1002/mc.22738] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2016] [Revised: 09/01/2017] [Accepted: 09/18/2017] [Indexed: 01/10/2023]
Abstract
Chromosome instability (CIN) is widely observed in both sporadic and hereditary colorectal cancer (CRC). Defects in APC and WNT signaling are primarily associated with CIN in hereditary CRC, but the genetic causes for CIN in sporadic CRC remain elusive. Using high-density SNP array and exome data from The Cancer Genome Atlas (TCGA), we characterized loss of heterozygosity (LOH) and copy number variation (CNV) in the peripheral blood, normal colon, and corresponding tumor tissue in 15 CRC patients with proficient mismatch repair (MMR) and 24 CRC patients with deficient MMR. We found a high frequency of 18q LOH in tumors and arm-specific enrichment of genetic aberrations on 18q in the normal colon (primarily copy neutral LOH) and blood (primarily copy gain). These aberrations were specific to the sporadic, pMMR CRC. Though in tumor samples genetic aberrations were observed for genes commonly mutated in hereditary CRC (eg, APC, CTNNB1, SMAD4, BRAF), none of them showed LOH or CNV in the normal colon or blood. DCC located on 18q21.1 topped the list of genes with genetic aberrations in the tumor. In an independent cohort of 13 patients subjected to Whole Genome Sequencing (WGS), we found LOH and CNV on 18q in adenomatous polyp and tumor tissues. Our data suggests that patients with sporadic CRC may have genetic aberrations preferentially enriched on 18q in their blood, normal colon epithelium, and non-malignant polyp lesions that may prove useful as a clinical marker for sporadic CRC detection and risk assessment.
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Affiliation(s)
- Brooke R Druliner
- Division of Internal Medicine, Department of Gastroenterology and Hepatology, Mayo Clinic, Rochester, Minnesota
| | - Xiaoyang Ruan
- Biomedical Statistics and Informatics, Department of Health Sciences Research, Mayo Clinic College of Medicine, Rochester, Minnesota
| | - Hugues Sicotte
- Biomedical Statistics and Informatics, Department of Health Sciences Research, Mayo Clinic College of Medicine, Rochester, Minnesota
| | - Daniel O'Brien
- Biomedical Statistics and Informatics, Department of Health Sciences Research, Mayo Clinic College of Medicine, Rochester, Minnesota
| | - Hongfang Liu
- Biomedical Statistics and Informatics, Department of Health Sciences Research, Mayo Clinic College of Medicine, Rochester, Minnesota
| | - Jean-Pierre A Kocher
- Biomedical Statistics and Informatics, Department of Health Sciences Research, Mayo Clinic College of Medicine, Rochester, Minnesota
| | - Lisa Boardman
- Division of Internal Medicine, Department of Gastroenterology and Hepatology, Mayo Clinic, Rochester, Minnesota
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Louten J, Beach M, Palermino K, Weeks M, Holenstein G. MicroRNAs Expressed during Viral Infection: Biomarker Potential and Therapeutic Considerations. Biomark Insights 2016; 10:25-52. [PMID: 26819546 PMCID: PMC4718089 DOI: 10.4137/bmi.s29512] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2015] [Revised: 10/22/2015] [Accepted: 10/24/2015] [Indexed: 12/13/2022] Open
Abstract
MicroRNAs (miRNAs) are short sequences of noncoding single-stranded RNAs that exhibit inhibitory effects on complementary target mRNAs. Recently, it has been discovered that certain viruses express their own miRNAs, while other viruses activate the transcription of cellular miRNAs for their own benefit. This review summarizes the viral and/or cellular miRNAs that are transcribed during infection, with a focus on the biomarker and therapeutic potential of miRNAs (or their antagomirs). Several human viruses of clinical importance are discussed, namely, herpesviruses, polyomaviruses, hepatitis B virus, hepatitis C virus, human papillomavirus, and human immunodeficiency virus.
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Affiliation(s)
- Jennifer Louten
- Department of Molecular and Cellular Biology, Kennesaw State University, Kennesaw, GA, USA
| | - Michael Beach
- Department of Molecular and Cellular Biology, Kennesaw State University, Kennesaw, GA, USA
| | - Kristina Palermino
- Department of Molecular and Cellular Biology, Kennesaw State University, Kennesaw, GA, USA
| | - Maria Weeks
- Department of Molecular and Cellular Biology, Kennesaw State University, Kennesaw, GA, USA
| | - Gabrielle Holenstein
- Department of Molecular and Cellular Biology, Kennesaw State University, Kennesaw, GA, USA
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The potential for fungal biopesticides to reduce malaria transmission under diverse environmental conditions. Curr Nutr Rep 2015. [PMID: 26792946 DOI: 10.1007/s13668-012-0032-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The effectiveness of conventional malaria vector control is being threatened by the spread of insecticide resistance. One promising alternative to chemicals is the use of naturally-occurring insect-killing fungi. Numerous laboratory studies have shown that isolates of fungal pathogens such as Beauveria bassiana can infect and kill adult mosquitoes, including those resistant to chemical insecticides.Unlike chemical insecticides, fungi may take up to a week or more to kill mosquitoes following exposure. This slow kill speed can still reduce malaria transmission because the malaria parasite itself takes at least eight days to complete its development within the mosquito. However, both fungal virulence and parasite development rate are strongly temperature-dependent, so it is possible that biopesticide efficacy could vary across different transmission environments.We examined the virulence of a candidate fungal isolate against two key malaria vectors at temperatures from 10-34 °C. Regardless of temperature, the fungus killed more than 90% of exposed mosquitoes within the predicted duration of the malarial extrinsic incubation period, a result that was robust to realistic diurnal temperature variation.We then incorporated temperature sensitivities of a suite of mosquito, parasite and fungus life-history traits that are important determinants of malaria transmission into a stage-structured malaria transmission model. The model predicted that, at achievable daily fungal infection rates, fungal biopesticides have the potential to deliver substantial reductions in the density of malaria-infectious mosquitoes across all temperatures representative of malaria transmission environments.Synthesis and applications. Our study combines empirical data and theoretical modelling to prospectively evaluate the potential of fungal biopesticides to control adult malaria vectors. Our results suggest that Beauveria bassiana could be a potent tool for malaria control and support further development of fungal biopesticides to manage infectious disease vectors.
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Monaco MCG, Major EO. Immune System Involvement in the Pathogenesis of JC Virus Induced PML: What is Learned from Studies of Patients with Underlying Diseases and Therapies as Risk Factors. Front Immunol 2015; 6:159. [PMID: 25972864 PMCID: PMC4412132 DOI: 10.3389/fimmu.2015.00159] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2014] [Accepted: 03/24/2015] [Indexed: 12/16/2022] Open
Abstract
The human polyomavirus JC PyV lytic infection of oligodendrocytes in the human brain results in the demyelinating disease progressive multifocal leukoencephalopathy, PML. JCV is a common virus infection in the population that leads to PML in patients with underlying diseases and therapies that cause immune deficiencies or modulate immune system functions. Patients may have high levels of antibody to JCV that neither protect them from PML nor clear the infection once PML is established. Cell-mediated immunity plays a more effective role in clearing initial or reactivated JCV infection before PML occurs. However, patients with underlying diseases and therapies for treatment are at high risk for PML. MS patients on natalizumab are one of the categories with the highest incidence of PML. Natalizumab is a humanized monoclonal antibody targeting α4 integrins that prevents inflammatory cells from entering the brain and it has been used as a treatment for MS. A number of studies have investigated the occurrence of PML in these patients and their cell-mediated immune profile that might gain insight into the mechanism that ties natalizumab with a high risk of developing PML. It seems that cells of the immune system participate in the pathogenesis of PML as well as clearance of JCV infection.
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Affiliation(s)
- Maria Chiara G Monaco
- Laboratory of Molecular Medicine and Neuroscience, National Institute of Neurological Disorders and Stroke, National Institutes of Health , Bethesda, MD , USA
| | - Eugene O Major
- Laboratory of Molecular Medicine and Neuroscience, National Institute of Neurological Disorders and Stroke, National Institutes of Health , Bethesda, MD , USA
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13
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Abstract
Despite the monumental success of childhood prophylactic vaccination, there is no similar program designed to provide protection as we age against adult onset diseases like breast cancer. Instead, the predominant focus of current cancer vaccine strategy is to vaccinate after the tumors become established. This strategy has at best provided incremental improvement in overall survival. We propose the development of an adult vaccination program modeled on the childhood program that provides protection against diseases we confront as we enter our middle age. Since most cases of adult cancers are not associated with definitive etiopathogenic viruses, we propose extending our selection of vaccine targets to tissue-specific self proteins that are over-expressed in developing tumors but are no longer expressed in normal tissues ('retired or former self'), are expressed in normal tissues under readily avoidable conditions ('conditional self'), or are incapable of targeting any clinically significant autoimmune complications ('irrelevant self'). By extending prophylactic vaccination to such "functional non-self" targets, prophylactic vaccination against adult onset diseases like breast cancer may occur safely in the absence of any autoimmune inflammatory complications and may potentially reduce disease incidence in a manner that mimics the impact of childhood vaccination on diseases like measles and polio.
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Affiliation(s)
- Vincent K Tuohy
- Department of Immunology, Lerner Research Institute, Cleveland Clinic, Ohio, USA.
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