ABSTRACT
Since December 2019, severe acute respiratory syndrome coronavirus 2 infection has spread worldwide. We all are concerned about immunocompromised children, especially hematologic and oncologic pediatric patients. We want to share our experience with 2 pediatric cancer patients with severe acute respiratory syndrome coronavirus 2 infection. Both presented mild disease and good outcome. No respiratory symptoms were identified, but both developed diarrhea, one probably secondary to lopinavir/ritonavir. Pediatric cancer patients may have milder disease than adults, but larger studies are needed to make conclusions.
Subject(s)
Coronavirus Infections/diagnosis , Kidney Neoplasms/virology , Pneumonia, Viral/diagnosis , Sarcoma, Ewing/virology , Wilms Tumor/virology , Adolescent , Betacoronavirus/isolation & purification , COVID-19 , Child , Child, Preschool , Coronavirus Infections/drug therapy , Coronavirus Infections/epidemiology , Diarrhea/etiology , Diarrhea/virology , Female , Humans , Kidney Neoplasms/epidemiology , Lopinavir/therapeutic use , Pandemics , Pneumonia, Viral/drug therapy , Pneumonia, Viral/epidemiology , Ritonavir/therapeutic use , SARS-CoV-2 , Sarcoma, Ewing/epidemiology , Spain/epidemiology , Wilms Tumor/epidemiologyABSTRACT
A tumor cell is formed when a critical amount of endogenous and/or exogenous tumorigenic stimuli is exceeded. We have shown that the transient presence of nontumorigenic stray cells in tissues of experimental animals that contain cells with a subcritical set of genetic mutations can act as a tumor-promoting stimulus. To induce somatic mutations in all chicken tissues, we have used the MAV-2 retroviral insertion system that almost exclusively generates nephroblastomas. MAV-2 mutagenized animals i.v. inoculated with nonmalignant cells developed early clonal lung tumors before nephroblastomas. Importantly, the injected cells did not become a component of resultant tumors. Lung tumors displayed specific mutational signature characterized by an insertion of MAV-2 provirus into the fyn-related kinase (frk) promoter that results in the overexpression of the frk gene. In contrast, plag1, foxP, and twist genes were most often mutagenized in nephroblastomas. Based on such observations, we propose the mechanism termed industasis, a promotion of fully malignant phenotype of incipient tumor cell by stray cells, and hypothesize that it might be the underlying cause of human multiple primary tumors.
Subject(s)
Cell Transformation, Neoplastic/pathology , Cells/pathology , Animals , Cell Movement/physiology , Cells/virology , Cells, Cultured , Chick Embryo , Chickens , Kidney Neoplasms/pathology , Kidney Neoplasms/virology , Lung Neoplasms/pathology , Lung Neoplasms/virology , Models, Biological , Mutagenesis, Insertional/physiology , Neoplasm Invasiveness , Neoplasms, Multiple Primary/etiology , Proviruses/growth & development , Proviruses/physiology , Virus Physiological Phenomena , Wilms Tumor/pathology , Wilms Tumor/virologyABSTRACT
There have been few studies regarding the etiology of renal cell carcinoma. To examine the possible involvement of Epstein-Barr virus (EBV) in this disease, 9 renal cell carcinoma (RCC), 2 nephroblastoma (Wilms' tumor) and 2 RCC cell lines were subjected to mRNA in situ hybridization and indirect immunofluorescence staining. Messenger RNA in situ hybridization using BamHIW, EBNA LP, EBNA 2 and EBER1 probes of EBV revealed signals in all the examined samples, although some samples showed weak signals using the EBNA LP probe. Indirect immunofluorescence staining using anti-EBNA LP, anti-EBNA2, anti-LMP1 and anti-BZLF1 antibodies showed definitive fluorescence. PCR also revealed EBV DNA in all 8 RCC specimens including 7 cases other than hybridization and fluorescence. EBV infected all the RCC and nephroblastoma irrespective of the histological or clinical stage. On the other hand, EBV expression was stronger in papillary and clear cell-type RCC than chromophobe cell-type, as well as being stronger in the higher grades of RCC. These results suggest that the expression of EBV may be involved in the pathogenesis of RCC and nephroblastoma.
Subject(s)
Carcinoma, Papillary/virology , Carcinoma, Renal Cell/virology , Epstein-Barr Virus Infections/virology , Kidney Neoplasms/virology , Urinary Bladder Neoplasms/virology , Wilms Tumor/virology , Adult , Aged , Carcinoma, Papillary/genetics , Carcinoma, Papillary/metabolism , Carcinoma, Renal Cell/genetics , Carcinoma, Renal Cell/metabolism , Child, Preschool , Epstein-Barr Virus Infections/genetics , Epstein-Barr Virus Infections/metabolism , Epstein-Barr Virus Nuclear Antigens/genetics , Epstein-Barr Virus Nuclear Antigens/metabolism , Female , Fluorescent Antibody Technique , Fluorescent Antibody Technique, Indirect , Herpesvirus 4, Human/isolation & purification , Humans , In Situ Hybridization , Infant , Kidney Neoplasms/genetics , Kidney Neoplasms/metabolism , Male , Middle Aged , Polymerase Chain Reaction , RNA Probes , RNA, Messenger/genetics , RNA, Messenger/metabolism , RNA, Viral/analysis , Reverse Transcriptase Polymerase Chain Reaction , Urinary Bladder Neoplasms/genetics , Urinary Bladder Neoplasms/metabolism , Wilms Tumor/genetics , Wilms Tumor/metabolismABSTRACT
Gene deregulation is a frequent cause of malignant transformation. Alteration of the gene structure and/or expression leading to cellular transformation and tumor growth can be experimentally achieved by insertion of the retroviral genome into the host DNA. Retrovirus-containing host loci found repeatedly in clonal tumors are called common viral integration sites (cVIS). cVIS are located in genes or chromosomal regions whose alterations participate in cellular transformation. Here, we present the chicken model for the identification of oncogenes and tumor suppressor genes in solid tumors by mapping the cVIS. Using the combination of inverse PCR and long terminal repeat-rapid amplification of cDNA ends technique, we have analyzed 93 myeloblastosis-associated virus type 2-induced clonal nephroblastoma tumors in detail, and mapped >500 independent retroviral integration sites. Eighteen genomic loci were hit repeatedly and thus classified as cVIS, five of these genomic loci have previously been shown to be involved in malignant transformation of different human cell types. The expression levels of selected genes and their human orthologues have been assayed in chicken and selected human renal tumor samples, and their possible correlation with tumor development, has been suggested. We have found that genes associated with cVIS are frequently, but not in all cases, deregulated at the mRNA level as a result of proviral integration. Furthermore, the deregulation of their human orthologues has been observed in the samples of human pediatric renal tumors. Thus, the avian nephroblastoma is a valid source of cancer-associated genes. Moreover, the results bring deeper insight into the molecular background of tumorigenesis in distant species.
Subject(s)
Chickens , Kidney Neoplasms/genetics , Oncogenes/genetics , Poultry Diseases/genetics , Virus Integration/genetics , Wilms Tumor/genetics , Animals , Avian Myeloblastosis Virus/genetics , Avian Proteins/genetics , Chick Embryo , Chromosome Mapping , DNA-Binding Proteins/genetics , Genes, Tumor Suppressor , Genes, ras/genetics , Humans , Kidney Neoplasms/virology , Oncogene Proteins/genetics , Polymerase Chain Reaction , Proviruses/genetics , Terminal Repeat Sequences , Twist-Related Protein 1/genetics , Wilms Tumor/virologyABSTRACT
The molecularly cloned myeloblastosis-associated virus type-1(N) (MAV-1(N)) strain induces specifically nephroblastomas in chicken. MAV-induced nephroblastoma constitutes a unique animal model of the human Wilms' tumor. We have previously shown that the MAV-1(N) long terminal repeats (LTR) were necessary and sufficient for nephroblastoma induction. Since major determinants for oncogenesis have been mapped in the U3 region of several other retroviruses, we have analyzed the tumorigenic potential of five recombinant viruses partially deleted in their U3 region. The results obtained indicated that deletions of the LTRs resulted in a modification of the pathogenic spectrum of MAV-1(N) and a decreased efficiency for nephroblastoma induction.
Subject(s)
Avian Myeloblastosis Virus/genetics , Avian Myeloblastosis Virus/pathogenicity , Gene Expression Regulation, Viral , Sequence Deletion , Terminal Repeat Sequences/genetics , Wilms Tumor/virology , Animals , Base Sequence , Chickens , Disease Models, Animal , Humans , Kidney/pathology , Kidney/virology , Molecular Sequence Data , Recombination, Genetic , Virulence , Virus Replication , Wilms Tumor/pathologyABSTRACT
Recent studies have detected simian virus 40 (SV40) DNA in certain human tumors and normal tissues. The significance of human infections by SV40, which was first discovered as a contaminant of poliovirus vaccines used between 1955 and 1963, remains unknown. The occurrence of SV40 infections in unselected hospitalized children was evaluated. Polymerase chain reaction and DNA sequence analyses were done on archival tissue specimens from patients positive for SV40 neutralizing antibody. SV40 DNA was identified in samples from 4 of 20 children (1 Wilms' tumor, 3 transplanted kidney samples). Sequence variation among SV40 regulatory regions ruled out laboratory contamination of specimens. This study shows the presence of SV40 infections in pediatric patients born after 1982.
Subject(s)
Papillomavirus Infections/diagnosis , Simian virus 40 , Tumor Virus Infections/diagnosis , Antibodies, Viral/blood , Child , DNA, Viral/analysis , Humans , Kidney Neoplasms/blood , Kidney Neoplasms/pathology , Kidney Neoplasms/virology , Kidney Transplantation , Papillomavirus Infections/blood , Papillomavirus Infections/pathology , Polymerase Chain Reaction , Retrospective Studies , Simian virus 40/genetics , Simian virus 40/isolation & purification , Tumor Virus Infections/blood , Tumor Virus Infections/pathology , Wilms Tumor/blood , Wilms Tumor/pathology , Wilms Tumor/virologyABSTRACT
The tumor suppressor protein p53 is aberrantly localized to the cytoplasm of neuroblastoma cells, compromising the suppressor function of this protein. Such tumors are experimentally induced in transgenic mice expressing the large tumor (T) antigen of polyomaviruses. The oncogenic mechanisms of T antigen include complex formation with, and inactivation of, the tumor suppressor protein p53. Samples from 18 human neuroblastomas and five normal human adrenal glands were examined. BK virus DNA was detected in all neuroblastomas and none of five normal adrenal glands by PCR. Using DNA in situ hybridization, polyomaviral DNA was found in the tumor cells of 17 of 18 neuroblastomas, but in none of five adrenal medullas. Expression of the large T antigen was detected in the tumor cells of 16 of 18 neuroblastomas, but in none of the five adrenal medullas. By double immunostaining BK virus T antigen and p53 was colocalized to the cytoplasm of the tumor cells. Immunoprecipitation revealed binding between the two proteins. The presence and expression of BK virus in neuroblastomas, but not in normal adrenal medulla, and colocalization and binding to p53, suggest that this virus may play a contributory role in the development of this neoplasm.
Subject(s)
Adrenal Gland Neoplasms/pathology , Adrenal Gland Neoplasms/virology , Adrenal Glands/virology , BK Virus/isolation & purification , Neuroblastoma/pathology , Neuroblastoma/virology , Adrenal Gland Neoplasms/genetics , Adrenal Glands/cytology , Adrenal Glands/pathology , Animals , Antigens, Viral, Tumor/analysis , Antigens, Viral, Tumor/genetics , Child , Genes, APC , Genes, p53 , Humans , Kidney Neoplasms/genetics , Kidney Neoplasms/pathology , Kidney Neoplasms/virology , Mice , Mice, Transgenic , Neuroblastoma/genetics , Polymerase Chain Reaction , Wilms Tumor/genetics , Wilms Tumor/pathology , Wilms Tumor/virologyABSTRACT
OBJECTIVES: To determine the association between malignancy and the Human Immunodeficiency Virus type 1 (HIV-1) infection in children. DESIGN: Case series. SETTING: The Paediatric Oncology Unit at Parirenyatwa Teaching Hospital. SUBJECTS: 76 consecutive newly diagnosed cases of malignancy between May 15 and November 15 1997. MAIN OUTCOME MEASURES: HIV serostatus. RESULTS: 27 out of 64 children were HIV seropositive, giving a seroprevalance rate of 42.2% (95% CI 30.1 to 54.3%). The four commonest diagnosed malignancies were non-Hodgkin's lymphoma (22.4%), acute lymphoblastic leukemia (19.7%), Wilm's tumour (19.7%) and Kaposi's sarcoma (15.8%). These tumours accounted for 77.6% of all malignancies. Nine of a total of 17 patients with non-Hodgkin's lymphoma were HIV positive and all 12 patients with Kaposi's were also HIV positive. No cases of Burkitt's lymphoma were seen. Although there was increased incidence of non-Hodgkin's lymphoma (NHL) compared to previous years, there was no significant association with the HIV serostatus. A significant association between Kaposi's sarcoma (KS) and HIV serostatus was observed (p < 0.001). Children with KS were more likely to be HIV seropositive. Children with acute lymphoblastic leukemia (ALL) and Wilm's tumours (WT) were 83 and 88% less likely to be HIV seropositive, respectively. CONCLUSIONS: HIV has transformed the pattern of childhood malignancy in Zimbabwe. The two tumours mostly affected are NHL and KS.
Subject(s)
HIV Infections/complications , HIV Seroprevalence , HIV-1 , Lymphoma, Non-Hodgkin/virology , Precursor Cell Lymphoblastic Leukemia-Lymphoma/virology , Sarcoma, Kaposi/virology , Wilms Tumor/virology , Age Distribution , Child, Preschool , Female , Hospitals, Teaching , Humans , Male , Sex Distribution , ZimbabweABSTRACT
Avian leukemias and lymphomas are caused primarily by retroviruses and herpesviruses. The protooncogenes activated by avian retroviral insertions in B & T-cell lymphomas will be summarized, with discussion on a new common insertion site, bravo, associated with RAV-O LTR insertion. Two novel interactions between avian retroviruses and Marek's disease herpesvirus (MDV) will be described: one involves direct interactions between putative viral oncoproteins and the other integrative recombination between these two viruses.
Subject(s)
Avian Leukosis/virology , Herpesviridae/genetics , Lymphoma, B-Cell/veterinary , Lymphoma, T-Cell/veterinary , Poultry Diseases , Proto-Oncogenes , Retroviridae/genetics , Alpharetrovirus/genetics , Animals , Chickens , DNA Transposable Elements , Herpesviridae/pathogenicity , Kidney Neoplasms/veterinary , Kidney Neoplasms/virology , Lymphoma, B-Cell/virology , Lymphoma, T-Cell/virology , Recombination, Genetic , Retroviridae/pathogenicity , Tumor Virus Infections/virology , Virus Integration , Wilms Tumor/veterinary , Wilms Tumor/virologyABSTRACT
Although several cytogenetic alterations have been associated with development of Wilms' tumor, a multigenic neoplasia, molecular mechanisms of its induction, development and maintenance remain to be elucided. In order to characterize these different steps we have developed a unique animal model of Wilms' tumor constituted by the MAV-1(N) induced avian nephroblastoma. This animal model led to the discovery in our laboratory of a new gene now (nephroblastoma overexpressed gene) which is overexpressed in all avian nephroblastoma. Expression of the human nov gene (novH), which is down-regulated by WT1, is also deregulated in Wilms' tumors. Nov characteristics suggest that it would play a role in the control of cellular proliferation and differentiation. Our observations also indicate that nov could be involved in the development of Wilms' tumors, and represent a marker of their differentiation state.
Subject(s)
Avian Myeloblastosis Virus/pathogenicity , Genes, Wilms Tumor , Immediate-Early Proteins , Intercellular Signaling Peptides and Proteins , Oncogene Proteins, Viral/genetics , Proto-Oncogene Proteins/genetics , Wilms Tumor/genetics , Animals , Cell Division , Cell Transformation, Neoplastic/genetics , Chick Embryo , Chromosomes, Human, Pair 11/genetics , Connective Tissue Growth Factor , Disease Models, Animal , Gene Expression Regulation, Neoplastic , Humans , Molecular Sequence Data , Nephroblastoma Overexpressed Protein , Oncogene Proteins, Viral/isolation & purification , Oncogene Proteins, Viral/metabolism , Promoter Regions, Genetic , Transcription, Genetic , Wilms Tumor/pathology , Wilms Tumor/virologyABSTRACT
The use of chimeric viruses allowed us to establish that myeloblastosis-associated virus long terminal repeat sequences are necessary and sufficient for induction of nephroblastoma in chickens and that the blastemal hyperplasia induced by env SU is not a prerequisite for tumor development but rather constitutes a predisposing stage.
Subject(s)
Avian Leukosis/virology , Avian Myeloblastosis Virus/genetics , Chickens , Genes, env/physiology , Kidney Neoplasms/veterinary , Kidney/pathology , Poultry Diseases/virology , Repetitive Sequences, Nucleic Acid/genetics , Retroviridae Infections/veterinary , Wilms Tumor/veterinary , Animals , Avian Myeloblastosis Virus/pathogenicity , Avian Sarcoma Viruses/genetics , Avian Sarcoma Viruses/pathogenicity , Chickens/virology , Hyperplasia/virology , Introns , Kidney/virology , Kidney Neoplasms/virology , Repetitive Sequences, Nucleic Acid/physiology , Retroviridae Infections/virology , Wilms Tumor/virologyABSTRACT
Myeloblastosis-associated viruses (MAV) are replication competent avian retroviruses responsible for the induction of lymphoid leukosis, osteopetrosis, and nephroblastoma. Although both the route of infection and the strain of host used has been reported to be a critical factor in determining the outcome of viral infection, genetically distinct strains of MAV that exhibit a multiple pathogenic potential have been molcularly cloned. Osteopetrosis is a proliferative disease of the bones and nephroblastoma is a kidney cancer. Both diseases occur in chickens a few weeks after MAV injection. In both cases, the nature of the target cells and mechanisms of transformation induced by MAV remain to be established. Molecular cloning and sequencing of three MAV proviral genomes inducing both osteopetrosis and nephroblastoma or only nephroblastoma have allowed the identification of viral determinants essential for osteopetrosis induction. For the last decade we have focused our attention on the MAV-induced nephroblastoma because it is a unique animal model of the human Wilms' tumor. Studies that we have conducted to understand the molecular basis of MAV tumorigenic potential have led to the identification of viral sequences required for tumor induction and to the discovery of a new cellular gene (nov) likely to play a critical role in avian and human nephroblastoma development.
Subject(s)
Avian Myeloblastosis Virus/pathogenicity , Amino Acid Sequence , Animals , Avian Leukosis/genetics , Avian Leukosis/virology , Avian Myeloblastosis Virus/genetics , Avian Myeloblastosis Virus/isolation & purification , Birds , Cloning, Molecular , Disease Models, Animal , Genes, Viral , Humans , Kidney Neoplasms/pathology , Kidney Neoplasms/veterinary , Kidney Neoplasms/virology , Molecular Sequence Data , Osteopetrosis/genetics , Osteopetrosis/veterinary , Osteopetrosis/virology , Virus Integration , Wilms Tumor/genetics , Wilms Tumor/pathology , Wilms Tumor/veterinary , Wilms Tumor/virologyABSTRACT
The avian nephroblastoma induced by myeloblastosis-associated virus constitutes a unique animal model in which to study genes involved in the initiation and progression of the human Wilms' tumor. Along this line, we have identified a new cellular gene (nov, for nephroblastoma overexpressed) whose expression is regulated in vitro by the WT1 proteins and is stimulated in all avian nephroblastomas. The nov gene is also conserved in human and its expression is altered in Wilms' tumors. In both species, the nov gene encodes a potential insulin growth factor (IGF)-binding protein associated tot he extracellular matrix and likely to be involved in cell growth regulation. The recent data that are discussed in this review strongly suggest that the nov protein might play a critical role in normal and pathological nephrogenesis.