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1.
Medicina (Kaunas) ; 56(5)2020 May 07.
Article in English | MEDLINE | ID: mdl-32392854

ABSTRACT

The majority of pediatric patients are cured of their primary cancer with current advanced developments in pediatric cancer therapy. However, survivors often experience long-term complications from therapies for primary cancer. The delayed mortality rate has been decreasing with the effort to reduce the therapeutic exposure of patients with pediatric cancers. Our study investigates the incidence of sarcoma as second cancer in pediatric cancer survivors. We present a 9-year-old male who survived embryonal hepatoblastoma diagnosed at 22 months of age. At 4.5 years of age, he presented with a non-metastatic primitive neuroectodermal tumor (PNET) of the left submandibular area. He has no evidence of recurrence of either cancer for 51 months after finishing all chemotherapy and radiotherapy. We used the Surveillance, Epidemiology, and End Results (SEER) database to identify the current rate of second sarcomas in pediatric cancer survivors. Our literature review and large population analysis emphasize the impact of sarcoma as a second malignancy and provide help to physicians caring for pediatric cancer survivors.


Subject(s)
Cancer Survivors/psychology , Neoplasms, Second Primary/etiology , Sarcoma/complications , Child , Hepatoblastoma , Humans , Incidence , Male , Neoplasms, Second Primary/epidemiology , Neoplasms, Second Primary/psychology , Population Surveillance/methods , Risk Factors , Sarcoma/epidemiology
2.
Cancer Res ; 80(12): 2663-2675, 2020 06 15.
Article in English | MEDLINE | ID: mdl-32291317

ABSTRACT

Neuroblastoma is a childhood cancer with heterogeneous clinical outcomes. To comprehensively assess the impact of telomere maintenance mechanism (TMM) on clinical outcomes in high-risk neuroblastoma, we integrated the C-circle assay [a marker for alternative lengthening of telomeres (ALT)], TERT mRNA expression by RNA-sequencing, whole-genome/exome sequencing, and clinical covariates in 134 neuroblastoma patient samples at diagnosis. In addition, we assessed TMM in neuroblastoma cell lines (n = 104) and patient-derived xenografts (n = 28). ALT was identified in 23.4% of high-risk neuroblastoma tumors and genomic alterations in ATRX were detected in 60% of ALT tumors; 40% of ALT tumors lacked genomic alterations in known ALT-associated genes. Patients with high-risk neuroblastoma were classified into three subgroups (TERT-high, ALT+, and TERT-low/non-ALT) based on presence of C-circles and TERT mRNA expression (above or below median TERT expression). Event-free survival was similar among TERT-high, ALT+, or TERT-low/non-ALT patients. However, overall survival (OS) for TERT-low/non-ALT patients was significantly higher relative to TERT-high or ALT patients (log-rank test; P < 0.01) independent of current clinical and molecular prognostic markers. Consistent with the observed higher OS in patients with TERT-low/non-ALT tumors, continuous shortening of telomeres and decreasing viability occurred in low TERT-expressing, non-ALT patient-derived high-risk neuroblastoma cell lines. These findings demonstrate that assaying TMM with TERT mRNA expression and C-circles provides precise stratification of high-risk neuroblastoma into three subgroups with substantially different OS: a previously undescribed TERT-low/non-ALT cohort with superior OS (even after relapse) and two cohorts of patients with poor survival that have distinct molecular therapeutic targets. SIGNIFICANCE: These findings assess telomere maintenance mechanisms with TERT mRNA and the ALT DNA biomarker C-circles to stratify neuroblastoma into three groups, with distinct overall survival independent of currently used clinical risk classifiers.


Subject(s)
Gene Expression Regulation, Neoplastic , Neuroblastoma/genetics , Telomerase/metabolism , Telomere Homeostasis , Telomere/metabolism , Cell Line, Tumor , Child , Child, Preschool , Disease-Free Survival , Female , Follow-Up Studies , Humans , Infant , Male , Neoplasm Recurrence, Local , Neuroblastoma/mortality , Neuroblastoma/pathology , RNA, Messenger/isolation & purification , RNA, Messenger/metabolism , RNA-Seq , Telomerase/genetics , Telomerase/isolation & purification , Whole Genome Sequencing , X-linked Nuclear Protein/genetics , Xenograft Model Antitumor Assays
3.
Trop Med Int Health ; 25(4): 397-407, 2020 04.
Article in English | MEDLINE | ID: mdl-31872495

ABSTRACT

OBJECTIVES: To gain insight in the potential of the current pipeline for rabies to decrease the burden of disease by evaluating its relevance to high-risk countries. METHODS: Rabies-related patent documents and clinical trials were retrieved from Espacenet and the WHO ICTRP, respectively. Data were cleaned, modulated and categorised into a pre-defined set of indicators those were used for (statistical) analyses on the number of patent applications, patent quality and type of stakeholders involved for different geographical areas. RESULTS: Analysis of 583 unique patent families applied for in the period 1954-2017 showed a steep growth in the yearly number of patent applications. A significant portion of new patent applications concern Chinese patents with relatively low quality that are filed by a dispersed group of applicants. Excluding these patents, the number of patent applications has been virtually stable over the years. A shift is seen in public stakeholders becoming more prolific as patent applicants. This shift is also reflected in clinical trials; key sponsors of clinical trials include public and private stakeholders originating from high-risk rabies countries. The majority of clinical trials investigate adjustments to existing vaccines that may improve accessibility. CONCLUSION: The results show a discrepancy between the quantity and quality of rabies patent applications that reflects national patent regulations rather than real progress in decreasing the burden of disease. This is in contrast to clinical trials, which focus on incremental innovations that are tested in clinical trials but may nevertheless have a potentially strong impact in high-risk countries.


OBJECTIFS: Comprendre le potentiel du pipeline actuel pour la rage pour réduire la charge de morbidité en évaluant sa pertinence pour les pays à haut risque. MÉTHODES: Les documents de brevet liés à la rage et les essais cliniques ont été récupérés auprès de réseau Espacenet et de l'OMS ICTRP, respectivement. Les données ont été triées, modulées et classées en un ensemble prédéfini d'indicateurs qui a été utilisé pour des analyses (statistiques) sur le nombre de demandes de brevet, la qualité des brevets et le type de parties prenantes impliquées pour différentes zones géographiques. RÉSULTATS: L'analyse de 583 familles de brevets uniques déposées au cours de la période 1954-2017 a montré une forte croissance du nombre annuel de demandes de brevet. Une part importante des nouvelles demandes de brevet concerne des brevets chinois de qualité relativement faible soumises par un groupe dispersé de déposants. A l'exclusion de ces brevets, le nombre de demandes de brevet est resté pratiquement stable au fil des ans. Un changement est observé dans les acteurs publics devenant plus prolifiques en tant que demandeurs de brevet. Ce changement se reflète également dans les essais cliniques; les principaux sponsors des essais cliniques comprennent des parties prenantes publiques et privées originaires de pays à haut risque pour la rage. La majorité des essais cliniques étudient les ajustements aux vaccins existants qui pourraient améliorer l'accessibilité. CONCLUSION: Les résultats montrent un écart entre la quantité et la qualité des demandes de brevet liées à la rage qui reflète les réglementations nationales en matière de brevets plutôt que de réels progrès dans la réduction de la charge de morbidité. Cela contraste avec les essais cliniques, qui se concentrent sur des innovations incrémentales qui sont testées dans des essais cliniques mais qui peuvent néanmoins avoir un impact potentiellement fort dans les pays à haut risque.


Subject(s)
Clinical Trials as Topic , Patents as Topic , Rabies/epidemiology , China/epidemiology , Humans , Rabies/prevention & control , Rabies Vaccines , Vaccination
4.
Mol Cancer Ther ; 18(12): 2270-2282, 2019 12.
Article in English | MEDLINE | ID: mdl-31484706

ABSTRACT

Recurrent high-risk neuroblastoma is a childhood cancer that often fails to respond to therapy. Fenretinide (4-HPR) is a cytotoxic retinoid with clinical activity in recurrent neuroblastoma and venetoclax (ABT-199) is a selective inhibitor of the antiapoptotic protein B-cell lymphoma-2 (BCL-2). We evaluated activity of 4-HPR + ABT-199 in preclinical models of neuroblastoma. Patient-derived cell lines and xenografts from progressive neuroblastoma were tested. Cytotoxicity was evaluated by DIMSCAN, apoptosis by flow cytometry, and gene expression by RNA sequencing, quantitative RT-PCR, and immunoblotting. 4-HPR + ABT-199 was highly synergistic against high BCL-2-expressing neuroblastoma cell lines and significantly improved event-free survival of mice carrying high BCL-2-expressing patient-derived xenografts (PDX). In 10 matched-pair cell lines [established at diagnosis (DX) and progressive disease (PD) from the same patients], BCL-2 expression in the DX and PD lines was comparable, suggesting that BCL-2 expression at diagnosis may provide a biomarker for neuroblastomas likely to respond to 4-HPR + ABT-199. In a pair of DX (COG-N-603x) and PD (COG-N-623x) PDXs established from the same patient, COG-N-623x was less responsive to cyclophosphamide + topotecan than COG-N-603x, but both DX and PD PDXs were responsive to 4-HPR + ABT-199. Synergy of 4-HPR + ABT-199 was mediated by induction of NOXA via 4-HPR stimulation of reactive oxygen species that induced expression of ATF4 and ATF3, transcription factors for NOXA. Thus, fenretinide + venetoclax is a synergistic combination that warrants clinical testing in high BCL-2-expressing neuroblastoma.


Subject(s)
Antineoplastic Agents/therapeutic use , Bridged Bicyclo Compounds, Heterocyclic/therapeutic use , Fenretinide/therapeutic use , Neuroblastoma/drug therapy , Proto-Oncogene Proteins c-bcl-2/metabolism , Sulfonamides/therapeutic use , Animals , Antineoplastic Agents/pharmacology , Bridged Bicyclo Compounds, Heterocyclic/pharmacology , Cell Culture Techniques , Cell Line, Tumor , Disease Models, Animal , Female , Fenretinide/pharmacology , Humans , Mice , Sulfonamides/pharmacology
5.
J Mol Biol ; 428(14): 2814-31, 2016 Jul 17.
Article in English | MEDLINE | ID: mdl-27216501

ABSTRACT

The lens epithelium-derived growth factor p75 (LEDGF/p75) is a chromatin-bound protein essential for efficient lentiviral integration. Genome-wide studies have located LEDGF/p75 inside actively transcribed genes where it mediates lentiviral integration. Although its role in HIV-1 integration is clearly established, the role of LEDGF/p75-associated proteins in HIV-1 infection remains unexplored. Using protein-protein interaction assays, we demonstrated that LEDGF/p75 complexes with a chromatin-remodeling complex facilitates chromatin transcription (FACT), a heterodimer of the structure-specific recognition protein 1 (SSRP1) and the human homolog of suppressor of Ty 16 (hSpt16). Detailed analysis of the interaction of LEDGF/p75 with the FACT complex indicates that LEDGF/p75 interacts with SSRP1 in an hSpt16-independent manner that requires the PWWP domain of LEDGF proteins and the HMG domain of SSRP1. Functional characterizations demonstrate a LEDGF/p75-independent role of SSRP1 in the regulation of HIV-1 replication. shRNA-mediated partial knockdown of SSRP1 reduces HIV-1 infection, but not Murine Leukemia Virus, in human CD4(+) T cells. Similarly, SSRP1 knockdown affects infection by HIV-1-derived viruses that express genes from the viral LTR but not from an internal immediate-early CMV promoter, suggesting a role of SSRP1 in LTR-driven gene expression but not in viral DNA integration. Together, our data demonstrate for the first time the association of LEDGF proteins with the FACT complex and give further support to a role of SSRP1 in HIV-1 infection.


Subject(s)
Adaptor Proteins, Signal Transducing/metabolism , DNA-Binding Proteins/metabolism , High Mobility Group Proteins/metabolism , Intercellular Signaling Peptides and Proteins/metabolism , Transcription Factors/metabolism , Transcriptional Elongation Factors/metabolism , Virus Replication/physiology , Cell Line , Chromatin/metabolism , DNA Replication/physiology , HEK293 Cells , HIV Integrase/metabolism , HIV-1/genetics , HIV-1/metabolism , Humans , Virus Integration/physiology
6.
Soc Sci Med ; 135: 75-83, 2015 Jun.
Article in English | MEDLINE | ID: mdl-25957163

ABSTRACT

Governments of developing countries can be in a vulnerable position with respect to patent protected drugs supplied by foreign firms, if the technology cannot be licensed or independently developed by local firms. In such instances, one possible solution is to negotiate for a price-drop with the patent holder in lieu of issuing a compulsory license. The present paper develops a game theoretic model of such bargaining and shows that while compulsory licenses do not occur under complete information, they can be issued under incomplete information. The model is tested against real episodes of compulsory licenses to derive policy insight.


Subject(s)
Drug Costs/legislation & jurisprudence , Drug Industry/economics , Drugs, Essential/supply & distribution , Legislation, Drug , Licensure, Pharmacy/legislation & jurisprudence , Developing Countries , Drug Industry/legislation & jurisprudence , Game Theory , Government , Humans , International Cooperation , Licensure, Pharmacy/economics , Public Policy
7.
J Virol ; 87(5): 2496-507, 2013 Mar.
Article in English | MEDLINE | ID: mdl-23255787

ABSTRACT

Poly(ADP-ribose) polymerase 1 (PARP-1) is a cellular enzyme with a fundamental role in DNA repair and the regulation of chromatin structure, processes involved in the cellular response to retroviral DNA integration. However, the function of PARP-1 in retroviral DNA integration is controversial, probably due to the functional redundancy of the PARP family in mammalian cells. We evaluated the function of PARP-1 in retroviral infection using the chicken B lymphoblastoid cell line DT40. These cells lack significant PARP-1 functional redundancy and efficiently support the postentry early events of the mammalian-retrovirus replication cycle. We observed that DT40 PARP-1(-/-) cells were 9- and 6-fold more susceptible to infection by human immunodeficiency virus type 1 (HIV-1)- and murine leukemia virus (MLV)-derived viral vectors, respectively, than cells expressing PARP-1. Production of avian Rous-associated virus type 1 was also impaired by PARP-1. However, the susceptibilities of these cell lines to infection by the nonretrovirus vesicular stomatitis virus were indistinguishable. Real-time PCR analysis of the HIV-1 life cycle demonstrated that PARP-1 did not impair reverse transcription, nuclear import of the preintegration complex, or viral DNA integration, suggesting that PARP-1 regulates a postintegration step. In support of this hypothesis, pharmacological inhibition of the epigenetic mechanism of transcriptional silencing increased retroviral expression in PARP-1-expressing cells, suppressing the differences observed. Further analysis of the implicated molecular mechanism indicated that PARP-1-mediated retroviral silencing requires the C-terminal region, but not the enzymatic activity, of the protein. In sum, our data indicate a novel role of PARP-1 in the transcriptional repression of integrated retroviruses.


Subject(s)
Poly(ADP-ribose) Polymerases/metabolism , Retroviridae/genetics , Transcription, Genetic , Virus Replication/genetics , Animals , Avian Leukosis Virus/genetics , Avian Leukosis Virus/pathogenicity , Avian Leukosis Virus/physiology , Cell Line , Chickens , Gene Expression Regulation, Viral , Gene Knockout Techniques , HEK293 Cells , HIV-1/genetics , HIV-1/pathogenicity , HIV-1/physiology , Humans , Jurkat Cells , Leukemia Virus, Murine/genetics , Leukemia Virus, Murine/pathogenicity , Leukemia Virus, Murine/physiology , Poly (ADP-Ribose) Polymerase-1 , Poly(ADP-ribose) Polymerases/genetics , Retroviridae/pathogenicity , Retroviridae/physiology , Vesicular stomatitis Indiana virus/genetics , Vesicular stomatitis Indiana virus/pathogenicity , Vesicular stomatitis Indiana virus/physiology , Virus Integration/genetics
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