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Antiviral Drugs as Tools for Nanomedicine
Published in Devarajan Thangadurai, Saher Islam, Charles Oluwaseun Adetunji, Viral and Antiviral Nanomaterials, 2022
During the 20th Century, transmittable agents that can cause tumors in chickens and rabbits were identified as rous sarcoma virus (RSV). RSV was the first RNA tumour virus, and shope papillomavirus was the first DNA tumor virus studied for its oncogenic efficiency. In recent years, focus has been given to viruses that can cause human cancers. The role of viruses in human cancer led to identification and characterisation of various oncogenes and tumour-suppressor genes. With the help of these studies, a few generalised principles were deduced as:In the virally associated cancers, long latent periods follow initial infection, indicating that the viruses are not sufficient to cause cancer on their own. During this long latent period, these viruses must be able to survive in the host.The virus-induced cancers do not constitute a natural part of the viral life cycle. However, virally associated cancer cells are like dead-end streets, which are not of any advantage to the virus.The viral properties responsible for the induction of tumors often play critical roles in the life cycle of the virus.
General Biological Aspects of Oncogenesis
Published in Pimentel Enrique, Oncogenes, 2020
Among RNA viruses, some retroviruses may have oncogenic potential in either natural or experimental conditions. Retroviruses are characterized by the presence of a gene encoding reverse transcriptase and may be of either exogenous or endogenous origin. There have been two types of exogenous transforming retroviruses described, namely, acute transforming retroviruses and chronic transforming retroviruses.240 Acute transforming retroviruses are characterized by the presence of specific transforming sequences, termed oncogenes. These sequences are not of viral but of cellular origin and acute transforming retroviruses act only as oncogene transducers, although they are not infectious agents transmitting malignant diseases under natural conditions. Only by means of experimental manipulations can the high oncogenic capability of actue transforming retroviruses be demonstrated. A prototype of these viruses is the Rous sarcoma virus (RSV), which was isolated from tumors of chickens.241
Notes on Cancer
Published in Nate F. Cardarelli, The Thymus in Health and Senescence, 2019
Cultivation of normal cells with Rous sarcoma virus leads to a 40 to 70% increase in RNA, with no change in the quantity of DNA.432 Rous sarcoma virus, though, may interact with other viruses as well as the genetic mechanism of the infected cell so that mechanisms involved are difficult to sort out.433
Respiratory syncytial virus infection and the need for immunization in Korea
Published in Expert Review of Vaccines, 2023
Hye Young Kim, Ki Wook Yun, Hee Jin Cheong, Eun Hwa Choi, Hoan Jong Lee
No vaccines against RSV are currently available. Several vaccines are under development and further information is provided in Section 8. Passive immunization is possible using palivizumab, a humanized murine monoclonal antibody directed against the F membrane protein. When administered monthly throughout the RSV season it can reduce the risk of hospitalization and serious complications in high-risk children and has been shown to be safe [46]. The American Academy of Pediatrics (AAP) guidelines recommend it is used in infants in the first year of life who were born premature (≤29 weeks gestational age), or have chronic lung disease of prematurity, CHD, or neuromuscular disorders; it may also be considered for those aged <2 years who are immunocompromised [47]. The Korean National Health Insurance Service indicates that candidates for palivizumab include high-risk preterm infants (those born at <32 weeks of gestation and aged ≤6 months during the October–March RSV season or those born at <36 weeks of gestation during the RSV season who have older siblings), as well as patients with bronchopulmonary dysplasia or HS-CHD aged <2 years [48]. More recently, nirsevimab, a long-acting monoclonal antibody directed against the F protein, has been approved in some countries for the prevention of RSV LRTI in infants after it was shown to be efficacious at preventing medically attended RSV-associated LRTIs in healthy late-preterm and term infants [49].
Prevention of viral infections in solid organ transplant recipients in the era of COVID-19: a narrative review
Published in Expert Review of Anti-infective Therapy, 2022
Paraskevas Filippidis, Julien Vionnet, Oriol Manuel, Matteo Mombelli
RSV is a single-stranded RNA virus that belongs to the Paramyxoviridae family and is responsible for seasonal annual epidemics worldwide. While classically observed in healthy children aged 2 years or less, RSV infections may also occur in children or adult SOT recipients, with a lower incidence than influenza virus, but a similar clinical presentation [56]. In addition to avoidance measures, the RSV-specific humanized monoclonal antibody pavilizumab is the only effective preventive treatment currently approved [88]. Prophylaxis with pavilizumab is currently recommended for high-risk children aged 2 years or less [89]. Pavilizumab is commonly used among pediatric SOT recipients, especially for heart and lung transplants [90,91], although data in the SOT setting are lacking [63]. No approved vaccines for the prevention of RSV are currently available.
Reexamining the role of tissue inflammation in radiation carcinogenesis: a hypothesis to explain an earlier onset of cancer
Published in International Journal of Radiation Biology, 2021
The avian sarcoma virus can induce fibrosarcomas in chickens and induce malignant transformations in various avian cells cultured in vitro, which is attributed to the function of v-jun gene. Transgenic mice that carry the H2 promoter-associated v-jun gene may look normal but they form wound-related fibrosarcomas after a long delay in repairing an induced wound (Schuh et al. 1990). These results are reminiscent of the results observed when using the Rous sarcoma virus (RSV). The infection of chick embryos with RSV does not affect normal development and leads to the formation of chickens, but fibrosarcomas can be induced at the location of a wound in the RSV-bearing chickens (Dolberg et al. 1985). Interestingly, injection of TGF-β can mimic the conditions present in an induced wound (Sieweke et al. 1990). These results indicate that tissue dynamics can override dormant or quiescent conditions.