Cancer and viruses: A double‐edged sword

Abstract

Oncovirus, synonymously called a 'tumour virus', is a virus that can cause cancer. An oncolytic virus preferentially infects the host's cancer cells and lyses them, causing tumour destruction, and is thus referred to as a 'cancer killing virus'. With an estimated 11% of cancer-associated deaths caused by oncoviruses and the possibility that many cancers may be treated by using oncolytic viruses, the role of viruses in cancer may be viewed as a double-edged sword. A total of seven human cancer viruses have been identified as oncoviruses, having been associated with various cancers. Conversely, a large number of oncolytic viruses have shown great potential towards the treatment of certain types of cancer. Proteomics has now been applied towards understanding the complex interplay that exists between oncoviruses and the immune responses that serve to prevent oncoviral diseases. This review attempts to summarise the neoplastic potential of human tumour associated viruses and associated vaccine successes. The potential use of oncolytic viruses for the therapeutic intervention of cancer will also be discussed. Finally, this review will discuss the enormous potential of proteomics technology in the field of oncovirology.

Persistent viremia by a novel parvovirus in a slow loris (Nycticebus coucang) with diffuse histiocytic sarcoma

“…The number of recognized oncogenic viruses is increasing and nowadays several examples—both from the human and animal fields—are well characterized. The best known examples are the papillomaviruses causing cervical cancers in humans and different types of genital and cutaneous cancers in aquatic mammals, the hepadnaviruses causing hepatocellular carcinomas in humans and woodchucks, the Epstein Barr virus which is responsible for Burkitt's lymphoma or retroviruses which are at the origin of different types of malignancies in humans and other mammals (McAloose and Newton, 2009 ; Braoudaki and Tzortzatou-Stathopoulou, 2011 ; Butt and Miggin, 2012 ; Pannone et al, 2014 ). It is therefore very important to identify novel oncoviruses and extensively study them in order to understand their tumorigenic mechanisms, especially in light of future developments such as prevention strategies.…”

“…It is reasonable to believe that the Sl.L-PV-1 was not the cause of the malignancy but merely found the ideal replication condition in cancer cells since, as discussed above, it is well known that parvoviruses need actively replicating cells (S-phase) in order to proliferate (Berns, 1990 ). In fact it is known that certain viruses, called oncolytic viruses, have tropism for specific cancer cells and they can even lead to “spontaneous regression” of malignancies (Butt and Miggin, 2012 ; Sze et al, 2013 ). This has been proven for the adeno-associated dependoparvovirus , although in an indirect way by enhancing adenoviral replication, and for a rodent parvovirus (Nüesch et al, 2012 ; Laborda et al, 2013 ).…”

Role of Angiopoietins in Development of Cancer and Neoplasia Associated with Viral Infection

“…Infection accounts for over 15% of all cancers [108], with viral infection being a leading cause of infection-associated cancers [109][110][111]. A number of viruses have been identified as oncogenic viruses that can directly transform normal cells into malignant tumor cells.…”

Immunostimulators and Immunomodulators in Cancer Treatment

“…38 Viruses such as Newcastle disease virus and reovirus have a natural affinity for cancer cells that further aids the selectivity of these agents. The benefits of this approach are that it causes direct cytotoxicity in tumor cells and the subsequent viral-mediated lysis triggers a more potent immune activation within the tumor.…”

“…41 Viruses used as oncolytic therapy are attenuated versions of the wild-type virus. 38,39 Talimogene laherparevec is an oncolytic HSV that is engineered to encode GM-CSF. On the other hand, tumor cells are not able to mount this same response.…”