Oncogenic virus ppt

About Cancer

1. ONCOGENIC VIRUS 1 A Concise Presentation By Mr. Deepak Sarangi M.Pharm

2. Introduction Discovery of viruses History What is cancer How viruses cause cancer Growth of cancer cells Classification of oncogenic virus Mechanism of oncogenic virus Drugs used to treat oncogenic viruses Precautions to prevent infection during cancer treatment Conclusion References 2 CONTENTS

3. An oncovirus is a virus that can cause cancer. This term originated from studies of acutely transforming retroviruses in the 1950–60s, often called oncornaviruses to denote their RNA virus origin. Now refers to any virus with a DNA or RNA genome causing cancer and is synonymous with "tumor virus" or "cancer virus". The vast majority of human and animal viruses do not cause cancer, probably because of long-standing coevolution between the virus and its host. 3 INTRODUCTION

4. Worldwide, the WHO International Agency for Research on Cancer estimated that in 2002, 17.8% of human cancers were caused by infection, with 11.9% being caused by one of seven different viruses. The importance of this is that these cancers might be easily prevented through vaccination (e.g., papillomavirus vaccines), diagnosed with simple blood tests, and treated with less-toxic antiviral compounds. 4 CONT ...

5. 1908: Vilhelm Ellerman and Olaf Bang, University of Copenhagen, first demonstrated that avian sarcoma leukosis virus could be transmitted after cell-free filtration to new chickens, causing leukemia. 1933: Richard Edwin Shope discovered cottontail rabbit papillomavirus or Shope papillomavirus, the first mammalian tumor virus. 1957: Sarah Stewart and Bernice Eddy discovered polyoma virus. 5 DISCOVERY OF VIRUSES

6. 1964: Anthony Epstein, Bert Achong and Yvonne Barr identify the first human oncovirus from Burkitt lymphoma cells. A herpesvirus, this virus is formally known as human herpesvirus 4 but more commonly called Epstein-Barr Virus or EBV. 1980: Human T-lymphotropic virus 1 (HTLV I), the first human retrovirus was discovered by Bernard Poiesz and Robert Gallo at NIH and Mistuaki Yoshida and coworkers in Japan. 2008: Chang and Moore, now at the University of Pittsburgh Cancer Institute, developed a new method to identify cancer viruses based on computer subtraction of human sequences from a tumor transcriptome, called digital transcriptome subtraction (DTS). 6 DISCOVERY OF HUMAN ONCOVIRUSES

7. The theory that cancer could be caused by a virus began with the experiments of Oluf Bang and Vilhelm Ellerman in 1908 who first show that avian erythroblastosis (a form of chicken leukemia) could be transmitted by cell-free extracts. This was subsequently confirmed for solid tumors in chickens in 1910-1911 by Peyton Rous. By the early 1950s it was known that viruses could remove and incorporate genes and genetic material in cells. It was suggested that these new genes inserted into cells could make the cell cancerous. Many of these viral oncogenes have been discovered and identified to cause cancer. 7 HISTORY

8. Cancer results from alterations in critical regulatory genes that control cell proliferation, differentiation, and survival. Studies of tumor viruses revealed that specific genes (called oncogenes) are capable of inducing cell transformation, thereby providing the first insights into the molecular basis of cancer. 8 WHAT IS CANCER

9. The viral agents causing cancer in eukaryotic animals by integrating in host genome. A virus associated with malignancies in natural host, experimental animals or cell cultures. viruses which modified proto- oncogene, obligatory host specific, with the ability immortalization, possess genes which stimulate growth and cause cancer. 9 HOW VIRUSES CAUSE CANCER

10. 10 GROWTH OF CANCER CELLS

11. Classification 11

12. Human papilloma virus (HPV), a DNA virus, causes transformation in cells through interfering with tumor suppressor proteins such as p53. Kaposi's sarcoma-associated herpesvirus (KSHV or HHV-8) is associated with Kaposi’s sarcoma, a type of skin cancer. Epstein-Barr virus (EBV or HHV-4) is associated with four types of cancers. Merkel cell polyomavirus – a polyoma virus – is associated with the development of Merkel cell carcinoma . Human cytomegalovirus (CMV or HHV-5) is associated with mucoepidermoid carcinoma and possibly other malignancies. 12 DNA ONCOGENIC VIRUSES

13. Not all oncoviruses are DNA viruses. Some RNA viruses have also been associated such as the hepatitis C virus as well as certain retroviruses, e.g., human T-lymphotropic virus (HTLV-1) and Rous sarcoma virus (RSV). 13 RNA ONCOGENIC VIRUSES

14. Virus Percent of cancers Associated cancer types Hepatitis viruses, including hepatitis B (HBV) and hepatitis C (HCV) 4.9 Hepatocellular carcinoma (liver cancer ). Human T-lymphotropic virus (HTLV) 0.03 Adult T-cell leukemia Human papillomaviruses (HPV) 5.2 Cancers of cervix , anus , penis , vulva/vagina , and oropharyngeal cancer . Kaposi’s sarcoma-associated herpesvirus (HHV-8) 0.9 Kaposi’s sarcoma, multicentric Castleman's disease and primary effusion lymphoma Merkel cell polyomavirus Not available Merkel cell carcinoma Epstein–Barr virus (EBV) Not available Burkitt’s lymphoma, Hodgkin’s lymphoma, Post-transplant lymphoproliferative disease and Nasopharyngeal carcinoma . 14

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16. 16 MECHANISM OF ONCOGENIC VIRUS

17. 17 DRUGS USED TO TREAT ONCOGENIC VIRUSES

18. Wash your hands after using the bathroom, blowing your nose, coughing, or sneezing. Wash your hands after touching animals, collecting trash, or taking out garbage. Use moist cleaning wipes to clean surfaces and things that you touch, such as door handles, ATM or credit card keypads, and any items that are used by other people. Stay away from anyone with a fever, the flu, or other infection. 18 PRECAUTIONS TO PREVENT INFECTION DURING CANCER TREATMENT

19. Do not wade, play, or swim in ponds, lakes, rivers, or water parks. Wear shoes all the time — in the hospital, outdoors, and at home. This helps you avoid injury and keep germs off your feet. Do not keep fresh flowers or live plants in your bedroom. Use hot water to clean your dishes. 19 CONT…

20. Globally, almost 20% of cancers are related to infection agents. Several viruses with oncogenic potential stimulate cell proliferation and cause tumors and cancer in animals and humans. They act with different mechanisms depending on different factors. The tumor viruses with small genomes  integrate into host cell chromosomal DNA and cause mutations and chromosomal rearrangements that predispose to cancer. The oncogenic DNA and RNA viruses that are carrying oncogenes encode transforming proteins to stimulate tumor formation. 20 CONCLUSION

21. Murat ŞEVİK, Laboratory of Molecular Microbiology, Veterinary Control Institute, Konya – TURKEY, Oncogenic viruses and mechanism of oncogenesis, 2012; 36(4): pg. no.323-329. Parkin, Donald Maxwell (2006). "The global health burden of infection-associated cancers in the year 2002". International Journal of Cancer, 118 (12): pg. no.3030–44. Oncovirus , from wikipedia, the free encyclopedia. 21 REFERENCES

22. 22 THANKS for viewing the ppt For more ppts on pharma related topics plz contact [email protected] Or find me at following link www.facebook.com/sarangi.dipu