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1
VIRUSES AND CANCER
Bidasari Lubis Child Heatlh Departement University of
Sumatera Utara - Medan
Introduction
• Relationship between human oncogenic viruses and cancer werw established mostly in last quarter of the 20th century.
• Virus infection : second major preventable cancer risk factor after tobacco use
• Immunization program againts HBV in
Taiwan, Gambia succesfully lowered HCC . • HPV vaccine (2006) reduced death cervical
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2 Introduction
Virus implicated 15% of all cancer: 1. Nasopharyngeal carcinoma 2. Burkitt’s lymphoma
3. Cervical carcinoma 4. T-cell leukemia
5. Hepatocellular carcinoma 6. Kaposi’s sarcoma
Observation viruses may cause cancer
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3 Human oncogenic viruses
• Hepatitis B virus (HBV) • Hepatitis C virus (HCV)
• Human Papilloma virus (HPV) • Epstein-Barr Virus (EBV)
• Kaposi’s sarcoma – associated Herpesvirus (KSHV)
• Human T-cell Leukemia virus-1 (HTLV-1)
Mechanisms of virus –induced cellular transformation
The oncogenic mechanism used by different viruses differ significantly.
1. Perturbation of signaling pathways 2. Deregulation of the cell cycle
3. Escape of apoptosis 4. Immrotalization of cells
5. Induction of genetic instability 6. Insertional mutagenesis
