Worldwide, cancer viruses are estimated to cause 15 to 20 percent of all cancers in humans.
Most viral infections however, do not lead to tumor formation as several factors influence the progression from viral infection to cancer development. The hepatitis B virus (shown above) is an example of a cancer causing virus that has been linked to liver cancer in people with chronic infections. Researchers have long attempted to elucidate the role that viruses play in causing cancer. Worldwide, cancer viruses are estimated to cause 15 to 20 percent of all cancers in humans. Most viral infections however,
i-growth signals, and losing the ability to undergo apoptosis or programmed cell death. Cancer cells don't experience biological aging and maintain their ability to undergo cell division and growth. Cancer Viruses: Transformation Transformation occurs when a virus infects and genetically alters a cell. The infected cell is regulated by the viral genes and has the ability to undergo abnormal new growth. Scientists have been able to discern some commonality among viruses that cause tumors. The tumor viruses c