viral cancers?

Question

Why are human cancers considered VIRAL in nature?

Answer 1

Not all human cancers are considered viral in nature. But scientist have proven that people who have been exposed to certain types of viruses such as HPV (which causes genital warts) are at higher risk for certain cancer (in case of HPV, people can get Cervical cancer).

Answer 2

Human cancers are not directly viral in nature. Viruses propagate by infecting healthy cells, making them sick. Cancers propagate by the rapid, uncontrolled division of sick cells.

However, in the process of infection some viruses make their host more susceptible to tumor formation. That is because many of the supressors of tumor formation (p53 etc) must be shut down by the virus for them to take over the cell.

The previous answer is correct, viruses did show preliminary promise for curing cancers and genetic disease in lower mammals (typically rats, mice, and goats). However, higher mammals (people) have much more complicated protection mechanisms. As a result of this and perhaps other unrecognized factors, no viral-based gene therapy has ever passed clinical trials (many have failed).

Answer 3

There is a theory that posits all human cancers as having viral causes, but I think you mean that the cancer hijacks the cellular machinery in a similar fashion to viruses. The cell is on a deranged mitotic ride and ignores orders to " suicide "..

Answer 4

The good news about the role that viruses play in carcinogenesis is that vaccines now hold great promise in preventing and treating cancer. Indeed, vaccines against HPV and HBV may decrease the global cancer incidence by 15%; the vaccine for HBV has already had a major impact on the rates of hepatocellular carcinoma. Researchers also are working to develop vaccines for HIV-1 and EBV, as well as for HCV.

Furthermore, viruses may also be used to deliver gene therapy to patients with cancer and other illnesses. At M. D. Anderson, Dr. Bresalier and his colleagues are studying the use of viruses as vectors to deliver tumor necrosis factor directly to esophageal adenocarcinomas. “The idea is that this will spread the agent within the tumor and cause either necrosis of the tumor or sensitize the tumor to radiation treatment,” said Dr. Bresalier.

“I think the wave of the future is how viruses can be supportive in therapy,” said Dr. Samaniego. “We are looking for effective ways of preventing lymphoma and other cancers, so I think a lot of what you will see in the next few years is going to be [using viruses as therapy]. It is going to be a low-cost modality that is applicable worldwide.”


reff:http://www2.mdanderson.org/depts/oncolog/articles/04/1-jan/1-04-2.html

Answer 5

They aren't. Only a very few human cancers are viral.

Cervical cancer comes to mind.