The Dangers of HPV
By Emma and Cassie
What is oral HPV?
Is it curable?
What are the symptoms?
How is HPV spread?
What HPV proteins cause cancer?
- HPV produces the proteins E6 and E7 which shut down two important tumor suppressor proteins in normal cells. It causes p53 and Rb to deactivate and allow cells to grow out of control.
- E1 and E2 are required for DNA replication. E2 makes sure viral DNA moves into new cells during mitosis and acts as a transcriptional activator or repressor. E2 controls other E genes such as E6 and E7. As E2 increases, E6 and E7 are down regulated. This ends up in a loss of the cellular environment needed for viral DNA replication. This change in the gene expression produces more of the HPV virus. When the infected cells reach terminal differentiation its causes the genes L1 and L2 to be expressed. L1 and L2 are proteins that are produced in the second or last phase of the viral life cycle.
- HPV types 16 and 18 are responsible for the majority of HPV-caused cancers. Type 16 and 18 are responsible for about 70 percent of all cervical cancer cases. A study on HPV 16 in the US shows the amount of HPV 16 is higher in women compared to men. Most of the time in women, the infection is only temporary, but in a minority of women the HPV virus will persist. If the HPV type is 16 or 18 there is an increased risk of developing cervical cancer.
What kinds of cancers can HPV cause?
- HPV can cause many types of cancer such as cervical cancer. Cervical cancer is caused when a woman comes in contact with HPV. Her immune system usually fights off the virus and prevents it from doing serious harm. In some women the virus survives and eventually leads to the conversion of normal cells to cancerous cells in the cervix.
- HPV can also cause cancers of the vulva, vagina, penis, anus, and oropharynx (back of the throat)