ID HPV, Warts, and Cervical Cancer Flashcards
What percent of cancers are due to infectious agents?
20%
HPV causes how many deaths annually?
500,000
Describe the structure of HPV.
Non-enveloped, dsDNA virus
About _______ percent of cervical cancers and _______ percent of head and neck cancers are caused by HPV.
100; 25
Explain the difference between early and late genes.
Early genes –so named because they are transcribed early after infection –deal with replication, transformation, and transcription, while late genes –transcribed later –include capsids.
Describe the life cycle of HPV.
HPV is dependent on the proliferation of epithelial cells. It infects the undifferentiated basal layer and is secreted by the mature skin layers.
How many new cases of HPV occur per year?
6.2 million –the most common STD
Persistence of ____________ is associated with development of cancer.
high-risk HPV genotypes
Which strains are high risk?
16, 18, 31, 33, and 45
HPV 6 and 11 can cause what worrisome complication?
Laryngeal papillomatosis
Where does HPV infect women?
In the transformation zone (between the squamous epithelium of the outer cervix and the inner columnar epithelium of the inner cervix); 99% infect here
True or false: most people infected with HPV will develop persistent infections.
False. Only about 10% do.
Which two viral genes are highly expressed in cervical carcinoma?
E6 and E7 (these are oncogenes)
What do E6 and E7 do to cause cancer?
They inhibit RB and p53.
Which kind of proteins does E2F promote?
Proteins that stimulate progression from G1 to S