HPV Flashcards
1
Q
Virus associated cancers
- What % of cancers are associated with virus infections?
- What are the most common virus-associated cancers in females?
- What are the most common virus associated cancers in males?
A
- 10-20
- Cervical Cancers
- Liver cancers (HBV, HCV)
2
Q
Name the Viruses Associated with Human Cancer:
- Retroviridae
- Papillomaviridae
- Hepadnaviridae
- Flaviviridae
- Herpesviridae
- What % of human cervical cancer is associated with papillomaviruses?
A
- HTLV1
- HPV
- HBV
- HCV
- Kaposi’s sarcoma associated herpesvirus
(EBV can also cause cancer) - 99%
3
Q
Virus associated cancers
- How long do the viruses last/infect?
- How do these cancers vary?
- Is the virus enough to cause cancer?
- What part of the virus is found in the tumor cells?
- How do other viruses contribute to cancer formation?
A
- persistently infecting, last many years
- vary geographically and culturally
- no; viruses far more common than the tumors they cause
- genome
- may cause immunosuppression –> cancer growth (HIV)
4
Q
HPV Structure
- Envelope?
- genome
- What is the capsid made of? how does it arrange?
A
- no
- double strand DNA, circular
- L proteins (L1 is predominant); self assembly into pentameric units
5
Q
HPV Genome
- What is the promoter of the L gene products?
- Where is the promoter for the E gene products?
A
- L2 proximal promoter
2. promoter near LCR
6
Q
HPV in epithelium
- What is made first? genome or capsule?
- What occurs in the basal keratinocytes?
- What occurs in the spinosum?
- What occurs in the Granulosum?
- What occurs in the Corneum?
- How stable is HPV in the environment?
A
- Genome
- HPV infects cell; injects viral DNA
- HPV genome replication
- Virions mature
- dead epithelial cells are loaded with virions, which are spread when they desquamate?
- VERY stable; can survive in the environment
7
Q
HPV
- Gross manifestation
- Where could is be clinically significant?
- Time course between inoculation and gross manifestation?
- How long does it take to resolve? Why?
- When does cell transformation occur?
A
- usually a wart
- if the wart is in an airway
- months
- years to never; HPV is in the skin, which immune cells have a hard time reaching
- rarely, after infection of the basal cells
8
Q
HPV integration
- What happens to viral production after HPV is integrated into host genome?
- What gene is “broken”?
- What 2 genes are intact?
- What does not occur if the 2 genes in (3) are broken?
A
- no more viral production
- E2
- E6 and E7
- cancer does not develop if E6 and E7 are broken
9
Q
HPV Cancer
- Where can it spread?
- What do the cells look like?
- When can it develop?
- HPV transmission
A
- local metastasis; can go to nearby lymph nodes, rarely spreads beyond pelvis
- highly vacuolated; haloes around shrunken nuclei;
- years after HPV infection
- Sexually
10
Q
HPV Diagnosis
- Does it grow in culture?
- What does (1) mean?
- How is it diagnosed/categoried?
- What is looked for by (3)? why?
- Is dysplasia required for the test in (3) to pick up HPV?
A
- no
- hard to categorize via serology
- DNA; RNA in Situ Hybridization
- E6 and E7; latently infected cells will make those transcripts
- No
11
Q
HPV
- What does cell sense when viral DNA replicates?
- What happens?
- What does virus need to do?
- How does it do this?
A
- senses damaged DNA,
- cell increases p53 and Rb to stop the cell from dividing and cause cell death; cell is trying to prevent cancer
- Needs to deplete p53 and Rb so that it can continue to replicate
- produces E6 and E7
12
Q
- How does E6 reduce the amount of p53?
2. What does E7 bind to?
A
- E6 and an adapter protein ubiquinates p53 many times; this leads to degradation of p53 and continued replication of the cell
- p105RB
13
Q
HPV Vaccine
- What is it made of?
- What does it contain?
- How is it given?
- What % of cervical cancer does it protect against?
A
- Virus-like particles
- four HPV VLPs (6, 11, 16, 18)
- 3 injections
- 70% of cervical cancer
