1/31 Kingsley Human Papillomavirus (HPV) Flashcards
HPV structure
- dsDNA
- naked, non-enveloped virus
HPV - two major capsid proteins
L1 major and L2 minor
Since HPV is a naked virus, it can:
Survive on surfaces for a long time, withstand many conditions
L1 capsid binds to:
- Syndecan-1
- Laminin-332 (laminin-5)
- alpha 6 (a6B4) integrin
HPV entry is via:
Clathrin or caveolin-mediated endocytosis (receptor mediated endocytosis)
HPV entry via L1/L2 induces ______ to expose _____
conformational change; furin binding site
____ endosomal endoprotease cleaves ____. This exposes ____
Furin; L2; nuclear localization sequence (NLS)
HPV replication is promoted via what proteins?
Early proteins E6 and E7
HPV early E6 protein also binds (inactivates):
p53 tumor suppressor
HPV early E7 protein also binds (inactivates):
Rb (retinoblastoma)
L1 major is a:
Pentamer
L2 minor is a:
Hexamer
HPV can inactivate p53 and Rb which allows ____ bypass. The proteins responsible are termed _____
G1/S; viral oncogenes
True or false: HPV virus is not cytolytic
True
HPV virus is released by:
Degeneration of desquamating cells
HPV strains can be found in:
cutaneous or mucosal areas
Skin warts mainly caused by:
HPV 1-4
Skin (epithelial) warts are mainly found on what parts of the body?
Hands and feet (common in children, young adults)
Which HPV strains are associated with high-risk mucosal/genital infection?
16 and 18
also 31, 45, and others
Which HPV strains are associated with low-risk infection?
6 and 11
Regarding HPV, high or low risk means:
Likeliness of developing cancer as a result of HPV infection
HPV high risk strains are ____
Oncogenic
______ cause 70% of cervical cancers
HPV16 and HPV18
____ cause ____% of viral anogenital warts
HPV6 and HPV11; 90-95%
True or false: HPV is also found in the oral cavity
True
HPV strains in oral cancer may harbor:
high risk HPV 16 and HPV18
True or false: HPV is also found in breast cancers
True
HPV strains in breast cancer may harbor:
high risk HPV 16 and HPV18
How does HPV end up in breast cancers?
Oral HPV transmitted from partner (males > 90%)
Patients with ____ are at higher risk for HPV infection, such as _____
Immunodeficiency; T-cell deficiencies
One of the earliest clinical signs of HPV infection in an immunocompromised individual
Warts on hands
In HIV patients, most frequent site of oral squamous cell carcinomas is:
Tongue
Epidermodysplasia verruciformis is also known as:
Lewandowsky-Lutz dysplasia
Epidermodysplasia verruciformis is a ____ disease that causes ____ as a result of infection by ____
autosomal recessive disease; tree-like lesions; HPV5 and HPV8
HPV viral cofactor
Zinc
Epidermodysplasia verruciformis
A mutation on ____ in the ____ genes leads to ____
Chromosome 17; EVER1/2 genes; lack of regulation of zinc in nucleus
Zinc is HPV viral co-factor
Cervical cancer screening involves:
Papanicolaou-stained (Pap) smear
What HPV vaccines are available?
- Gardasil (Merck) quadrivalent
- Gardasil 9vHPV (nine-valent)
HPV Quadrivalent vaccine includes what HPV strains?
6, 11 (low risk); 16, 18 (high-risk)
HPV nine-valent vaccine includes what HPV strains?
6, 11, 16, 18, 31, 33, 45, 52, 58
Gardasil 9vHPV includes _____ for expanded use up to 45 years old
31, 33, 52, 58 (part of nine valent)
HPV vaccine reduces ____ % of cervical cancer
90%
Most important factor in reduction of cervical cancer
Age of HPV vaccination
_____ reduction in oral HPV infections with only one dose
88%
____ reduction in oral HPV infections with three doses
99%
Only ___ of dentists felt comfortable discussing HPV vaccination
51%
