Lecture 27

Question 1

What is HPV and what diseases does it cause?

Answer 1

Human papiloma virus. Most common viral infection of the reproductive tract. Most infections are asymptomatic and 90% resolve within 2 years. A small proportion persists and progresses to pre-cancerous lesions, and if untreated, lead to cancer

Question 2

How many types of HPV are there? How many cause cancer?

Answer 2

>100 types of HPV

At least 13 are oncogenic (cause cancer)

Question 3

Ongogenic HPV is mainly transmitted how?

Answer 3

Through sexual contact

Question 4

What are the two cancer causing genes encoded in the HPV genome?

Answer 4

E6 and E7

Question 5

How does an HPV infection lead to cancer?

Answer 5

HPV infects the squamous cells in the cervix. In mild cases, only a few cells are affected and this sometimes goes away on its own. In moderate cases, affected cells are found throughout much of the lining of the cervix. These abnormal cells progress to malignancy after the virus slips two key cancer-causing genes into the DNA of the host.

Question 6

What is the effect of the virus derived ongogenes on the human genes?

Answer 6

Virus derived oncogenes inactivate host-derived tumour suppressor genes pRB and p53. This causes an outgrowth of de-regulated cells.

Question 7

What 2 things are required for HPV to progress to cancer?

Answer 7

1. persistent infection
2. integration into the host genome and increased expression of virus-encoded oncogenes E6 and E7

Question 8

What % of cervical cancers are caused by HPV?

Answer 8

99%

Question 9

HPV types 16 and 17 cause what % of cervical cancers?

Answer 9

70%

Question 10

HPV can cause what other types of cancers?

Answer 10

Anal, vuval, vaginal, penile, and oropharyngeal cancers

70-90% of newly diagnosed oropharylgeal cancers in the USA are HPV positive

Question 11

What vaccine prevents HPV?

Answer 11

Gardasil

Question 12

What part of the virus is in the HPV vaccine?

Answer 12

HPV L1 antigen

Question 13

What types of HPV does GARDASIL-9 protect against?

Answer 13

6, 11 (wart causing)

16, 18, 31, 33, 45, 52, 58 (oncogenic)

Question 14

How is the HPV vaccine created?

Answer 14

L1 proteins produced in recombinant yeast and self-assemble into VLPs (capsule protein but no nucleic acid)

Question 15

What adjuvant is included in the HPV vaccine?

Answer 15

Amorphous aluminium hydroxyphosphate sulphate (AAHS)

Question 16

What were the cervical cancer disparities between Maori and non-Maori people?

Answer 16

Maori females had a cervical cancer registratio rate twice that of non-Maori females

Mortality rate for Maori females were 2.5x as high compared to non-Maori females (bc they were diagnosed much later than non-Maori females)

Question 17

How has the HPV vaccine programme affected the Maori community?

Answer 17

HPV vaccine programme has

• explicitly prioritised Maori
• engaged with Maori stakeholders nationally and regionally and used Maori equity advisory groups to guide the design and roll out to DHBs
• made service and delivery to young Maori women effective
• funding to target maori women
• ensuring uptake

Question 18

Why were Maori women less likely to get the HPV vaccine before the vaccine programme?

Answer 18

Awareness and understanding of HPV vaccine was lower amongst Maori parents than Pakeha parents

Mothers made the decisions for Pakeha women, wider whanau made decisions for Maori women

Pakeha parents tended to delay the decisions until the daughters were more mature

Maori tended to follow advice from a trusted source rather than from written information