HPV - The Trigger Behind Several Cancers

Genomics Revolution

Genomics Revolution

Guest Hosts: Sheree Nobles & Joshua Gregory

Episode 47: Human Papillomavirus (HPV)

Script:

Josh- Hello everyone, and welcome to this episode of Genomics Revolution! We’re your guests hosts

today, Sheree Nobles and Joshua Gregory. Today we’ll be talking about Human Papillomavirus,

or HPV as it’s commonly known. This is a sexually transmitted infection, and to keep on topic with this year’s theme, it’s a virus.

Sheree- There isn’t a scientific name for it, so much as a bunch of scientific names, as there are over 100

different human papillomaviruses. These viruses can cause not only genital warts, but warts

elsewhere, and have even been linked to cervical cancers.

Josh- Five types of HPV were found prior to 1983, but most of those HPVs were present in animals, not

humans. HPV 6 was found by German virologist Harold zur Hausen shortly before HPV 11 was

found by the same man in 1983. Shortly after that, he found HPVs 16 and 18, which together are

present in roughly 70% of cervical cancers.

Sheree- zur Hausen was originally studying cervical cancer, and the only reason he thought to look for

viruses was because the cancer seemed to be “infectious” despite cancer not behaving the way

the should . It was when his friend, a U.S. researcher named Richard Shope, told him about a

virus in rabbits that would cause warts and cervical cancer did he think about the possibility of a

virus causing the disease.

Josh- It’s important to note that most HPVs don’t cause cancer, or any symptoms at all. More often

enough, HPV is present in a human, but does not cause any symptoms before the immune

system removes it. It’s only a few types of the virus that can stay around long enough to induce

cancer, like HPV 16 or 18. This is because the virus affects a cell’s growth cycle while trying to

reproduce, causing the cells to grow rapidly and for warts to form, and sometimes causing

tumors as well.

Sheree- This is why it’s important to understand the virus. Cervical cancer only has a 66% survival rate,

so if it can be avoided, it should be. Because HPV is so closely related to the cancer, it makes

sense that we should try to understand it completely to try and stay safe from deadly diseases.

It’s also important to realize that someone can be carrying the virus without showing any

symptoms, and could possibly transfer it to another person, spreading the virus and its

dangerous symptoms.

Josh- Not only should we understand the virus, but everyone should also get tested regularly to make

sure whether or not they’re carrying HPV. Now the virus itself isn’t too complicated. Its genome is made of double-stranded DNA in a circular formation, with a singular DNA molecule. It is roughly 7916 base pairs in length with 8 ORFs, though this data is subject to slight change between different types of HPV.

Sheree- There were three findings that we thought were really important. One, HPVs are separated into

two unofficial classifications: low and high risk. Most human papillomaviruses never cause any

symptoms, let alone serious diseases, but even still, they can be transferred between people. If

someone has a compromised immune system, an HPV that doesn’t hurt one person could hurt

them. Two, certain HPVs are much more likely to cause cervical cancer.

Josh- HPVs 16 and 18 are some of the more dangerous types of the virus you can get. Together they are

present in approximately 70% of all cervical cancer cases. This is due to their ability to target

retinoblastoma (Rb) protein families and p53 in our cells. This can induce telomerase

production, causing the cell to be unable to repair damaged DNA, a crucial task for cancer cells

to continue to survive. And last but not least, HPV is total is present in around 99.7% of cervical

cancer samples, as found in 1999 by a group of scientists including U.K. Researcher Professor

Julian Peto.

Sheree- These findings are important for several reasons. They tell us that anyone could be carrying HPV

at any time and not know it. This is a common trend among some viruses, much like the corona

virus that is currently causing an uproar. They also tell us that cervical cancer, which only has a 66% survival rate, is so closely linked to HPV that we should take every care to avoid contracting HPV. Lastly, knowing the mechanism of HPV causing cancer brings us a step closer towards finding an actual cure for existing HPV infection, not just prevention, a vaccine, or surgery.

Josh- This has been an episode of Genomics Revolution, and we thank you all for listening to us ramble

about a virus.

Sheree- We’ve had some fun recording this for you, and we hope you’ll take away from this the

importance of understanding viruses and the diseases they can cause.

Josh- This has been Josh,

Sheree- and Sheree,

Josh- and we hope you have a great day, take care!

References:

IARC Working Group on the Evaluation of Carcinogenic Risk to Humans. “Human Papillomavirus (HPV)

Infection.” Human Papillomaviruses., U.S. National Library of Medicine, 1 Jan. 1970, www.ncbi.nlm.nih.gov/books/NBK321770/.

“HPV: the Whole Story, Warts and All.” Cancer Research UK - Science Blog,

scienceblog.cancerresearchuk.org/2014/09/16/hpv-the-whole-story-warts-and-all/.

Burk, Robert D., et al. “Human Papillomavirus Genome Variants.” Virology, Academic Press, 31 Aug.

2013, www.sciencedirect.com/science/article/pii/S0042682213004388.

Liu, Ying, et al. “Whole-Genome Analysis of Human Papillomavirus Types 16, 18, and 58 Isolated from

Cervical Precancer and Cancer Samples in Chinese Women.” Scientific Reports, Nature Publishing Group UK, 21 Mar. 2017, www.ncbi.nlm.nih.gov/pmc/articles/PMC5428204/#!po=25.0000.