Author: Belinda Lin
Editors: Angela Pan and He-Hanson Xuan
Artist: Serena Zhou
Human Papillomavirus, often referred to as HPV, has a reputation for being a sexually transmitted infection (STI) that causes warts known as papilloma. There are over 200 strains of HPV, of which HPV-16 is the most commonly correlated with cancer due to carcinogenesis in its disease pathology, and thus is categorized as an oncovirus.
While 80% of Americans contract HPV in their lifetime, 90% clear their infections. The 10% usually result in head and neck cancers (HNC), particularly oropharyngeal cancer (OPC), of which 90% of those diagnosed result from HPV-16 infection.
How does HPV enter our bloodstreams? HPV first attaches itself to the basement membrane, above the dermis of the skin, by entering the body through wounds or microbe abrasions from sexual activity. At the basement layer, HPV attaches to the heparan sulphate receptors (HSR), infiltrating the basal cells. This allows the HPV to inject DNA into the cell's nucleus. As the basal cell matures, the infected cells make their way to the top, under the epidermis layer, allowing the cell to proliferate and replicate the virus. During this process, HPV lies low, preventing the expression of its genes, and avoiding immune response until later in the cycle.
The way HPV-16 causes cancer is through infecting a stem cell within the basal cell layer. As the stem cells mature, HPV takes over the receptors of the host cell to continue replicating. During replication, these oncoviruses will express genes called E6 and E7, preventing the body from activating tumor suppression proteins known as p5 and the retinoblastoma protein (pRb). This allows cancer cells to continue replicating. Thus, it is critical to understand the long-term effects of what seems to be a simple viral infection that would go away.
Citation:
Commissioner, Office of the. “HPV (Human Papillomavirus).” U.S. Food and Drug
Administration, FDA, https://www.fda.gov/consumers/women/hpv-human-
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“HPV and Cancer.” American Cancer Society, https://www.cancer.org/healthy/cancer-
causes/infectious-agents/hpv/hpv-and-cancer-info.html.
“Std Facts - Human Papillomavirus (HPV).” Centers for Disease Control and Prevention,
Centers for Disease Control and Prevention, 12 Apr. 2022,
https://www.cdc.gov/std/hpv/stdfact-hpv.htm.
“What Is HPV and How Is It Transmitted? - Blog: Everlywell: Home Health Testing Made
Easy.” Everlywell, https://www.everlywell.com/blog/hpv/what-is-hpv/.
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