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How HPV Contributes to Cervical Cancer. Research suggests that most cervical cancers develop when certain genetic HPV strains activate certain oncogenes (cancer-causing genes). These oncogenes interfere with certain protective proteins, which normally limit cell growth. Once they are blocked, cell growth can accelerate, leading to tumor development and cancer.
HPV Genetic Types. There are more than 100 types of HPV. More than 30 genetic variants of human papillomaviruses can be passed through sexual contact from one person to another. People initially infected by one type of HPV are still at risk for infection from other types.
Low-risk HPV types, such as HPV 6 and 11, cause genital warts and cervical intraepithelial neoplasia I (CIN I). High-risk HPV types can cause cervical cancer. Less commonly, high-risk HPV types can cause as well as cancers of the vagina, vulva, anus, penis, oropharyngeal (throat, tongue, soft palate) and possibly lung cancers.
Of the high-risk types, HPV types 16 and 18 are known to be particularly dangerous. These two genetic types and six others (31, 33, 35, 45, 52, and 58) account for 95% of HPV-related cervical cancers. Other high-risk types are 39, 51, 56, 59, 68, 73, and 82. All are associated with cervical intraepithelial neoplasia II (CIN II) and cervical intraepithelial neoplasia III (CIN III). Types 26, 53, and 66 are also considered high risk.
The high-risk viruses generally produce flat and nearly invisible growths, compared to the usually harmless warts caused by low-risk HPV viruses.
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Review Date: 10/21/2010
Reviewed By: Harvey Simon, MD, Editor-in-Chief, Associate Professor of Medicine,
Harvard Medical School; Physician, Massachusetts General Hospital.
Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M.,
Inc.
A.D.A.M., Inc. is accredited by URAC, also known as the American Accreditation HealthCare Commission (www.urac.org)
