HPV and Cervical Cancer
Cervical cancer is the second most common cancer in women: it kills 230,000 people each year. That’s why Cincinnati Children’s researcher Susanne Wells, PhD is working to understand all of the factors that lead to it. "We know that cervical cancer is caused by a sexually transmitted virus, called human papillomavirus," said Wells. "There’s a vaccine to prevent infection, but it is not helpful once infection has occurred."
Though the HPV vaccine is now available to girls as young as 9 years of age, Wells hopes that her research will help provide better treatment for women who already have the virus, or who do not have access to the vaccine before it is too late. Fifty percent of people who are of reproductive age are estimated to have been exposed to HPV, and over 6.2 million new cases of HPV occur each year. Of the millions who get infected, most will not develop cancer. The trick is to pinpoint what causes certain women to be at risk.
"We do not understand exactly what makes a very small proportion of infected women progress to cancer over time," said Wells. "It is hard to make connections because it often takes decades for the cancer to appear." Wells studies the genetics of cervical cancer to better understand factors that determine the outcome of HPV infection. Human genes that influence the process could help diagnose the cancer early, or could even be targets for treatment.
The virus is also more likely to lead to cancer when it produces large amounts of two viral proteins called E6 and E7. "E6 and E7 are absolutely necessary for carcinogenesis," said Wells. "If you look carefully, the cancer will almost always express E6 and E7, and if you suppress those, the cancer will die." Using tissue samples in the lab, Wells studies how E6 and E7 contribute to cancer growth and viral amplification. "They block tumor suppressing genes which are normally needed to keep cell growth under control and prevent cancer," she said. "Suppressing E6 and E7 has not been easy as a clinical approach, but is promising as a cure."
