The Frederick National Lab and Moffitt Cancer Center have established a collaboration to research antibody responses against the human papillomavirus (HPV) in males following administration of the Gardasil vaccine. The vaccine prevents HPV infections that can cause a number of cancers, including oral cancers.
HPVs—especially HPV 16—cause approximately 70 percent of cancers of the oral cavity, which are on the rise and are disproportionately higher among males, according to the Centers for Disease Control and Prevention. In 2020, the number of males with HPV-related oral cancer is expected to exceed the number of females with HPV-related cervical cancer.
At present, no routine screening methods exist for oral cancers, making it difficult to identify these malignancies when they are most amenable to treatment. Two approaches to reducing the HPV-related oral cancer burden are possible: development of new and effective screening tests, and primary prevention through HPV vaccination.
The Cooperative Research and Development Agreement with the Moffitt Cancer Center aims to better understand the mechanisms of protection elicited by the vaccine at relevant sites of infection, specifically the oral cavity in males. Ligia Pinto, Ph.D., HPV Immunology Laboratory, is collaborating with Anna Giuliano, Ph.D., at the Moffitt Cancer Center in Tampa, Fla., the only NCI-designed comprehensive cancer center in Florida as well as one of the nation’s top-rated cancer centers.
“The focus of the collaborative research with Dr. Giuliano is to support the extension of the benefits of HPV vaccination in the primary prevention of oral HPV infection, ultimately preventing HPV-related oral cancer among men,” Pinto said.
Each year, approximately 14 million people become infected with HPV. About 15 types of HPV cause cancer. The Food and Drug Administration has approved three prophylactic vaccines that protect against different combinations of virus strains: the quadrivalent vaccine (HPV 6, 11, 16, 18) Gardasil, the bivalent vaccine (HPV 16, 18) Cervavix, and the nonavalent vaccine, Gardasil 9 (HPV 6, 11, 16, 18, 31, 33, 45, 52, 59). The quadrivalent and bivalent vaccines have shown outstanding immunogenicity and long-term efficacy against HPV infection and pre-cancerous lesions.
While young girls have been advised to get the Gardasil or Cervarix vaccine against HPV 16 and 18 to prevent cervical cancer, they are not the only ones affected by the virus. HPV has been shown to cause approximately 70 percent of oral cancers in both genders, but primarily in men.
Recently, Giuliano and others have demonstrated that the Gardasil vaccine, directed against HPV 6, 11, 16, and 18, effectively protects against those strains as well as the subsequent development of HPV-related external genital lesions and anal disease in young males (ages 16–26 years). This work led to the licensure of Gardasil for males ages 9–26 for the prevention of HPV 6- and 11-related genital warts and HPV 16- and 18-related anal cancer. But HPV measurements in tissues lining the mouth and upper areas of the throat were not included; therefore, there are no data to support the prevention of oral cancer, and there are no trials underway as of yet to evaluate this possibility.
Despite the existence of three effective vaccines, coverage remains low. In the United States, four out of ten teenage females and six out of ten teenage males are not vaccinated against HPV, leaving them at risk for HPV infections, according to the CDC. For this reason, the CDC is ramping up public education on the vaccine in an effort to lower the burden of HPV, regardless of gender.
Currently, the HPV vaccine is given in three doses over six months. However, recent research suggests that women who received one, two, or three doses of the Cervarix vaccine were all protected against the virus. This suggests that one or two doses may be just as effective as the standard three doses.
Fewer doses would make immunization against HPV in developing countries with limited health care and long commutes to the doctor’s office more feasible and convenient for everyone. The ultimate goal—a single effective dose—could reduce cases of cervical cancer worldwide while saving both time and money.
Image: An image of a koilocyte shows human ectocervical cells expressing HPV-16 E5 oncoprotein, and immortalized with HPV-16 E6 and E7 oncoproteins. Formation of koilocytes requires cooperation between HPV E5 and E6 oncoproteins. The cell culture is stained with hematoxylin and eosin. Image courtesy of the National Cancer Institute.
Last updated: June 10, 2016