Human papillomavirus infection and the primary and secondary prevention of cervical cancer

Abstract

A wealth of evidence has led to the conclusion that virtually all cases of cervical cancer are attributable to persistent infection by a sub-set of HPV types, especially HPV16 and HPV18. These HPVs also cause a proportion of other cancers, including vulvar, vaginal, anal, penile, and oropharyngeal cancers. Although cervical cancer screening, primarily via the Pap smear, has reduced the incidence of this cancer in industrialized countries, cervical cancer remains the second most common cause of death from cancer in women worldwide, as the developing world has lacked the resources for widespread high quality screening. In addition to advances in Pap smear technology, identification of HPV as the etiologic agent has produced two recent advances that may have a major impact on approaches to reduce the incidence of this disease. The first is development of a preventive vaccine whose current versions appear to prevent close to 100% of persistent genital infection and disease caused by HPV16 and HPV18; future second generation vaccines may be able to protect against oncogenic infections by a broader array of HPV types. The second is the incorporation of HPV testing into screening programs. In women over 30, HPV testing can identify high grade dysplasias earlier than Pap smears, with acceptable rates of specificity. These results, together with the high sensitivity of HPV testing, imply that such testing could permit increased intervals for screening. An inexpensive HPV test in development might, if successful, be incorporated as part of an economically viable “screen-and-treat” approach in the developing world. The manner in which vaccination and screening programs are integrated will need to be carefully considered, so they can efficiently reduce the overall incidence of cervical cancer.

A Cryo-Electron Microscopy Study Identifies the Complete H16.V5 Epitope and Reveals Global Conformational Changes Initiated by Binding of the Neutralizing Antibody Fragment

“…HPV16 is the most prevalent high-risk type of HPV (4,5) and has been a primary target for the development of prophylactic vaccines (6,7). HPV is epitheliotropic, and its replication is tightly associated with terminal differentiation of keratinocytes.…”

Suppression of STAT-1 Expression by Human Papillomaviruses Is Necessary for Differentiation-Dependent Genome Amplification and Plasmid Maintenance

“…The high-risk HPVs are causative agents of cervical cancers and are associated with cancers of the vulva, vagina, anus, and penis as well as the oral cavity. Prior to the development of cancers, HPVs establish persistent infections in the genital tract that successfully evade immune clearance (3,25,30).HPVs infect stratified epithelia and establish their doublestranded DNA genomes as episomes that are replicated in a differentiation-dependent manner (28). During their productive life cycles, these viruses escape host innate immune surveillance as well the adaptive responses through mechanisms that are not fully understood.…”

“…Over 120 HPV types have been identified, and about 30% of HPVs infect the genital epithelia. These genital HPV types are further classified as either high risk (e.g., HPV16, -18, -31, and -35) or low risk (e.g., HPV6 and -11) according to their association with genital cancers (25,30). The high-risk HPVs are causative agents of cervical cancers and are associated with cancers of the vulva, vagina, anus, and penis as well as the oral cavity.…”

“…The high-risk HPVs are causative agents of cervical cancers and are associated with cancers of the vulva, vagina, anus, and penis as well as the oral cavity. Prior to the development of cancers, HPVs establish persistent infections in the genital tract that successfully evade immune clearance (3,25,30).…”

Prevention of human papillomavirus (HPV) infection and cervical cancer in China: How does HPV vaccination bring about benefits to Chinese women?

“…Human papillomavirus (HPV) infection acquired from sexual activities is the most common viral infection of the reproductive tract and the causal relationship between HPV infection and the cervix and cervical cancer was built by zur Hausen, the Nobelist in Physiology and Medicine in 2008 for his epoch-making findings. The infection can be detected in more than 95% of carcinoma issues (2). So far, more than 100 different HPV genotypes have been detected, and among them type 16,18,31,33,35,39,45,51,52,56,58,59, and 68 are a high-risk for cervical carcinoma.…”