Vaccine strategies for human papillomavirus-associated cancers

Purpose of review: To review novel immunologic strategies for the prevention and treatment of human papillomavirus infection and associated diseases. Both animal model systems and human protocols are discussed. Recent findings: Many vaccine platforms for both prevention of human papillomavirus infection and treatment of associated disease have been developed. Virus-like particle constructs containing human papillomavirus capsid proteins have been shown to protect against human papillomavirus infection. Novel peptide or protein constructs containing modified E6 or E7 proteins, novel adjuvants, fusion proteins such as immunoglobulin-G-heavy chain E7, or heat shock proteins have been made as therapeutic modalities. In addition, many new recombinant vaccine vectors such as vaccinia, Listeria species, adenovirus, Semliki Forest vectors, and others have been developed as carriers of immunotherapeutic agents. Recently, chimeric virus-like particle vaccines have been developed to treat existing human papillomavirus-induced neoplasms. Summary: Immunotherapy protocols using a variety of recombinant vectors and modified human papillomavirus proteins induce in-vitro T cell responses and may lead to tumor regression. Vaccine-induced in-vitro immune reactivity and clinical vaccine effects are often not well associated. Further analysis of ongoing human immunotherapy trials is awaited.