Immunotherapy of HPV induced head and neck cancer (HNC)

Immunotherapy of HPV induced  HNC represents a new treatment approach that might allow clinicians to use conventional treatment at lower doses, and reduce treatment-related toxicity. Therapy is directed at  the oncoproteins E6 and E7 that are expressed by tumor cells.

Prophylactic vaccination against HPV  induces antigen-specific B cells that can  prevent initial infections. In contrast, therapeutic vaccines generate CD8+ HPV-specific T cell immune response against E6 and E7 oncoproteins. 

Their role in prevention of HPV-related oropharyngeal cancers is currently being evaluated, with one trial showing promising results.

Several vaccination therapies are under investigation in HPV-associated HNC. DNA vaccines produce non-living antigens able to induce cytotoxic T cell, and Th and B cell immunity. Several DNA vaccine trials targeting HPV are being tested in cervical cancer.

Peptide  vaccines incorporate amino acid sequences that are synthesized to form an immunogenic peptide molecule representing the specific epitope of a tumor-associated antigens that binds onto human leukocyte antigen. (http://www.ncbi.nlm.nih.gov/pubmed/14647479). Several peptide vaccines are under evaluation in HPV+ HNC..

Vaccination strategies involving Dendritic cells are also currently being assessed in HPV+ HNC. Activated DCs cells are injected back into the patient 5to kill the cancer (http://www.ncbi.nlm.nih.gov/pubmed/26351330). Several bacterial HPV vaccines targeting E6 and E7 have been developed. 

Finally, adoptive T-cell transfer (ACT) might be a promising immunotherapy strategy for HPV HNC; it involves harvesting and ex vivo expansion of the patient’s own tumor antigen specific T-cells. Subsequently, T-cells are re-introduced to the patient, with the view to enhance immunity and improve anticancer immune response.

It is hopeful that these novel immunotherapy strategies of HPV positive HNC will improve patient outcome.