Cancer vaccines: emphasis on pediatric cancers

The success that vaccines have had in the fight with infectious diseases has not been mirrored in their use in the fight against cancer. The major differences are that cancer vaccines have been tested in the therapeutic rather than the prophylactic setting, and in older adults rather than in the pediatric population. Cancers, as well as current standard treatments, are highly immunosuppressive, which further compromises the success of therapeutic vaccines. Cancer is considered to be primarily a disease of the older age and yet many children suffer from or succumb to cancers such as leukemias, glioblastomas, neuroblastomas and sarcomas. Standard therapy, even when curative, is accompanied by serious side effects, including secondary tumors later in life. Due to the greater capacity of a young immune system to recover after cancer treatment, therapeutic vaccines are expected to have a better chance to elicit protective immunity and prevent cancer recurrence in children. In this review, we discuss the current efforts at designing and testing cancer vaccines in children with the focus on specific tumor antigens expressed by pediatric cancers.