Over the course of the 20th century, vaccines have become the most effective tool for preventing infectious diseases and allergies. They are used to prevent two of the most common cancers of infectious origin in humans: liver cancer and uterine cancer. Other cancers are not of infectious origin, but therapeutic vaccines are currently being studied in oncology to treat cancers that have already occurred. These vaccines are possible because cancer cells produce abnormal proteins which, under normal conditions, trigger an immune response that eliminates these cells.
Treating cancer by stimulating the immune system is not a new idea. Very advanced cancers that regressed spontaneously have been known since ancient times. At the beginning of the 20th century, William Cole, an American surgeon, injected bacterial extracts into connective tissue cancer tumors (sarcoma), triggering a non-specific inflammatory reaction in the tumor cells with very significant hyperthermia, and achieving results largely comparable to those obtained today with heavy chemotherapy. More recently, cancers of the bladder epithelium have been washed with a solution containing inactivated bacillus Koch (BCG) to trigger a cellular immune response against the cancer cells.
Today, many techniques exist to activate the immune system, many of them involving tissue engineering techniques. We will focus on classical vaccine techniques, namely the injection of one or more proteins or glycoproteins specific to the agent to be eliminated, accompanied by an adjuvant agent that amplifies the immune response against the preceding compounds. In this article, we describe the contribution of inorganic vaccine adjuvants to cancer immunotherapy.