Vaccines already exist to prevent some cancers, including those caused by viruses like HPV and Hepatitis B. The trial begins next year and will test the vaccine in people with Lynch syndrome who have inherited mutations that raise their risk of colon and breast cancer. The vaccine comprises bits of DNA from tumor cells or short pieces of protein (peptides). When these antigens are injected into the body, immune cells produce antibodies that attack the cancer cells.
Vaccines are a Form of Immunotherapy
A vaccine is a suspension of attenuated or inactivated organisms or purified products from them that stimulate the body’s immune response. These include antibodies, lymphocytes or RNA molecules used to prevent or treat diseases. Cancer immune prevention vaccine can also minimize the risk of developing the disease. Human papillomavirus (HPV), for example, can cause cervical cancer, and hepatitis B (HBV) can cause liver cancer. Vaccines against these viruses can prevent them from developing into cancer. Some vaccines target tumor antigens found on cells in many patients with the same type of cancer. This approach, known as neoantigen vaccines, may enable immune responses that target only the cancer cells rather than healthy cells in the patient. These newer vaccines are still experimental and need to be tested in people with a genetic, environmental or lifestyle risk for cancer. They are usually given as part of combination therapy. For example, the HER2-pulsed dendritic cell vaccine sifu-T effectively treated DCIS (pre-cancer) in women with mutations in BRCA1 and BRCA2. However, this combination trial did not evaluate the vaccine alone.
They Stimulate the Immune System to Fight Cancer
Researchers are now beginning to study vaccines that can treat existing cancers. They aim to stimulate the immune system and prevent it from becoming insensitive so that it can recognize and attack cancer cells. This is known as therapeutic vaccination. These vaccines can be made in several ways. One approach uses autologous tumor cells, taken from a patient’s cancer cells and then used as the vaccine. This allows for a personalized treatment. Another method uses mRNA to target cancer-associated antigens unique to each patient. Vaccines that use dendritic cells are also being developed. These are cells that help the immune system recognize and attack abnormal cells. Scientists can make them grow alongside cancer cells in the lab and then use them as a vaccine. They can also change viruses in the lab and use them as a carrier to deliver cancer antigens into your body.
They are Safe
The Food and Drug Administration (FDA) reviews all vaccines to ensure they are safe. Most vaccines contain small amounts of weak or dead germs that don’t cause disease. They can still spark a strong immune response without the serious symptoms of getting the disease. This helps your body learn to fight the germ and remember it so it can quickly attack it again if it ever invades. Therapeutic cancer vaccines expose your immune system to molecules, or antigens, associated with a specific type of cancer. These antigens can help your body recognize and kill the cancer cells. They can also help you avoid surgery, delay or shrink tumors, and prevent them from returning after treatment.
They are Effective
Vaccines operate by ‘tricking’ the immune system into producing antibodies without exposing patients to the disease. Vaccines contain antigens, which are dead or weakened viruses or bacteria. When the “vaccine-induced antibodies reach the real germ, they can attack it and prevent infection. Moreover, vaccines can also train the immune system ‘to remember the embryo to fight it again. This memory helps to reduce the risk of disease for a long time. Vaccines against cancer-causing viruses, such as human papillomavirus for cervical cancer and hepatitis B virus for liver cancer, effectively prevent the initial infection and thus significantly reduce the risk of associated cancers. This approach has shown great promise and may be a powerful tool for fighting tumors, especially those with many immune-evasion mechanisms. Some vaccines may be combined with other therapies to enhance their effectiveness, such as oncolytic viruses that infect and destroy cancer cells and checkpoint inhibitors, which block the pathways that suppress self-reactive immune cells.
