What are Cancer Vaccines?
Vaccines aid the body’s defenses against illness. They can make the immune system more effective in finding and eliminating pathogens and cancerous cells. Vaccinations are given to you at various times during your life to protect you from certain illnesses. Cancer vaccinations have also been developed. Cancer vaccinations are available to both prevent and treat the disease.
Can cancer be prevented with vaccines?
Vaccines exist to protect healthy people from contracting some viral malignancies. Vaccines protect the body from infections like chickenpox and flu. This vaccination is only effective if given to a person before they get infected.
U.S. Food and Drug Administration (FDA) has authorized two types of vaccinations to prevent cancer:
Vaccine against the human papillomavirus. Human papillomavirus immunity is provided by the vaccination (HPV). This virus can cause some forms of cancer if it persists in the body for an extended time. HPV vaccinations have been given the go-ahead from the FDA to prevent:
- Anal cancer
- Genital warts
- Cervical, vaginal, and vulvar cancers
Other malignancies caused by HPV, such as oral cancer, are not covered by the FDA’s approval of the vaccine.
Vaccination against hepatitis B – The hepatitis B vaccination helps to protect against the infection (HBV). When infected, this virus has been linked to liver cancer.
Are there vaccines that treat cancer?
Treatment vaccines sometimes referred to as therapeutic vaccines, are vaccinations used to treat patients who already have cancer. Immunotherapy, the medical term for what these vaccinations are, is a form of cancer treatment. They act to improve the body’s ability to fight cancer by boosting the immune system.
People with cancer can receive treatment vaccinations from their doctors. There are several therapeutic vaccines available, each with a unique mechanism of action. They have the potential to:
- Prevent the cancer from returning
- Destroy any cancer cells that remain in the body after therapy has ended
- Stop the growth or spread of a tumor
What is the mechanism of action of cancer vaccines?
Immune systems recognize antigens on the surface of cells as foreign invaders and attack them. Antigens are attacked by the immune system, which usually eliminates them. As a result, the immune system has a “memory” of the antigens it encountered and may use that to its advantage in future battles.
Vaccines for cancer treatment increase the ability of the immune system to identify and eliminate foreign antigens in the body. Certain cancer-specific antigens are found on the surfaces of cancer cells, but these molecules are absent from healthy cells. These compounds function as antigens when given to a person via a vaccination. When these chemicals are found on cancer cells, the immune system is notified to go out and eliminate those cells.
Cancer vaccinations can be tailored to the patient’s specific needs. This implies that they were designed for a single user. This vaccine is made from tumor samples that are removed after surgery and are administered to the patient.
Other cancer vaccines do not target specific antigens but rather general antigens present in all cancer patients. These vaccinations are administered to patients whose malignancies have antigens on the surface that match the antigens in the vaccine.
In most cases, cancer vaccinations are only available as part of clinical trials, which are research studies in which participants voluntarily participate.
To treat men with metastatic prostate cancer, the FDA authorized sipuleucel-T (Provenge) in 2010. Sipuleucel-T is customized for each patient in a step-by-step process:
- The person’s blood is processed to separate the white blood cells. When it comes to fighting infection and disease, white blood cells play a critical role in the body. Prostate cancer cells are targeted using white blood cells that have been genetically modified in the lab. The doctor will next use a vein to reintroduce the patient’s own cells.
- Similar to a blood transfusion, this is a life-saving procedure. The immune system needs the help of these engineered cells to detect and eliminate prostate cancer cells.
- Another vaccination makes use of an intramuscular injection of Bacillus Calmette-Guérin (BCG), a weakened strain of bacterium. Doctors use this weaker version of the bacteria to stimulate the immune system to treat bladder cancer in its early stages.
What are the drawbacks to taking vaccinations for medical conditions?
Making effective therapeutic vaccines is difficult:
- Due to the immune system suppression caused by cancer cells, cancer is able to start and develop. Scientists include adjuvants, a chemical that boosts the immune response to an antigen to address this issue.
- Cancerous cells originate from healthy cells in the body. As a result, the immune system may not see the cancer cells as a threat.
- Vaccination doesn’t work well on larger tumors or more advanced cancers. One of the reasons why a cancer vaccination is commonly prescribed in conjunction with other treatments.
- People with weakened immune systems, including the ill and elderly. Their immune systems may be weakened as a result of the vaccine they received. As a result, vaccination efficacy is constrained. In addition, several cancer therapies might impair immunity. A vaccine’s ability to work is hampered because of this.
Researchers believe that cancer therapy vaccines may be more effective for early-stage cancers or tumors that are smaller for these reasons.
Vaccines and clinical trials
In order to understand more about cancer-preventive vaccinations and cancer therapy vaccines, clinical trials are critical. Many types of cancer vaccines are now being tested by researchers, including:
Bladder cancer – Scientists are now testing vaccines derived from viruses mutated to include the HER2 antigen. Some bladder cancer tumors have antigens or chemicals that express themselves on their surfaces. Cancer cells can be taught to self-destruct by viruses that assist the immune system do its job. In addition, scientists want to determine if normal bladder cancer therapy or standard bladder cancer vaccination treatment is more effective.
Brain tumors – Research is being conducted to see if therapy vaccines targeting specific molecules on brain tumor cell surfaces would be effective. Some studies are concerned about brain cancer that has recently been discovered. Cancer that has returned or recurred is the focus of some. Children and teenagers are often included in research projects.
Breast cancer – Vaccines for breast cancer treatment are being tested in several studies, either on their own or in conjunction with other therapies. Another group of scientists is attempting to get vaccinations to clinical trials that will protect against breast cancer.
Cervical cancer– The FDA has authorized HPV vaccinations to help prevent cervical cancer, as previously stated. Vaccine development for cervical cancer is still ongoing.
Colorectal cancer – Treatment vaccines are being developed by scientists instructing the body’s immune system to attack cells carrying antigens associated with colorectal cancer. Carcinoembryonic antigen (CEA), MUC1, guanylyl cyclase C, and NY-ESO-1 are examples of these antigens.
Kidney cancer – Cancer vaccines are being investigated by scientists to treat and prevent kidney cancer. They’re also experimenting with vaccinations to keep kidney cancer from returning if detected in its later stages.
Leukemia – Treatment vaccines for several forms of leukemia, such as AML and CLL, are being investigated in studies (CLL). For instance, a bone marrow/stem cell transplant is designed to make other therapies function better.
Lung cancer – Clinical studies on vaccinations to treat lung cancer aim to target specific antigens.
Melanoma – In conjunction with other therapies, scientists explore a wide range of melanoma vaccinations. Vaccine antigens and destroyed melanoma cells instruct the immune system to attack and kill any remaining melanoma cells in the body.
Myeloma – People in the last stages of remission from multiple myeloma are participating in several clinical trials to determine the effectiveness of vaccinations. Doctors are unable to detect cancer in the body, and there are no signs or symptoms to indicate this. Vaccines are also being tested on patients with smoldering myeloma or who need an autologous bone marrow/stem cell transplant by researchers.
Pancreatic cancer – Many therapeutic vaccines are being developed by scientists to improve the immune system’s response to pancreatic cancer cells, according to the latest research. The vaccination can be used alone or in conjunction with other therapies.
Prostate cancer – As previously stated, sipuleucel-T is a vaccination that doctors may use to treat patients with metastatic prostate cancer. Now, trials are being conducted to see whether the vaccination might benefit those diagnosed with prostate cancer at an earlier stage.