If you have someone around you who has cancer, you may have heard of a treatment called immunotherapy. In fact, this method uses the components of the patient’s immune system to help fight cancer.
Ways to stimulate the immune system to fight cancer
It stimulates the patient’s immune system to fight cancer in two ways:
The immune system is intelligently stimulated to selectively attack cancer cells
A number of proteins that are the productions of immune system activity enter the patient’s body to fight cancer cells.
Biological therapy or biotherapy are new methods of immunotherapy.
What does the immune system do?
A set of organs and their cells, together with the materials made by these cells, are responsible for protecting the health of all parts of the body against any external and internal harmful factors, which are collectively called the immune system.
This highly specialized and complex system is responsible for fighting against infectious agents such as viruses, bacteria, fungi and environmental toxins and preventing the body’s cells from becoming cancerous.
The function of this system is such that any unknown protein in the body, including components of viruses, bacteria or substances made by cancerous tumors, is identified and destroyed by this immune system as an unknown agent.
Immune system and cancer
The immune system has a harder time fighting cancer cells because not every cancer cell is necessarily considered unknown by our immune system and sometimes the function of the immune system is not enough to fight and destroy cancer cells.
Sometimes some cancerous tumors make substances that prevent the immune system from responding. To improve the immune system’s ability to recognize and fight cancerous tumors and boost or improve its function, doctors and researchers use methods called immunotherapy.
Artificial cancer immunotherapy
A series of proteins (antibodies) that are naturally made in our body by the immune system under certain defense conditions are now man-made and purified in advanced laboratories. These proteins are called monoclonal antibodies, which have different types of characteristics. The do their job selectively and specifically on a specific part of the cancer cell structure and in a unique location.
In short, with immunotherapy, specific parts of the human immune system are strengthened and used to fight diseases, including cancer.
Immunotherapy works in the following ways:
Immunotherapy stimulates the immune system to fight diseases, including cancer cells, both more powerfully and intelligently.
Nowadays, immune system products made in equipped laboratories have been injected into the patient’s body and have been very effective in fighting cancer cells and diseases.
Immunotherapy has become very important in recent decades and is rapidly expanding.
Types of immunotherapy in the treatment of cancer
These drugs prevent the immune system from stopping, and as a result, the patient’s immune system becomes stronger and faster in its defense.
Important safety system checkpoints are:
PD1 is a protein that is located on T lymphocytes and is an (off switch) for the immune system that prevents immune cells from fighting harmful agents. In fact
PD1 is a protein that is found on the surface of healthy cells. And there are some cancer cells (PDL One) attached
And this binding to T lymphocytes sends the message that it is moving away from the cells and releasing them. In this way, the cancer cells escape from the immune system.
Another protein on the surface of T lymphocytes that prevents the immune system from detecting cancer cells is called CTLA4, which is an off-switch defense system.
Useful inhibitors for cancer
Today, monoclonal antibodies are made to bind directly to the PD1 or PDL1 and block their activity so that the immune system can recognize and kill cancer cells.
Some of these drugs include:
- pembrolizumab (keytruda)
- Nemolizumab (Opdivo)
- Cemiplimab (Libya)
- atezolizumab (tecentriq)
- Durvalumab (emphysema
Inhibitors (CTLA 4):
Side effects of cancer inhibitors
Side effects of this class of drugs (checkpoint inhibitors):
- Skin rash
- Hormonal changes
Usually, the drug is stopped for a while only if the side effects are severe so that the body has a chance to recover.
Chimeric antigen receptors CART cell therapy
In this method a certain amount of blood is taken from a patient and its T lymphocytes are isolated then in a sterile laboratory environment specific man-made receptors are added to the surface of these T lymphocytes to attach much better and more to cancer cells. In this way T lymphocytes are equipped and strengthened to identify and bind to cancer cells.
These T-lymphocytes equipped with the patient’s blood, then return and begin to identify and fight cancer cells. This method is called gene therapy or immunodeficiency cell therapy.
The mechanism of action of gene therapy
The cells of each type of cancer have their own antigen, so T lymphocytes need a special receptor to bind to any type of cell. Receptors on T lymphocytes Surface bind to antigens on the surface of the cancer cell and the immune system targets that cell for destruction. Without this binding, defense is not possible
In the method (CART cell therapy), different receptors for each man-made cancer are attached to the surface of the T cells and they are equipped and prepared to connect to that type, especially the cancer cell.
The patient lies in bed and two IV lines are taken from him. During the process of leukophoresis, white blood cells are removed and the rest of the blood returns to the patient’s body through another IV line.
Isolated white blood cells go to the laboratory and T lymphocytes are removed from it.
Now, in the special sections of the specialized chimeric laboratory, a specific receptor antigen suitable for the patient’s cancer is added to the surface of T cells. These new T cells are called (CAR T cells).
When (usually after a few weeks) a sufficient amount of CRT is available, the patient is called in to receive their infusion.
So far, the FDA has approved this method for a number of types of lymphoma and some types of leukemia.
Among the approved types, the following products can be mentioned:
- Leukocell tease (Chimeria)
- Acisabetagen Cellulose (Yaskarta)
- Brexucabtagene autoleucel (Tecartus)
CAR T cell therapy side effects
The side effects of this method are:
- Severe fever
- Dangerous hypotension
- Which are collectively called (cytokine release syndrome)
- Neurotoxicity (toxicity to nerve cells) that can cause:
- Cerebral edema
- Decreased consciousness
Antibodies are the product of the activity of the immune system in the path of destroying the pathogen, that is, to eliminate any antigen (a substance that is present on every cancer cell or any foreign agent), our body makes a special type of antibody that only destroys the particular type of antibody.
Today, in specialized laboratories, these types of antibodies are made by researchers and are used in treatment depending on the type of disease or cancer. These drugs contain substances that are made specifically to fight the antigen on the cells of that cancer. (Target therapy).
Types of monoclonal antibodies
Naked monoclonal antibodies:
These are antibodies to which no drugs or radioactive substances have been attached. These are the most common types used to treat cancer.
Almetozumab (Compat) in the treatment of CLL
Trastuzumab (Herceptin) in the treatment of breast cancer (herto-positive) and gastric cancer
Monoclonal conjugated antibodies:
They attach to chemotherapy drugs or radioactive particles. These substances circulate in the body to reach their target cell and begin to work there.
Ibritumomab (Zevalin): It is attached to a radioactive particle and from the composition:
Rituximab, a pure naked monoclonal antibody, is made with a radioactive substance.
These treatments are called radioimmunotherapy.
Brentoximab (Adsertis): This drug consists of binding a monoclonal antibody to a drug (MMA).
Ado-trastuzumab emtansine (Cadillac): Again, it is a combination of a naked antibody monoclonal with a chemotherapy drug that it is used in the treatment of Herto positive breast cancers and some stomach cancers.
Monoclonal biospecific antibodies:
These compounds are composed of two different monoclonal antibodies, meaning that they can act specifically against two different antigens.
Blinatumomab (Blincyto):Used to treat a variety of leukemias and lymphomas.
monoclonal antibodies side effects
Some of the side effects of monoclonal antibodies are:
- Fever, chills
- Nausea / vomiting
- Low blood pressure
- Skin rashes
Some types of monoclonal antibodies have side effects that are caused by their target cell type:
Which has a specific effect on the antigen that causes the growth of vascular tumors
Side effects of this drug include:
- High blood pressure
- Renal injury
- Wound healing problems
It targets an antigen called protein (EGFR), which, in addition to the surface of cancer cells, is normally present on healthy skin cells, so it is associated with very severe skin rashes.
Vaccines stimulate the immune system to produce and defend antibodies by inserting fragments of the pathogen.
There are vaccines that can prevent cancer:
The human papillomavirus vaccine activates the immune system against several types of the carcinogenic virus. Vaccination in young children and adults protects them against cervical cancer and five HPV-related cancers.
A vaccine that is given against the hepatitis B virus to prevent liver cancer.
Vaccines used to treat cancer
These vaccines are made from pieces of cancer cells or their antigens, and when they enter a patient’s body, they stimulate his or her immune system to fight the cancer.
This vaccine is used to treat advanced prostate cancer.
Side effects of the vaccine include fever, fatigue, joint pain, high blood pressure, and respiratory problems.
It is a vaccine used to treat skin melanoma.
The vaccine is made from a type made from a type of herpes virus in the laboratory
which can stimulate and strengthen the human immune system to defend against melanoma.
Cytokines are substances (small proteins) that play a very important role in the growth and stimulation of our immune system. In other words, when cytokines are released in our body, signals for further activation are sent to the entire immune system. Interleukins, interferons, tumor necrosis factors, and growth factors are very important cytokines or chemokines.
Today, some cytokines are made in laboratories and used to treat a wide range of diseases.
They have alpha, beta and gamma types and interferon alpha is the only interferon that is used in the treatment of cancers and is used in the treatment of the following diseases:
- Leukemia hair cell shape
- Chronic myelogenic leukemia
- non Hodgkin follicular lymphoma
- Cancer kidney
- Kaposi sarcoma
Some types of interferons are used in autoimmune diseases such as MS.
- Interleukin II: Today it is made in laboratories and is used for kidney cancer and melanoma.
- Interleukin II accelerates the growth and division of immune system cells.
- Talidomide (Multiple Myeloma)
This bacterium does not cause serious disease for humans, but it strongly stimulates the immune system.
It is used today for the early stages of bladder cancer.
This drug is available in the market in the form of topical cream. This drug stimulates the local reaction of the immune system in the applied position and has very early stages of skin cancers, especially if used.
It is also used in vitiligo which is an autoimmune skin disease. Today special immunotherapy methods are used to treat and control autoimmune diseases such as MS, Graves and systemic lupus. The US Food and Drug Administration has approved immunotherapy for a variety of non-Hodgkin’s and Hodgkin’s lymphomas in children and adults.
Immunotherapy is one of the most promising treatments for lung cancer