Your immune system is your army against pathogens and invaders.
Immunotherapy def. : Is a biological thereby to fight cancer by boosting your immune system to recognize cancer and inhibit their growth or could make your immune system destroy cancer cells
NOTE: biological thereby is a type of treatment that uses living organisms to treat cancer
So how your immune system recognize abnormal cells (cancer)??
You must know that your cells is under surveillance of your immune system. when your immune system find abnormal cells, they start attacking them.
But, cancer is a very dangerous illness which could get around your immune systems’ natural defenses allowing cancer cells continue growing.
How immunotherapy work against cancer?
There are different types of immune therapy and each one work in different way
put it in your mind the goal is make your immune system stronger enough to destroy cancer or ban cancer from spreading to another organs in the body so we could combine it with other treatments of cancer
types of immunotherapy
1\ monoclonal antibodies and Tumor agnostic treatments such as check inhibitor
2\oncolytic virus therapy
3\oncolytic virus therapy
monoclonal antibodies (MBAs)
*it represents antibodies that are made by identical immune cells which are all cloned by same parent cell.
*Many types of monoclonal antibodies are available to treat specific types of cancer and newer types are still in clinical trials.
so how they work?!
You know that antibodies IS A PROTEIN which produced by B_cells and sticks to with specific PROTEIN called Antigen.
They work by 3 mechanisms
the main types of cancer targeted by MBAs are COLON, BREAST, LYMPHOM CANCER
Monoclonal antibodies mechanisms against cancer
Inhibition of the factors and receptors that activates signal pathways used by cancer cells in Division and angiogenesis by antibody binding.
Antibody-dependent cellular cytotoxicity(ADCC) Which is composed of target monoclonal antibodies formed from either chimeric or full human antibody components that binds to a specific tumor associated antigens
complement dependent cytotoxicity (CDC) by complement activation
In ADCC mechanism, mAb first binds to antigens on the
surface of target cells such as tumor cells and then the Fc
receptors of immune cells such as macrophages and natural
killer (NK) cells recognize cell-bound mAbs. Cross-linking
of receptors cause releasing cytotoxic agents such as perforin and granzyme into a lytic synapse. Finally, tumor cells
die by apoptosis.
Whereas in CDC mechanism, mAb
binds to membrane-surface antigens on the target cell and
thus multiple pathways elicit a complement cascade, where
complement binds to the mAbs. Binding of complement
leads to the induction of a membrane attack complex and
activated complement system lyses the target cell.
What is a tumor-agnostic treatment?
A tumor-agnostic treatment is a drug treatment that is used to treat any kind of cancer, regardless of where in the body it started or the type of tissue from which it developed. This type of treatment can be used when the tumor has a very specific molecular alteration that is targeted by the drug or predicts that the drug is likely to work .Most cancer treatments are developed to treat a cancer that has developed in a specific organ or tissue, like breast cancer or lung cancer. A tumor-agnostic treatment treats any kind of cancer if the cancer has the specific molecular alteration targeted by the drug.
Cancer treatment vaccines, also called therapeutic vaccines, are a type of Immunotherapy. The vaccines work to boost the body’s natural defenses to fight a cancer. Doctors give treatment vaccines to people already diagnosed with cancer. The vaccines may:
Prevent the cancer from coming back
Destroy any cancer cells still in the body after other treatments have ended
Stop a tumor from growing or spreading
in 2010, the FDA approved sipuleucel-T (Provenge) for men with metastatic prostate cancer.
Note: Metastatic means the cancer has spread from where it began to other parts of the body.
First, white blood cells are removed from the person’s blood. White blood cells help the body fight infections and diseases.
Then the white blood cells are modified in a laboratory to recognize and target prostate cancer cells.
Next the modified cells are put back into the person through a vein. This is like a blood transfusion. The modified cells teach the immune system to find and destroy prostate cancer cells.
Cancer prevention vaccines:
Doctors give prevention vaccines to healthy people to keep certain cancers from developing.
Like vaccines for the chicken pox or the flu, they protect the body from viruses that can cause disease.
A person has to get the vaccine before the virus infects him or her. Otherwise, the vaccine will not work.
There are 2 types of cancer prevention vaccines approved by the U.S. Food and Drug Administration (FDA): HPV vaccine:
The vaccine protects against the human papillomavirus (HPV). If the virus is long-lasting, it can cause some types of cancer.
The FDA has approved HPV vaccines to prevent:
Cervical, vaginal, and vulvar cancer, Anal cancer, Genital warts.
HPV can also cause other cancers the FDA has not approved the vaccine for, such as oral cancer.
Hepatitis B vaccine. This vaccine prevents hepatitis B virus (HBV) infection. Long-lasting infection with HBV can cause liver cancer.
ADOPTIVE CELL THERABY
Types of adoptive cell therapy include chimeric antigen receptor T-cell (CAR T-cell) therapy and tumor-infiltrating lymphocyte (TIL) therapy. Adoptive cell therapy that uses T cells from a donor is being studied in the treatment of some types of cancer and some infections. Also called adoptive cell transfer, cellular adoptive immunotherapy, and T-cell transfer therapy
Oncolytic Virus Therapy: Using Tumor-Targeting Viruses to Treat Cancer
Since the late 1800s, doctors have observed that some patients with cancer go into remission, if only temporarily, after a viral infection.
Today, several dozen viruses—and a few strains of bacteria—are being studied as potential cancer treatments, according to research presented at an NCI-sponsored conference on using microbes as cancer therapies in 2017.
“Oncolytic virus therapy is of growing interest to researchers for one reason: It’s working,” said Juan Fueyo, M.D., of the University of Texas MD Anderson Cancer Center, who co-developed a type of oncolytic virus being tested in patients with brain tumors.
By Mennat Allah Ahmed mohamed