Immunotherapy

What does your immune system do?

From fighting a common cold to fighting infections, the immune system helps to protect you from disease and infection. If the immune system tracks bacteria or viruses, and works to attack and eradicate the foreign substance. Occasionally, the immune system does not recognize cancer cells as a foreign substance, and therefore does not attack the growing cells.

Researches were exploring the possibility that the immune system could be harnessed to create a more targeted treatment for cancer, and discovered there are multiple ways that the immune system can be “improved” on it’s fight against cancer.

What is cancer immunotherapy?

Immunotherapy harnesses the body’s immune system to better fight diseases, like cancer. Man made modifications to the immune system can help your body to be better able to fight, slow down or stop growth of cancer cells. The range of immunotherapy treatments have grown over the years, and more are being studded, from general boosts to the immune system to specific targeting of cancer cells.

As we are learning more about specific type of cancers, we are able to better create immunotherapy treatments for them.

Types of cancer immunotherapy including Targeted Therapy

Monoclonal antibodies / Targeted Therapy

1When the body’s immune system detects viruses, bacteria or other harmful substances, it produces antibodies. Since some cancers can go undetected by the immune system as a harmful substance, we’ve been able to create antibodies in a laboratory and introduce it to the body. The laboratory made antibodies are created to only attack the cancer cells and enable the body to fight the cancer cells, either killing them or slowing growth. Scientists have even been able to use this function of antibodies to diagnose prostate, colon and gynecologic cancers by leaving a radioactive trace that can show up on imaging, so a pathologist will know where to biopsy on the organ.

Special antibodies that are fused with radioactive molecules can carry radiation treatment directly to the cancer cells and do not radiate the healthy cells. Breast cancer and Hodgkin and non-Hodgkin lymphoma have a immunotherapy cancer treatment that uses these antibodies that are created in a lab to carry cancer drugs directly to the cancer cell, and attaches to it. Once again, this technology allows only the cancer cells to be damaged, and leave the healthy cells alone. This is called a targeted therapy, which simply means that the antibodies are created to only attach to specific genes or proteins. Further development of these monoclonal antibodies are ongoing in clinical trials.

Check-point Inhibitors

This therapy is creating exciting advances for many different types of cancer, because unlike other immunotherapies, it does not target specific proteins that vary from cancer to cancer, but instead target proteins of the immune system. Specifically it harnesses the detection power of T cells, which essentially every person has. One of the responsibilities of T cells is to find abnormal cells within the body, but as previously mentioned, cancer cells can be deceptive and cloak themselves with normal proteins that trick the T cells into thinking the cancer cell is actually a harmless and healthy cell. Check-point inhibitors block this pathway, therefore the cancer cells loose their ability to ‘blind’ T cells against them.

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In this diagram you can see the tumor is covering itself in antigens (protein) that then tricks the T cell into thinking the tumor cell is a healthy cell.

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In this diagram you can see that even though the tumor is still covered with antigen, the T Cell stays active because of the check-point inhibitors and calls for the immune system to destroy the cells.

Alternative Immunotherapy

There has also been development of cells created in a laboratory that are not “targeted therapy” but helps to give a boost to the immune system. The two main types of non-targeted immunotherapies are Interferons and Interleukins. Interferons join along side the immune system to slow the growth. Interleukins help to boost the immune system by telling the body to create more cancer killing cells than it would normally. This drug is often used to treat kidney and skin cancer. However this treatment is used limitedly due to side -effects and reduced efficiency.

Cancer vaccines

Vaccines are common and used to treat many diseases such as small pox, polio and the flu. Vaccines work by exposing the immune system to a small dose of the disease so that it can recognize it, and destroy those cells. Cancer vaccines have been developed for both prevention and treatment of some cancers. A prevention vaccine is given to a person to prevent a specific type of cancer, such as liver or cervical cancer, because there are indications of which strands of disease may raise risk factors for that cancer type. Such as HPV and Hepatitis B.

Vaccines as a treatment is currently only an option for prostate cancer, though others are undergoing clinical trials. This vaccine is given to someone who has cancer, and is a way to help train the bodies immune system to recognize the cancerous cells as a hazardous substance and destroy it. The vaccine may prevent recurrence, eliminate any remaining cancer missed by the primary form of treatment, or prevent the disease from spreading.

Immunotherapy treatment in San Francisco Bay Area is available. To learn if immunotherapy is the right choice for you or a loved one, contact us to schedule an appointment.