A cancer diagnosis is one of the hardest things patients have to face. No matter the details, side effects, and symptoms of the disease, patients have to tackle a variety of obstacles when figuring out what treatment options are available to them.
For many years, treatment options for cancer included little aside from chemotherapy and radiation. Though these are a great option for a variety of different cancers, immunotherapy is proving to be an additional option in many situations. This method may give patients a way to fight cancer without the risk of radiation or chemicals killing healthy cells.
What Is Immunotherapy?
When a person has cancer, their body has been going through a process called tumorigenesis, the process of abnormal cell reproduction and growth. This cell growth is commonly called a tumor. The tumorigenesis process gives cells malignant properties and enables the tumor cells to learn how to bypass the body’s immune system, rendering the body incapable of fighting the spread of cancer naturally.
Radiation and chemotherapy treatments attack the tumor when the immune system cannot. However, it is difficult for these treatments to target cancerous cells, and they often kill healthy cells as well. Instead, immunotherapy uses the patient’s own immune system to attack a growing tumor.
How Does Immunotherapy Work?
Growing tumors can bypass the body’s immune system and multiply. If doctors are able to discover how the patient’s tumor is circumventing the immune system, they can begin to identify ways to get the immune system to recognize cancerous cells.
Currently, immunotherapy is not always effective in the long term. However, that may be changing due to some new research out of Tokyo Medical and Dental University and Harvard Medical School.
The PD-L1 Protein
Researchers have recently discovered that the PD-L1 immune checkpoint protein is central in increasing the efficacy of immunotherapies. They have found that blocking this specific protein checkpoint may inhibit the tumor from growing. Once the protein source is blocked, the tumor has a more difficult time growing larger, and the body can better fight the cancer.
The efficacy of this method depends on the role of the PD-L1 protein in the tumor itself. The more central PD-L1 protein is in the tumor’s growth process, the more likely the patient will respond to PD-L1 blockade as part of their immunotherapy treatment. If PD-L1 is significantly expressed in the tumor, the patient may similarly experience positive benefits from immunotherapy.
The Research
Researchers came to this discovery by way of several different molecular and biochemical research attempts. They assessed localization, function, interactions, and protein stability after acetylation of the PD-L1 protein.
Researchers at both Tokyo Medical and Dental University and Harvard Medical School found that introducing the enzyme p300 into the protein’s acetyl function group produces a specific cytoplasm residue (Lys263). At this residue, PD-L1 seems to have a role in regulating the tumor’s immune environment and making it more sensitive to immunotherapy, potentially preventing cancer’s spread.
The Future Of Cancer Treatment
This discovery could lead to a wider, more effective use of immunotherapy in cancer treatment. With the increased rate of efficacy of immunotherapy treatment, experts expect cancer survival rates to grow.
Sources:
https://www.eurekalert.org/pub_releases/2020-09/tmad-ite091820.php (from Sept 2020)
