Researchers report that CBD inhaled reduces the size and lethality of the brain tumor glioblastoma, which is extremely aggressive, in an animal model. This is due to the reduction of its essential support system.
After only seven days of treatment, Dr. Babak Baban, immunologist at Augusta University and associate dean for Research at the Dental College of Georgia, stated that there was a significant reduction of the tumor’s size.
Researchers at DCG, the Medical College of Georgia, claim that the inhaler approach to cannabis delivery has not only ensured that the compound found in cannabis reached brains, but that patients could eventually use the delivery method, much like inhalers for asthma.
The first study to use CBD as a treatment for glioblastoma in an animal model was reported in the journal. Research on Cannabis and Cannabinoid.
They created an orthotopic model of glioblastoma using modified human glioblastoma cells. This was to give the most realistic representation possible for this deadly and common malignant brain tumor. The mice developed an aggressive tumor in their brains by day 8. They began to inhale CBD daily or a placebo every day for seven days. The mice then examined a second image of the tumor, and the tumor tissue.
Although the approach can be applied to humans, they are focusing primarily on the biological response of the cancer to CBD. Dr. Martin Rutkowski is a MCG neurosurgeon who has experience operating on patients who present after a seizure, sudden loss of consciousness or with slower onset neurological deficits such as a weak arm or vision, or those with cognitive problems.
It’s one of the most deadly types of cancer. The neurosurgeon and coauthor of the study says that we are in dire need of more treatments and research. He says, “What we have at the moment is not working very well.”
Rutkowski states that family members will bring in patients to tell them that they are having trouble thinking, that their memory is faulty, or that they lost their job because they are not doing the same thing they’ve been doing for 30+ years.
Today’s treatment includes surgery followed by chemotherapy and radiation therapy. Rutkowski said that although surgery does not provide a cure, it does provide an important first step in optimizing quality of life. She also noted that there is a direct relationship between the size of the tumor and the survival rate.
They discovered that CBD was able to alter the tumor’s ecosystem or supportive tumor microenvironment. It also restored levels of inflammation that target and not protect the glioblastoma. This could make CBD an effective, safe, and novel adjunct therapy.
Baban, the corresponding author, says that “it is about immune balance.” Inflammation increases in response to a frontline assault on a cancerous tumor. This is a normal response. Our immune system is constantly attacking precancerous or cancerous cells. However, once a tumor has established itself, it switches to producing chronic inflammation that eventually protects it from the immune systems.
The tumor microenvironment is the environment created by cancer cells. It includes immune cells, blood vessels, growth factors, and other growth factors that enable more blood vessel development. This is key to tumor growth, survival, and allowing it to thrive where it begins and spread.
A glioblastoma is characterized by an increase in activity of natural immune checkspoints. These checkpoints help prevent overzealous immune responses that could cause harm to the body. In this instance, damping down is about protecting the tumor. There is also a very low number of cytotoxic cells, which are adept at attacking tumors and other invaders.
CBD was found to be able to improve the immune system against the tumor. It also reduced the tumor’s coopting glial cells, a type of brain cell that normally protects neurons and produces inflammation to fight invaders. The tumor has now become a major component, the glioblastoma-associated macrophage. This helps to support and protect it.
It also suppressed P–selectin, a protein that is often involved in important functions, such as injury repair. One of the things it recruits for help is platelets. P-selectin is a key component of cancer treatment. It helps tumors spread and resist treatment. There is evidence that P-selectin acts as an immune checkpoint, just like many other microenvironments.
Apelin, a ubiquitous enzyme that is made by many cell types, is usually found at low levels in the brain. The researchers found that glioblastoma has an increased expression of apelin. This enzyme supports blood vessel growth and promotes the development of cancer stem cells. Evidence also suggests that apelin acts as an immune checkpoint in tumor microenvironment. Others have shown that CBD inhibits the growth of deadly brain tumors.
CBD also suppresses IL-8 which macrophages normally release in order to promote inflammation and aid in injury repair. It recruits other immune cell during this process. However, glioblastoma also secretes IL-8 in order to promote cell migration. This has been confirmed to be the case in many cancers including glioblastoma. These tumors grow quickly and are capable of growing blood vessels which, in turn, support their growth. Drugs that target this skill have been proven to be beneficial.
CBD reduces other immune checkpoints such as the enzyme indoleamine 2,3-dioxygenase (IDO), which is another localized blockade of the immune response that tumors have been known to use.
CBD also helped improve the mix by increasing expressions of certain good things. CD103, which is thought to help the body recognize cancer, is associated with a better chance of surviving it, as well CD8, which is a sugar-coated protein, that aids in the immune response. CBD has been shown to increase levels of both, by suppressing immune checkpoints.
Baban states, “It is a puzzle.” He states that CBD is a smart regulator. It can adjust according to its environment. This includes turning apelin down for glioblastoma, and up for COVID-damaged lung tissue. DCG and MCG investigators last year reported that CBD actually raises levels of apelin. This is consistent with their findings that CBD reduces inflammation and contributes to the “cytokine hurricane” that has decimated the lungs of patients.
Baban says, “Right now, we are excited that it shrinks,” about the cannabinoid’s impact on glioblastoma. Rutkowski and Baban note that inhaled CBD has positive results without needing to be used in conjunction with surgery. They expect that CBD will eventually be used for these patients as an adjunct to other therapies.
Next steps include determining how long the positive effects last and further investigating the impact on cancer stem cell growth. They also want to evaluate CBD’s effect on the high recurrence rate of glioblastoma. Baban says they have more evidence to support their hope: In an earlier study, they incubated tumor cells in CBD before implanting them. Baban says that no tumors were observed.
Rutkowski states that the latest breakthrough in glioblastoma treatment was made more than 15 years ago with the addition to radiation of chemotherapy drug temozolamide. This increased survival by about one and a half months.
Baban and his colleagues decided to explore the possibility of CBD being able to control inflammation. They also have experience in researching other conditions, such as Alzheimer’s. Other researchers are also looking at CBD with THC. However, CBD is an interactive compound that interacts with other active compounds in cannabis like THC. The DCG and MCG researchers believe it would be more efficient when used alone.