Cannabis has a long history as a cancer treatment. In an archeological investigation, cannabis was found on the body of a 2,500-year-old Siberian woman. After further investigation, researchers suggestedthat this woman may have been using cannabis to ease symptoms of breast cancer. Today, many cancer patients still gravitate toward the herb. But, while breast cancer is one thing, is cannabis effective against leukemia? Here’s what the evidence suggests.
What is Leukemia?
Leukemia is a cancer of the bone marrow and blood cells. The disease affects white blood cells, causing them to proliferate and crowd out red blood cells. Red blood cells are vital for delivering oxygen from the lungs to the rest of the body. White blood cells are manufactured in bone marrow and are a part of the immune system.
Leukemia affects the cells that eventually differentiate into different types of white blood cells.
There are two main classes of white blood cells, and both of them can develop cancer. One type, called a lymphocyte, is responsible for making antibodies and defending the body against infection and irregularities like tumors. Myeloid stem cells provide the building blocks for several different kinds of blood cells, some of which respond to bodily distress signals and then engulf harmful pathogens.
Several major problems can arise with leukemia. For one, high levels of white blood cells mean that the body lacks vital oxygen-carrying red blood cells. This can cause anemia, which contributes to chronic fatigue, dizziness, and general feelings of illness. Easy bruising and bleeding also contribute to harm in leukemia patients.
Unlike healthy blood cells, cancerous white blood cells do not defend the body from infection. This means that patients with leukemia are particularly at risk of developing life-threatening illnesses. Fighting off the common cold or a fungal infection can be too taxing for a leukemia patient, making simple diseases life-threatening.
While often thought of as a children’s disease, leukemia most commonly affects adults. It is often classified as belonging to one of two primary categories, acute and chronic. Acute leukemia quickly becomes very serious. Chronic leukemia starts slower but can develop into a horrendous illness over time.
How is leukemia treated?
Standard cancer treatments are in no way gentle to the body. Leukemia is often treated with blood transfusions, chemotherapy, and radiation. As the American Cancer Society reports, 2 of 3 patients with acute myeloid leukemia go into remission. With follow-up chemotherapy after the initial round, half of all patients experience long-term cancer remission.
Unfortunately, chemotherapy can also come with some long-term side effects. Children who receive treatment for Hodgkin lymphoma or who received high doses of chemotherapy are more likely to develop heart problems later in life. Chemotherapy is also linked to:
- Lung problems
- High blood pressure
- Hormonal problems
- Hearing loss
While many patients survive leukemia, in many ways a cancer diagnosis is a life-long illness. Chemotherapy treatments affect both cancer cells and healthy cells, causing damage to the body. Surgeries are not only invasive, but they can lead to painful neuropathy and other problems throughout a patient’s life.
These side effects may not go away over time. Rather, they are often managed with additional medications and therapies. Overall, traditional cancer treatments can wreck havoc on the body, which is why there is such a pressing need to develop effective treatments that reduce harms. This precise reason is why there is so much interest in medical cannabis.
Is cannabis effective against leukemia?
A study published in May of 2017 found that two cannabis compounds cannabidiol (CBD) and tetrahydrocannabinol (THC) successfully kill leukemia cells on their own. However, the study also found that the cannabinoids work best when they are used after (not before) chemotherapy. The research was published in the International Journal of Oncology.
This study is a part of a quickly growing body of laboratory evidence that suggests that cannabis effectively kills cancer. For almost two decades, researchers have been studying the cancer-fighting properties of the cannabis plant in the laboratory.
Thus far, scientists have only experimented with cell cultures and animal models. Though, the early evidence thus far suggests that cannabis compounds are effective against several types of leukemia. Unfortunately, the global restrictions on cannabis cultivation place serious limits on scientific research around the world.
Research barriers are a major problem, as early research into the cannabis plant has found that compounds in the herb not only successfully reduce tumors in rodents and kill cancer cells in the lab, but they are also considered non-toxic. This is not true for chemotherapy.
Now, early laboratory findings need to be tested in blinded and controlled clinical trials in humans.
Interestingly, while chemotherapy targets both cancerous and healthy cells, research in brain cancer suggests that cannabis only targets diseased cells and leaves healthy cells alone.
Research thus far suggests that cannabis kills cancer cells in four distinct ways. Thus far, only two of these mechanisms have been studied in regard to leukemia. Here’s what they are:
Once they get started, cancer cells keep on growing. In 2016, an experiment published in BioMed Central Cancer found that the psychoactive component in cannabis, THC, successfully halted the proliferation of leukemia cell cultures.
The study used the drug dronabinol, which is a synthetic drug designed to resemble and mimic the effects of THC. The researchers found that the drug was most effective in acute lymphoblastic and myeloid leukemia cells, and the study authors ultimately concluded:
Our study provides rigorous data to support clinical evaluation of THC as a low-toxic therapy option in a well-defined subset of acute leukemia patients.
The study also found that THC was effective against leukemia cells on a broad scale, decreasing proliferation and causing cancer cells to self-destruct. The researchers also found that these results are achievable in vivo, meaning inside a living organism. This is promising research for future trials of cannabis-based leukemia drugs.
2. Cell suicide
Normally, cells that are old, diseased, or infected die. There are a couple of ways that cells naturally self-destruct under the right conditions. One way is apoptosis, which can be loosely defined as cell suicide. Unfortunately, cancer cells stop responding to these automatic death signals. Instead, they continue to grow and proliferate.
Cannabis may put a stop to this. Cancer research has shown that cannabis compounds can trigger apoptosis in tumor cells, which is a hallmark of an effective cancer drug. In 2006, a study published in Molecular Cancer Research found that THC treatment successfully triggered apoptosis in cultured leukemia T cells.
Additional research published in Blood has shown that the anti-cancer effects of THC against leukemia cells begin just a short six hours after treatment. In this study, all leukemia cell lines responded to THC treatment.
3. Anti-metastatic and anti-angiogenesis
Leukemia is a bit different than other cancers. While most cancers begin to develop tumors which can then break apart, travel, and infect other parts of the body, Leukemia causes diseased blood cells to flow throughout the body. In other forms of cancer, cannabis compounds have been found to inhibit cancer and tumor formation via two additional mechanisms.
Research has shown that cannabis compounds are anti-metastatic, which prevents tumor cells from infecting other areas after a tumor develops. In the laboratory, cannabis compounds also prevent tumor cells from establishing blood vessels. Without blood vessels, the tumors starve.
While these traits are not necessarily pertinent to all forms of leukemia, they may prove useful when and if cancer cells move outside of the blood and form tumors. However, further research on tumors related to leukemia is needed.
Cannabis for leukemia symptom management
Whether or not cannabis is effective against leukemia in humans, there are a few ways that the herb can help reduce pain and other debilitating side effects of chemotherapy. Some of these symptoms include: