Cannabinoids Shrink Tumors in New Study

CBD could be used to treat melanoma tumors, according to a new study from the Augusta University Medical Center, Georgia.

The research demonstrated that cannabidiol (CBD) can effectively reduce the size of tumors in mice and increase the chances of recovery.

The cannabinoid’s effects still paled in comparison to cisplatin’s, a more conventional chemotherapy medication, but the researchers claim that subjects given CBD-chemotherapy had a higher quality of life.

The study was conducted on mice and published in the Journal of Surgical Research.

Mapping melanoma

Skin cancer is the most common and deadliest form of cancer in the world. Outpacing almost all other cancers, rates of diagnosis for the disease have increased dramatically over the past three decades. In 2018 alone, 91,270 people were expected to be diagnosed with new melanomas in the United States.

Aggressive and complex, the disease can be divided into two groups: melanoma and nonmelanoma skin cancers. The former, and target of the researchers’ study, develops after skin cells called melanocytes mutate and multiply, forming life-threatening tumors.

Of course, melanoma tumors aren’t necessarily fatal. Thanks to modern treatments, nine out of ten patients now live beyond the first ten years of their diagnosis.

This treatment usually involves some surgery to remove the tumor, lymph nodes, or any other area that the cancer has spread to. But more advanced tumors may require radio- and chemo-therapy. In these cases, a patient’s course of radiation will leave them with pain, fatigue, and hair loss.

But, according to the Georgia researchers, these sickly symptoms could soon become side effects of the past.

Shrinking tumors

Cancer research is dependent on studying cancerous cells, tissues and subjects. But to study a cancerous subject, one must be created.

After acquiring a group of lab mice, the Georgia researchers injected the subjects with a melanoma cell line, which soon triggered tumor growth. The mice were then split into groups and given either a CBD, cisplatin or placebo treatment. The size of the tumors were measured continually until they reached 12mm in length, at which point, under the animal care guidelines at the university, the mice were euthanized.

The placebo group were the first to go, lasting an average of 15 days. Second came the mice treated with CBD, which had an average survival time of 19 days, leaving the cisplatin-treated mice as the longest living group, with an average life span of 24 days.

This pattern was mirrored in the size of the tumors. While the CBD treatment did reduce the cancerous growth, after 14 days the mice given cisplatin had the smallest tumors, followed by the CBD and placebo groups.

Despite this, the researchers claim that the CBD-given mice still had a higher quality of life. Of all the subjects, mice given the CBD treatment were reported to have improved movement and fewer fights and hostile interactions – the laidback symptoms one might expect from a mouse given cannabinoids.

CBD for melanoma 

While enlightening and the first of its kind, the study was not without its flaws, and even the researchers admit that there were many limitations.

For example, cases of advanced melanoma are often treated with two drugs at the same time in a process called combined therapy. As the mice were only given CBD by itself and not in conjunction with another anti-cancer drug, it’s difficult to make bold claims about its practical effects in a real clinical setting.

Euthanizing the mice can also be considered a limitation. Instead of recording all the potential data that a subject could provide over its lifespan, every mouse was killed after their tumors reached 12mm. This caveat prevents the data from being an accurate measurement of survival and is instead more a record of an arbitrary endpoint of growth.

Both these factors leave the study’s results too far removed from clinical reality to be considered for human treatment. But the researchers do stress that this was a small pilot study purely evaluating the effect of CBD in an animal model.

Now, after the tumor-reducing effects of CBD have been demonstrated for the first time, the hope is that more groups will take up research area and progress the scientific understanding of CBD to a point where it may be effectively used in melanoma treatments.