Combining CBD with Chemotherapy Posts Promising Results in Pancreatic Cancer Model
Aug 09, 2018 | By Alexander Beadle
Cannabidiol (CBD) and other CBD-containing cannabis products have already been shown to be effective at mediating pain and reducing inflammation in clinical trials, and preclinical studies also indicate the drug’s potential for treating the symptoms of anxiety, depression, and psychosis. Spurred on by the demonstratively large variety in therapeutic properties of CBD, research into the effectiveness of medicinal cannabis is a hot topic. One of the largest fields of study for cannabis researchers is cancer research.
Several studies have already been carried out investigating the effects of CBD on different types of cancer cells. It has already been found to inhibit carcinoma growth in prostate cancer cell cultures, and induce apoptosis in breast cancer and leukemia cells.
Pancreatic cancer is the 11th most common cancer diagnosis globally, and is responsible for around 331,000 deaths per year. The average five-year survival rate after diagnosis is currently only 6%, with only a very slight variation between developed and developing countries. With no significant improvements seen in the life expectancy and survival rates of patients with pancreatic cancer over the past few decades, new work from a coalition of researchers in the UK, Italy, and Australia examines the effect of CBD on pancreatic cancer cells to examine whether this could lead to improved outcomes for those people affected by this aggressive cancer.
The Effect of Cannabidiol Treatment on Life Expectancy
The team studied pancreatic cell cultures as well as mice that had been genetically modified to develop pancreatic cancer. The sample group consisted of 34 mice, which were split into 4 smaller groups for treatment. Ten of the mice were given CBD and eight were given the chemotherapy drug gemcitabine, which is more commonly known by its brand name, Gemzar. A further seven mice were given a combination of both CBD and gemcitabine, and nine were given a placebo.
The mice in the placebo group survived for an average of 19 days. The mice that received CBD only survived for around 25 days, and the mice who were given gemcitabine chemotherapy treatment lived for approximately 28 days. The mice who received a combination of CBD and chemotherapy on average lived for almost 53 days. This is nearly three times as long as the mice given the placebo, and around twice as long as the mice given CBD or chemotherapy alone.
GPR55 Signaling and Cancer Proliferation
As well as studying the survival rates of the mice, the GPR55 gene was also examined as it has previously been recorded as being involved in many of the cellular functions associated with cancer proliferation. The gene produces proteins inside cell membranes that can act as detectors for various substances, including cannabinoids such as CBD. Immunohistochemistry analysis showed an accumulation of GPR55 in human cancer cell lines compared to healthy human cell lines, which lends further weight to the notion that GPR55 may be involved in the proliferation of cancer cells.
The researchers found that CBD can block the receptors that are produced by the GPR55 gene. This prevents the proteins from interacting synergistically with other compounds to promote the proliferation of pancreatic cancer cells. As a result, this inhibition of the GPR55 signaling pathway slows the growth and multiplication of these typically aggressive cancer cells.
Additional Considerations for CBD Use
In the past, there have been recorded cases of cell lines developing a resistance to gemcitabine treatment. As gemcitabine is one of the most common chemotherapy drugs prescribed for pancreatic cancers, the potential for pancreatic cancer cells building up a resistance to the drug is highly concerning. In the interest of combatting this, the researchers in this study also examined the effects of CBD on activation pathways that are thought to be associated with gemcitabine resistance, such as increased ERK activity. The team found that CBD was able to decrease ERK activity, and as a result, could hinder at least one of the potential pathways to chemotherapy resistance.
As well as the increased life expectancy and decreased drug resistance, Professor Marco Falasca, the corresponding author on the research project, also emphasized additional benefits to using CBD in conjunction with traditional chemotherapy drugs.
Speaking to Analytical Cannabis, Professor Falasca explained, “Cannabidiol is also known to improve the side effects of chemotherapy, including nausea, diarrhea, and vomiting, meaning it could also improve the quality of life of patients undergoing chemotherapy.”
Professor Falasca also addressed the practicalities of using CBD together with chemotherapy treatments, stating “cannabidiol is also already approved for use in clinics, which means we can quickly go on to test this in human clinical trials. If we can reproduce these effects in humans, cannabidiol could be in use in cancer clinics almost immediately, compared to having to wait for authorities to approve a new drug.”