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In a world first, scientists at Nottingham University, UK, are investigating whether cannabidiol - a non-psychoactive chemical in marijuana - could be used to shrink brain tumors, prompted by a growing number of parents administering it to their children for the purpose.

The team is led by Professor Richard Grundy of Nottingham University's children's brain tumor center, who said there had been a sizeable surge in parents administering it without medical advice in the belief it might help in 2017. Products containing cannabidiol can be bought online legally, as they do not contain THC, the ingredient in cannabis which induces the high.

In 2016, the Medicines and Healthcare Products Regulation Agency declared the compound had a "restoring, correcting or modifying" effect on "physiological functions." Still, the ruling meant companies must acquire a licence to sell them — they are officially classified as medicinal, and as such must meet safety, quality and efficacy standards.


While no research has previously been conducted into how cannabidiol can treat brain tumours, the ability of cannabis molecules to ease cancer suffering in patients has been documented.

There is an urgent need for new methods of treating childhood brain tumors, which kill more children in the UK than any other type of cancer — although the disease receives less than one percent of the UK's cancer research funding. Around 1,750 under-18s are diagnosed with cancer annually, of which about 400 are cancers of the brain and spinal cord.

The researchers will grow cells from different brain tumors in lab conditions, some with the addition of cannabidiol molecules and others without, and compare how the presence of tumour cells differs in both samples through a technique called "cell staining." This will show how many cells are dividing, and whether any are dying. If successful, cannabidiol products could provide a gentler, less toxic means of treating cancer than chemotherapy or radiotherapy.


"We expect the cells — brain tumor and normal brain — grown in our standard conditions to be healthy and actively dividing. We expect that normal brain cells grown in cannabidiol will remain healthy. However, we expect the brain tumour cells grown in cannabidiol to stop growing and die," Professor Grundy said.

Championing the research are the parents of William Frost, a four-year-old diagnosed with an ependymoma brain tumor in 2014. In 2016, doctors told them nothing more could be done for their son — unfazed, they began researching alternative treatments. Within six months of starting William on a concerted course of cannabidiol, his tumor had shrunk by two-thirds, and he is now able to attend school part-time.


It is not the first time the university has been involved in groundbreaking research into cannabis compounds. In 2010, researchers found chemicals in marijuana interacted with cells in the body that play an important role in gut function and immune responses. The human body products THC-like compounds that increase the permeability of the intestines, allowing bacteria in — plant-derived cannabinoids in marijuana block these body-cannabinoids, preventing this permeability and making intestinal cells bond together tighter.

While research into cannabidiol is in its relative infancy, to date its only reported negative side effect is an unpleasant dry sensation in the mouth. Smokers of marijuana, which in its THC-enriched form is potentially hazardous to mental health, know this phenomenon well — it is commonly referred to as "cotton mouth." In essence, cannabis and its constituent compounds inhibit saliva secretion, leading to aridity in the mouth.