Cannabis destroys cancer cells

Research at Barts and The London, Queen Mary's School of Medicine and Dentistry reveals

01 March 2006

Researchers investigating the role of cannabis in cancer therapy reveal it has the potential to destroy leukaemia cells, in a paper published in the March 2006 edition of Letters in Drug Design & Discovery. Led by Dr Wai Man Liu, at Barts and the London, Queen Mary’s School of Medicine and Dentistry, the team has followed up on their findings of 2005 which showed that the main active ingredient in cannabis, tetrahydrocannabinol, or THC, has the potential to be used effectively against some forms of cancer. Dr Liu has since moved to the Institute of Cancer in Sutton where he continues his work into investigating the potential therapeutic benefit of new anti-cancer agents.

It has previously been acknowledged that cannabis-based medicines have merit in the treatment of cancer patients as a painkiller; appetite stimulant and in reducing nausea, but recently evidence has been growing of its potential as an anti-tumour agent. The widely reported psychoactive side effects and consequent legal status of cannabis have, however, complicated its use in this capacity. Although THC and its related compounds have been shown to attack cancer cells by interfering with important growth-processing pathways, it has not hitherto been established exactly how this is achieved.

Now Dr Liu and his colleagues, using highly sophisticated microarray technology – allowing them to simultaneously detect changes in more than 25,000 genes in cells treated with THC – have begun to uncover further the existence of crucial processes through which THC can kill cancer cells and potentially promote survival. Further, Dr Liu found that the mechanism of cannabis may be independent of the presence of receptors – proteins found on the surface of cells to which other signalling molecules bind. Binding of molecules to receptors elicits a response in the cell, be it growth or death. The finding that cannabis action may not require the presence of these receptors introduces the possibility that the drug may be used more widely as the cancer cell’s dependence on the cannabis receptor is removed.

Whilst leukaemia treatment is on the whole successful, some people cannot be treated with conventional therapy - 25 per cent of children with leukaemia fail to respond to traditional treatment leaving their prognosis outcome poor. Dr Liu’s research findings provide a crucial first step towards the development of new therapies that can eradicate a deadly disease which affects millions of children and adults worldwide.

Dr Liu said: “It is important to stress that these cannabis-like substances are far removed from the cannabis that is smoked. These novel compounds have been specifically designed to be free of the psychoactive features, whilst maintaining anti-cancer action. Ultimately, understanding the fundamental mechanisms of these compounds will provide us with insights into developing new drugs that can be used to effectively treat cancers.”
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For further information, please contact:

Alexandra Fernandes
Deputy Head of Communications
Queen Mary, University of London
Tel: +44 (0) 20 7882 7910
email: a.fernandes@qmul.ac.uk

Notes to Editors:

Queen Mary, University of London

• Queen Mary is one of the leading colleges in the federal University of London, with over 11,000 undergraduate and postgraduate students, and an academic and support staff of around 2,600.

• Queen Mary is a research university, with over 80 per cent of research staff working in departments where research is of international or national excellence (RAE 2001). It has a strong international reputation, with around 20 per cent of students coming from over 100 countries.

• The College has 21 academic departments and institutes organised into three sectors: Science and Engineering; Humanities, Social Sciences and Laws; and the School of Medicine and Dentistry.

• It has an annual turnover of £200 million, research income worth £43 million, and it generates employment and output worth nearly £400 million to the UK economy each year.

• Queen Mary’s roots lie in four historic colleges: Queen Mary College, Westfield College, St Bartholomew’s Hospital Medical College and the London Hospital Medical College.

Institute of Cancer, Barts and the London, Queen Mary's School of Medicine and Dentistry

Created in 2003 the Institute of Cancer brings together some of the most eminent cancer research teams in London across six research centres. Under the leadership of the Director, Professor Nick Lemoine, and supported by an Executive Board of senior investigators, it is creating the academic environment fitting for an internationally recognised, comprehensive cancer centre. Its Cancer Research UK Clinical Centre – the first such international centre of excellence to be established in the UK - is the largest group of Cancer Research UK clinical and translational groups in London. The Institute is supported by a host of charities, research councils and industry with grants awarded totalling more than £5million per annum.

Microarray technology

A microarray is a slide on which have been embedded thousands of probes specific for all the genes found within a cell. Dr Liu’s data showed that certain pathways involved in cell survival were acted upon by cannabis, resulting in the death of the cell.