Extracts from the yellow curry spice turmeric can kill off cancer cells, according to BBC News. New research from the Cork Cancer Research Centre shows that the extract can destroy oesophagus cancer cells in a lab.
Oesophageal cancer cells are often resistant to cell death (the aim of chemotherapy), so in this laboratory study the researchers investigated the effects of curcumin (the active extract from turmeric) on a range of different types of cancer cells from the gullet. Introducing the chemical induced a type of cell death, called mitotic catastrophe.
While it is too soon to call this a cure for cancer, the findings pave the way for further investigations into the potential of plant-derived substances that are able to induce cell death in cancer cells. This could be particularly important for treating cancers that have so far proved resistant to chemotherapy.
Where did the story come from?
The study was carried out by Dr Geraldine O’Sullivan-Coyne and colleagues from the Cork Cancer Research Centre at University College Cork, Mercy University Hospital and the Nencki Institute of Experimental Biology in Warsaw, Poland. The study was funded by the Higher Education Authority of Ireland and the Cork Cancer Research Centre, and was published in the peer-reviewed British Journal of Cancer.
What kind of scientific study was this?
This was a laboratory study investigating how oesophageal cancer cells respond when coming into contact with curcumin, a chemical found in the Indian spice turmeric.
Curcumin is one of a number of plant-derived chemicals, or phytochemicals, that have been studied for their anti-cancer properties. Previous research has shown that curcumin induces ‘cell death’ in malignant cells. Many tumour cells are resistant to cell death, and any substance that can change this without affecting healthy cells has potential as an anti-cancer agent.
Curcumin disrupts a number of cycles in cancer cell and causes a particular type of cell death known as mitotic catastrophe. This occurs when a cell divides into two (mitosis) and errors occur in the way the chromosomes separate. In most cases, when these errors occur various processes will interact to cause the cell to be destroyed.
Different concentrations of curcumin were mixed with a culture medium in which cancer cells were growing. In all of their experiments, the researchers also included control cultures without curcumin present in the medium, to use for comparison.
After 24 hours of treatment, the researchers investigated the viability of the cancer cells, if they were multiplying (their mitotic index) and the mechanisms of cell death.
What were the results of the study?
The study found that cancer cells substantially lost their viability after being incubated with curcumin for 24 hours. This action was clearly dose-dependent, meaning higher doses had a greater effect on the viability of the cells. Some cell lines were able to recover when allowed a 48-hour recovery period after curcumin treatment, but two particular cell lines could not recover from treatment at concentrations “greater than 15µM” (concentration by curcumin’s molecular weight per litre).
Further investigations of the nature cells’ reduced viability showed that they were largely undergoing mitotic catastrophe that led to cell death. This was accompanied by other instances of cell death through apoptosis (programmed cell death) or autophagy (degradation of cell by internal digestive enzymes), depending on the specific line of cancer cells tested.
What interpretations did the researchers draw from these results?
The researchers conclude that curcumin shows features of cytotoxicity (toxic to cells) that are consistent with the induction of mitotic catastrophe in certain lines of cancer cells. They say that because of its activity, it is likely that curcumin may be a realistic option for future consideration as a molecular method to prevent and treat cancer.
What does the NHS Knowledge Service make of this study?
This laboratory study exposed various different lines of oesophageal cancer to the chemical curcumin, which is an extract from the spice turmeric commonly used in Indian cooking.
- This was a well-conducted study, and it has furthered the understanding of the complex processes associated with cell death that has resulted from exposure to cytotoxic substances.
- Given the preliminary nature of this study, it is premature to herald the spice as a potential cure for cancer.
- In advance of research in humans, further study is needed to uncover the precise mechanisms behind this activity.
- The process for developing drugs for humans is a long and involved one, and chemicals that show promise in the laboratory (in vitro) do not always have the same effect when testing moves on to animals and eventually humans. There is some way to go before we fully understand the potential of this compound in the treatment of oesophageal cancer for humans.
Links to the headlines
Curry spice ‘kills cancer cells’. BBC News, October 28 2009
Links to the science
O’Sullivan-Coyne, O’Sullivan G, O’Donovan TR et al.Curcumin induces apoptosis-independent death in oesophageal cancer cells. British Journal of Cancer [advance online publication] October 6 2009