Natural Born Killers

Natural killer cells play important role in fight against stomach cancer

/ Author:  / Reviewed by: Joseph V. Madia, MD

(RxWiki News) Researchers at the University of Gothenburg, Sweden, have linked immune-system cells that react to a certain bacteria in stomach ulcers to a risk factor for developing stomach cancer.

The bacterium Helicobacter pylori, one of the most common bacterial infections worldwide, leads to inflammation in the stomach. To compound matters, carriers are generally symptom free until stomach ulcers have already developed from the bacteria.

Stomach cancer is often diagnosed at a late stage, meaning poor prognosis.

Åsa Lindgren, a researcher from the Department of Microbiology and Immunology, said researchers before weren't sure how the chronic inflammation caused by the bacteria affects stomach-cancer development.

The researchers looked at how natural killer (NK) cells -- a type of immune cell that recognizes and destroys tumor cells as well as those infected by viruses and bacteria -- reacted to Helicobacter pylori. They found the natural killer cells fought the stomach ulcer bacteria, producing cytokines, which are special-signal substances that defend against intruders.

High amounts of natural killer cells in tumour tissue have been linked to better prognosis in stomach cancer patients since these cells eliminate tumor cells, leading scientists to believe that reduced natural killer cells can increase stomach cancer risk by contrast.

The finding could mean better, more effective techniques for diagnosing stomach cancer at earlier stages, which could mean better prognosis for patients.

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Review Date: 
January 10, 2011
Last Updated:
January 10, 2011