Mouthwash to fight cancer? Oral disinfectants induce apoptosis in human oral tumor cells

March 21, 2013

( —Patients who suffer from gingivitis are often advised to use disinfectant mouthwashes. In the future, the active ingredients in these products could be used in a completely different area: As scientists have reported in the journal Angewandte Chemie, Chlorhexidin and Alexidin increase programmed cell death and may be effective against cancers of the mouth and throat.

Sometimes researchers discover that established drugs have other effects in addition to those for which they were actually approved. For example acetylsalicylic acid (Aspirin) has commonly been used to treat pain and fever; more recently, however, it has also been prescribed to thrombosis-prone patients as a blood thinner. A team headed by Thorsten Berg is now convinced that many low-molecular drugs already in use demonstrate previously unrecognized activity toward interactions between proteins, which may be of therapeutic use.

The team of scientists from the University of Leipzig, the Max Planck Institute for Biochemistry, the Center for Integrated Protein Science Munich, the Helmholtz Center Munich, the Technical University Munich, and the ETH Zurich were out to use a protein– relevant for human health to demonstrate the interactions between two proteins whose interaction controls apoptosis, or programmed . Both proteins are from the same . The first protein, Bad, initiates apoptosis-promoting protein to inhibit it.

The researchers proceeded to screen a collection of over 4000 substances known as a compound library. The majority of the compounds in the library are small molecules in clinical use. Binding experiments were used to determine which of the substances inhibit the binding of the two . To determine the specificity of the "hits", their effects on other protein–protein interactions were also tested.

Berg and his co-workers were successful: Chlorhexidin, the active component in commercial oral such as Chlorhexamed, Chlorhexal, Periogard, Corsodyl, and Chlorohex; as well as Alexidin, the active component in Esemdent, both inhibit the binding of the apoptosis inhibitor to the apoptosis trigger. Chlorhexidin's effect is specific, while Alexidin has additional very weak effects on other proteins.

Why are apoptosis proteins interesting? Apoptosis is decreased in tumor cells, so the cells do not die off and continue to divide. One reason for this is that they produce too much of the apoptosis-inhibiting protein. In experiments with cultures of cells from various tongue and throat carcinomas, both compounds caused increased apoptosis. This effect is much stronger in the cancer cells than in healthy cells. It may be possible to use these drugs in therapeutic applications.

The researchers hope to find other protein-protein interactions that could be targeted with approved small-molecule drugs.

Explore further: A tricky tumor virus

More information: Berg, T. Oral Disinfectants Inhibit Protein–Protein Interactions Mediated by the Anti-Apoptotic Protein Bcl-xL and Induce Apoptosis in Human Oral Tumor Cells, Angewandte Chemie International Edition.

Related Stories

A tricky tumor virus

January 17, 2008

Epstein-Barr virus (EBV) is a human-pathogenic virus which belongs to the herpes virus family. Almost every adult carries EBV inside. With an infestation rate of more than 90 %, EBV is one of the most successful human viruses. ...

Refusal of suicide order: Why tumor cells become resistant

June 23, 2008

Cells with irreparable DNA damage normally induce programmed cell death, or apoptosis. However, this mechanism often fails in tumor cells so that transformed cells are able to multiply and spread throughout the body. Scientists ...

New strategy directly activates cellular 'death protein'

May 31, 2012

Researchers at Dana-Farber/Children's Hospital Cancer Center have devised a strategy to directly activate a natural "death" protein, triggering the self-destruction of cells. They say the development could represent a new ...

Recommended for you

New polymer creates safer fuels

October 1, 2015

Before embarking on a transcontinental journey, jet airplanes fill up with tens of thousands of gallons of fuel. In the event of a crash, such large quantities of fuel increase the severity of an explosion upon impact. Researchers ...

Researchers print inside gels to create unique shapes

September 30, 2015

(—A team of researchers at the University of Florida has taken the technique of printing objects inside of a gel a step further by using a highly shear-rate sensitive gel. In their paper published in the journal ...

How a molecular motor untangles protein

October 1, 2015

A marvelous molecular motor that untangles protein in bacteria may sound interesting, yet perhaps not so important. Until you consider the hallmarks of several neurodegenerative diseases—Huntington's disease has tangled ...

Anti-aging treatment for smart windows

October 1, 2015

Electrochromic windows, so-called 'smart windows', share a well-known problem with rechargeable batteries – their limited lifespan. Researchers at Uppsala University have now worked out an entirely new way to rejuvenate ...


Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.