WASHINGTON -- The growth of cancer cells slowed to the point of cellular "suicide" when scientists inserted a small genetic mutation, Reuters reported on Friday.

"it's almost like a poison spike," said Dr. Elizabeth Blackburn, a professor of biochemistry and biophysics at the University of California, San Francisco, who led the study. "You only have to add a little bit to get a nasty effect."

The mutation targeted an enzyme highly active in cancer cells called telomerase, which helps to preserve chromosome structures during the corrosive process of cell replication.

The mutation used telomerase to destroy rapidly multiplying cancer cells -- a strategy Blackburn compared to the Japanese martial art jujitsu, where opponents use their rivals' force to defeat them.

In the study, scientists inserted a small mutation into the enzyme's genetic coding, composed of ribonucleic acid (RNA). the mutated RNA thwarted the normal activities of telomerase in translating RNA to DNA in order to rebuild portions of the chromosome lost in cell replication.

"Cancer cells are kind of famous for resisting signals that tell them to commit suicide, that's one of the things that makes them so dangerous," Blackburn said. "It was quite a surprise to have this small amount of telomerase be so effective."

Low levels of the mutant RNA dramatically decreased growth rates of breast and prostate cancer cells in the study and made more cells die.

The mutation resulted in smaller breast cancer tumors in live mice implanted with the mutated enzyme.

While an explanation for the impact of telomerase mutation on cancer cell growth remained unclear, Blackburn said future research may find that cancer cells from living humans are more susceptible to the mutant enzyme than the laboratory-grown cells used in the study.

Scientists have been studying several approaches to treating cancer by disrupting telomerase activities, but this University of California study also may produce new therapy approaches, according to a commentary published with the study.

Among the options being studied, telomerase mutation offered "a clear theoretical advantage as an approach for treating cancer with immediate impact on tumor cells," Richard Hodes of the National Institutes of Health wrote.