Cancer-killing molecules found

CHICAGO — Specific molecules called suicide RNA molecules can trigger a mechanism where it not only prevents cancer cells from becoming resistant to them, but also eliminates multiple genes that cancer cells need to survive, researchers at the US Northwestern University (NU) have discovered.

NU researchers used a specific class of small RNAs to suppress gene activity, and found that not only did many of these small RNAs suppress the gene they were designed against, but they also killed all cancer cells.

Researchers also found these special sequences can be found throughout the human genome, embedded in multiple genes.

These RNA suicide molecules trigger a mechanism called “death by induced survival gene elimination,” which, if activated, they hypothesized, might eliminate cancer cells with little to no effect on normal cells.

To test this, researchers delivered the RNA suicide molecules to mice with human ovarian cancer. The results revealed reduced tumor growth with no toxicity to the treated mice, and tumors didn’t develop resistance to this type of cancer treatment.

“It’s like committing suicide by stabbing yourself, shooting yourself and jumping off a building all at the same time,” said NU scientist Marcus Peter. “You cannot survive.”

This study, published in eLife on Oct. 24, and two other new Northwestern studies in Oncotarget and Cell Cycle by the Peter group, described the discovery of the assassin molecules present in multiple human genes and their powerful effect on cancer in mice.

Researchers are now refining the treatment to increase its efficacy.

“Our research may be tapping into one of nature’s original kill switches, and we hope the impact would affect many cancers,” Peter said. “Our findings could be disruptive.”

“Nature must have developed a fail-safe mechanism to prevent cancer or fight it the moment it forms. Otherwise, we wouldn’t still be here.”

Peter and his team have spent eight years searching for the molecules. Xinhua/PNA