See, when cells get old and prepare to die, they're supposed to stop dividing. This process is controlled by "biological processors" called microRNAs which feed the cell just enough of the PLEKHA7 protein to inhibit division. But in the case of cancer, the microRNAs don't deliver enough of the protein and the cells begin to divide out of control, resulting in a tumor. In a recently published study in the journal Nature Cell Biology, the Mayo Clinic team found that by injecting microRNA directly into a tumor, PLEKHA7 levels returned to normal and the cancerous cells stop reproducing.

"This is an unexpected finding," Chris Bakal, a specialist at the Institute for Cancer Research in London, told The Telegraph. "Normal cells touch each other and form junctions, then they shut down proliferation. If there is a way to turn that [process] back on, it would be a way to stop tumors from growing."

What's more, the method has shown to be surprisingly effective against some especially aggressive forms of cancer, at least in initial lab tests. However, the researchers don't believe this will be some magic bullet that cures cancer outright. "This important study solves a long-standing biological mystery, but we mustn't get ahead of ourselves," Henry Scowcroft, Cancer Research UK's senior science information manager, told The Telegraph. "There's a long way to go before we know whether these findings, in cells grown in a laboratory, will help treat people with cancer. But it's a significant step forward in understanding how certain cells in our body know when to grow, and when to stop. Understanding these key concepts is crucial to help continue the encouraging progress against cancer we've seen in recent years." Still, any step forward in the fight against this disease will be a welcome one.

[Image Credit: Scott Tysick / Getty Creative]