Researchers at the Tel Aviv University (TAU) and Berlin’s Frei University found that cancer cells can remain dormant or “switched off” by a nanomedicine that contains cancer-inhibiting microRNAs. They hope that this will be used as a universal approach in treating cancer.

The study, published in the journal ACS Nano in Jan. 27. explains that the amount of three microRNAs were low in osteosarcoma cancer cells but high in the dormant tumour tissue. They inserted the microRNA into the tumour tissues and discovered that the cancer cells stopped spreading. The mice treated with the nanomedicine lived for six months; this is equivalent to 25 human years.

“We saw that the osteosarcoma cells treated with the selected microRNAs were unable to recruit blood vessels to feed their growth,” according to Ronit Satchi-Fainaro , Chair of the Department of Physiology and Pharmacology at TAU’s Sackler Faculty of Medicine and Head of TAU’s Cancer Angiogenesis and Nanomedicine Laboratory.

“In order to keep these microRNAs stable in the blood, we needed to encapsulate them in a nanoparticle that circulates in healthy blood vessels, but that disembark and deliver the drug therapy at the leaky blood vessels that exist at tumour sites. We designed a nanomedicine that would have a special activation method at the tumour site in the target cell,” Satchi-Fainaro adds.

Satchi-Fainaro notes that cancer remains manageable as long as cancer cells are still asymptomatic and dormant. However, once osteosarcoma spreads, the only management is to prolong life instead of curing the actual disease. The researchers are currently studying other tumour types and aims to start the study’s clinical trials.

Osteosarcoma is one of the most aggressive cancers, which affects the bones of children and adolescents. Eight hundred people from the US are diagnosed with the cancer annually but effective treatments remain to be unavailable so patients have only a 15 percent five-year survival rate.