Researchers have synthesised a novel type of DNA nanostructure that can inhibit the activities of specific cancer-causing tiny RNA molecules, making it potentially useful for treating cancers1.

MicroRNAs (miRNAs) are non-coding tiny RNA molecules that regulate the expression of many genes involved in various cellular processes, including diseases such as cancer. Recent studies have designed inhibitor molecules that can silence one type of cancer-triggering miRNA. However, such molecules cannot suppress cancers caused by multiple miRNAs.

To find an inhibitor molecule that can arrest cancer by blocking the activities of multiple miRNAs, scientists from the CSIR-Institute of Minerals and Materials Technology, Bhubaneswar, and the CSIR-Institute of Genomics and Integrative Biology, Delhi, led by Umakanta Subudhi and Souvik Maiti, prepared branched DNA nanostructures through a self-assembly process.

They modified the nanostructures in such a way that they can selectively bind to specific miRNAs that trigger breast cancer by silencing FOXO1a, a tumour-suppressor gene that encodes FOXO1a protein. This protein regulates glucose metabolism and other vital biological processes, but its levels are reduced in cancer cells.

In cell culture, the nanostructures retained their stability even after 36 hours and restored the levels of FOXO1a protein, inhibiting the activities of specific miRNAs that are known to initiate the unbridled growth of the cancer cells.

Being biocompatible and easily modifiable, the nanostructures are potential candidates for developing safe cancer therapies, says Subudhi.