Current treatments for cancer and viral infection are limited remedies that often suppress cell or viral replication rather than eliminate diseased cells entirely from the body. A further limitation is that these therapies often compromise healthy cells as well, leaving problems of recurrence and side effects.
Researchers at developed a novel therapeutic nanoparticle (NP) system harboring therapeutic small siRNA that can significantly enhance effectiveness and specificity of treatments by killing diseased cells.
Nanoparticles attached to RNA/DNA hybrids encode recognition sites for target genes and partial siRNA sequences of human anti-apoptotic genes. Individually, each of the hybrids is functionally inactive and functional representation can only be activated by the re-association of at least two cognate hybrids simultaneously present in the same cell. Overall, this novel approach allows each NP to have recognition sites for different target genes (e.g. viral genes in viral infection, abnormally regulated genes in cancer), providing versatile options for selecting cells to kill with far greater specificity. Besides therapeutic siRNA, RNA/DNA hybrids on NPs can encode fluorescent markers to specifically visualize the diseased cells.