Extracellular RNA as Regulators of Cellular Processes.

In order to determine the biological functions of extracellular RNA, we have designed and synthesized single- and double-stranded analogues of human extracellular RNAs and analyzed the influences of these analogues on both the proliferation and the viability of cultured human adenocarcinoma cells MCF-7. Transfection of MCF-7 cells by snoRNA analogues, which were targeted to de novo 2^′-O-methylation of nucleotides of pre-mRNA, resulted in a partial impairment of pre-mRNA splicing. SnoRNA analogues directed to rRNA induced 2^′-O-methylation of targeted nucleotides of rRNA. Transfection by Alu RNA reduced the viability of MCF-7 cells. These data emphasize the role of circulating RNA as efficient inter-cellular messengers and highlight the structures of circulating RNA as a promising basis for the development of new biologically active substances. [ABSTRACT FROM AUTHOR]