Let-7 MicroRNA Family Is Selectively Secreted into the Extracellular Environment via Exosomes in a Metastatic Gastric Cancer Cell Line

PLOS ONE, October 2010

20949044

Keiichi Ohshima, Kanako Inoue, Akemi Fujiwara, Keiichi Hatakeyama, Kaori Kanto, Yuko Watanabe, Koji Muramatsu, Yorikane Fukuda, Shun-ichiro Ogura, Ken Yamaguchi, Tohru Mochizuki

Exosomes play a major role in cell-to-cell communication, targeting cells to transfer exosomal molecules including proteins, mRNAs, and microRNAs (miRNAs) by an endocytosis-like pathway. miRNAs are small noncoding RNA molecules on average 22 nucleotides in length that regulate numerous biological processes including cancer pathogenesis and mediate gene down-regulation by targeting mRNAs to induce RNA degradation and/or interfering with translation. Recent reports imply that miRNAs can be stably detected in circulating plasma and serum since miRNAs are packaged by exosomes to be protected from RNA degradation. Thus, profiling exosomal miRNAs are in need to clarify intercellular signaling and discover a novel disease marker as well.