A Headline in the June 12, 2009, Issue of Science

Essay

A headline in the June 12, 2009, issue of Science Daily proclaimed that "MicroRNA Replacement Therapy May Stop Cancer in Its Tracks." The article described a study in which a virus was used to deliver a microRNA gene to cancerous and noncancerous liver cells in mice. Aggressive liver tumors were stopped in their tracks in 8 out of 10 treated mice. Explain how delivery of a gene encoding microRNA might be able to reduce the growth of cancer cells.