UCSF researchers published work in PNAS this week showing findings that miRNAs can, in some cases, induce gene expression. In their study they identified miR-373 target sites in the promoter regions of both E-cadherin and cold-shock domain-containing protein C2 (CSDC2) genes. Transfecting miR-373 into PC-3 cells induced gene expression at both sites, revealing a surprising new way that miRNAs can regulate expression.