MIR3686: MIR3686 is a microRNA that has been identified as a potential regulator for PLK1, a key regulator for cell mitosis [1]. In "gain of function" assays, inhibiting MIR3686 enhanced cell proliferation [1]. The 3′UTR of PLK1 mRNA, which contains the MIR3686 target sequence, was cloned to generate a PLK reporter [1]. In PANC1 cells, downregulation of MIR3686 was correlated with an increase in PLK1 mRNA expression [1]. Transfection of MIR3686 mimic inhibited the proliferation and colony formation of PANC1 cells [1]. The inhibition of PLK1 by MIR3686 could be achieved by increasing the dose or transfecting the cells multiple times [1]. In cell invasion assays, moderate inhibition of invasion was observed in MIR3686 transfected cells [1]. The expression level of MIR3686 in HPDE67 cells was higher compared to PANC1 cells and downregulation of MIR3686 could enhance cell proliferation and clone formation in HPDE67 cells [1].