**3. Results**

#### **3.1 miR-665 inhibits cell proliferation**

NB cells transfected with miR-665 show changes in cell morphology, lost the normal spindle shape and cells grew in clumps without processes compared to cells transfected with negative control miRNA **(Figure 1A** and **B**). Cell cycle analysis results show that miR-665 treated cells show an increase of 16% of cells in G1 phase of cell cycle and the cell number decreased by 18% in S phase compared to negative control miRNA transfected cells. miR-665 treatment did not affect the cells in G2 phase (**Figure 1C**). Cell viability decreased proportionally with the increasing concentration of miR-665, represented by black bars (**Figure 1D**)**.**
