Cal27, SCC4 and SCC9 cells as well as 293T cells were obtained from ATCC (Manassas, VA, USA). UM1 cells were purchased from Japanese Collection of Research Bioresources (JCRB) cell bank (Osaka, Japan), and normal human oral keratinocyte (NHOK) was supplied by ScienCell Research Laboratories (San Diego, CA, USA). Above cells were cultured in Dulbecco’s Modified Eagle Medium (DMEM, PAN Biotech, Aidenbach, Germany) added with fetal bovine serum (FBS; 10%, HyClone, Logan, UT, USA) at 37 °C with 5% CO2.
Mimic of miR-26a (miR-26a) or miR-26b (miR-26b) and the mimic negative control (miR-NC), inhibitors of miR-26a (anti-miR-26a) or miR-26b (anti-miR-26b) and the inhibitor negative control (anti-miR-NC) and pcDNA-PAK1 (PAK1) were acquired from GenePharma Co., ltd. (Shanghai, China). And the pcDNA empty vector (pcDNA) was purchased from Thermo Fisher Scientific (Waltham, MA, USA). SCC4 and Cal27 cells were sowed into 6-well plates (about 2 × 106 cells/well) and transfected with aforementioned nucleotides or plasmids when confluence reached 70–80% using Lipofectamine 2000 (Life Technologies Corporation, Carlsbad, CA, USA) referring to manufacturer’s recommendations.
Mimic of miR-26a (miR-26a) or miR-26b (miR-26b) and the mimic negative control (miR-NC), inhibitors of miR-26a (anti-miR-26a) or miR-26b (anti-miR-26b) and the inhibitor negative control (anti-miR-NC) and pcDNA-PAK1 (PAK1) were acquired from GenePharma Co., ltd. (Shanghai, China). And the pcDNA empty vector (pcDNA) was purchased from Thermo Fisher Scientific (Waltham, MA, USA). SCC4 and Cal27 cells were sowed into 6-well plates (about 2 × 106 cells/well) and transfected with aforementioned nucleotides or plasmids when confluence reached 70–80% using Lipofectamine 2000 (Life Technologies Corporation, Carlsbad, CA, USA) referring to manufacturer’s recommendations.