Sirnacontrol si nc

Small interfering RNA (siRNA) against circPRRX1 (si-circPRRX1), siRNA control (si-NC), miR-3064-5p mimics (miR-3064-5p), mimics control (miR-NC), miR-3064-5p inhibitor (anti-miR-3064-5p), inhibitor control (anti-miR-NC), PTPN14 overexpression vector (PTPN14), and empty overexpression vector (vector) were purchased from GenePharma (Shanghai, China). Lipofectamine 3000 (Invitrogen, Carlsbad, CA, USA) was used to transfect oligonucleotides or vectors into cells.

HCC cell line SMMC7721, HepG2, human NK cell line NK-92, and 293T cells were purchased from American Type Culture Collection (ATCC, Manassas, VA, USA). SMMC7721, HepG2, and 293T cells were maintained in DMEM with 10% heat-inactivated fetal bovine serum (FBS; Sigma-Aldrich, St. Louis, MO, USA) and 1% penicillin/streptomycin. NK-92 cells were maintained in α-minimum essential medium (Invitrogen, Carlsbad, CA, USA) supplemented with 12.5% FBS (Sigma-Aldrich), 12.5% horse serum (Gibco, Grand Island, NY, USA), 100 U/mL recombinant human IL (rhIL)-2 (PeproTech, Rocky Hill, NJ, USA), and 0.1 mM β-mercaptoethanol. The isolated primary NK cells were cultured in complete RPMI medium (Gibco) supplemented with 10% heat-inactivated FBS (Sigma-Aldrich), 2 mM L-glutamine, and 100 U/mL rhIL-2 (PeproTech). All cells were incubated at 37℃ in an incubator of 5% CO₂.
miR-506 mimic (miR-506), miRNA negative control (miR-NC), miR-506 inhibitor (anti-miR-506), inhibitor control (anti-miR-NC), pcDNA-STAT3, pcDNA empty control (pcDNA), siRNA specially against STAT3 (si-STAT3), and siRNA control (si-NC) were purchased from GenePharma (Shanghai, China). NK-92 and primary NK cells were seeded into 96-well plates and transfected with the abovementioned nucleotides or plasmids, using Lipofectamine 2000 (Invitrogen). Co-culturing or RNA extraction was performed 48 hours after transfection.