Bel 7402

The human HCC cell lines BEL7402 and BEL7404 were purchased from the Cell Bank of the Chinese Academy of Sciences. Cells were incubated at 37 °C in a humidified atmosphere containing 5% CO₂ and cultured in DMEM (Gibco, ThermoFisher Scientific, Inc., Grand Island, NY, USA) combined with 10% fetal bovine serum (FBS). miR‐204‐5p mimics and inhibitors were purchased from QIAGEN. For transient transfection of cells in six‐well plates, 100 μm mimics or inhibitors was added with HiPerFect reagent (QIAGEN) in OPTI‑MEM media (Gibco; ThermoFisher Scientific, Inc.) according to the manufacturer's instructions. The cells were plated in 10‐mm² dishes and transfected with miR‐204‐5p overexpression and inhibition lentivirus (GeneChem, Shanghai, China). The inhibition lentivirus we used resulted in competitive inhibition. The stable cell lines were cultured with DMEM containing 2 μg·mL⁻¹ puromycin (Merck Millipore, Darmstadt, Germany). The SIX1 siRNA were purchased from GenePharm (Shanghai, China), and sequences are as follows: si1, 5′‐AGAAUAGUUUGAGCUCCUG‐3′ si2, 5′‐CACGCCAGGAGCTCAAACT‐3′ and Si3, 5′‐CCAGCTCAGAAGAGGAATT‐3′.

The liver cancer cell lines SMMC-7721, HepG2, Bel-7402, Bel-7404, Huh7, and SK-Hep1 and hepatocyte lines THLE-3 and HL-7702 were purchased from the Cell Bank of the Chinese Academy of Sciences (Shanghai, China). All the cells were cultured in DMEM (Hyclone, Logan, UT, USA) supplemented with 10% FBS (GIBCO, Carlsbad, CA, USA) and penicillin/streptomycin (GIBCO). Cells were treated with Cycloheximide (CHX, Sigma, St Louis, MO, USA) at a final concentration of 0.1mg/ml and MG132 (Cayman Chemical Co., Ann Arbor, MI) at a final concentration of 25 µM. NMT1- and NMT2-exprssing plasmids were purchased from Origene (Beijing, China). The plasmids expressing NMT1-sh1, NMT1-sh2, POTEE-sh1, POTEE-sh2, RPL7A-sh1, RPL7A-sh2, HBB-sh1, HBB-sh2, HIST1H4H-sh1, and HIST1H4H were purchased from Genechem (Shanghai, China). The expressing plasmids of LXN-HA, FAU-HA, RPL29-HA, LXN-Mut-HA, FAU-Mut-HA, RPL29-Mut-HA, AHSG-HA, ALB-HA, TF-HA, AHSG-Mut-HA, ALB-Mut-HA, TF-Mut-HA, POTEE-Myc, RPL7A-FLAG, HBB-FLAG, HIST1H4H-HA, and HIST1H4H-Mut-HA were purchased from Biolink (Shanghai, China).

The human HCC cell lines BEL-7402, HuH-7, PLC/PRF/5, and SMMC-7721 were purchased from the Cell Bank of the Chinese Academy of Sciences (Shanghai, China). The HCC cell line MHCC97H was kindly provided by Prof. Jia Fan from Zhongshan Hospital of Fudan University. The cells were maintained in Dulbecco modified Eagle medium (DMEM) supplemented with 10% fetal bovine serum (FBS), 100 U/mL penicillin, and 100 μg/mL streptomycin sulfate in a humidified incubator at 37°C in an atmosphere containing 5% CO₂ in air. The suppliers and catalog numbers of all antibodies, chemicals, and reagents used in this study are listed in Supplementary Table 3.

HEK293T cells were purchased from the American Type Culture Collection (ATCC). The human HCC cell lines (HepG2 and BEL-7402) were obtained from the Cell Bank of the Chinese Academy of Sciences (Shanghai, China). These cell lines were cultured in Dulbecco’s modified Eagle’s medium (DMEM) (high glucose) supplemented with 10% fetal bovine serum (FBS) in a humidified incubator maintained at 5% CO₂ and 37°C.