Cell culture

The RCC cell lines 786–0 and ACHN were purchased from Cell Bank of Type Culture Collection of Chinese Academy of Sciences (Shanghai, China), were cultured in RPMI-1640 (Sigma-Aldrich, St. Louis, MO, USA) supplemented with 10% fetal bovine serum (FBS; Gibco; Thermo Fisher Scientific, Inc., Waltham, MA, USA) and 1% antibiotics (100,000 U/l penicillin and 100 mg/l streptomycin; Thermo Fisher Scientific, Inc.). Cells were cultured at 37°C in a humidified atmosphere containing 5% CO₂. Cells of the exponential phase of growth were used in the subsequent experiments.