Total RNA was extract from LO2 cells using TRIzol (Invitrogen; Thermo Fisher Scientific, Inc.) according to the manufacturer's protocol. A total of 3–5 µg of RNA was transcribed into cDNA using a RevertAid First Strand cDNA Synthesis kit (Thermo Fisher Scientific, Inc.). Reverse transcription was performed at 42°C for 60 min, followed by 70°C for 5 min. Primers used for RT-qPCR are listed in Table I. qPCR was conducted using the SYBR Green premix kit from Takara Bio, Inc. (Otsu, Japan). Thermocycling conditions were as follows: Initial denaturation at 95°C for 30 sec followed by 50 cycles of 95°C for 5 sec, 60°C for 30 sec and 72°C for 60 sec. Expression levels were normalized to β-actin in the same samples using the 2−ΔΔCq method (7 (link)).