Gene expression by real-time PCR
Total RNA was extracted from primary cultured cells using a RNeasy® Mini Kit (Qiagen, Cat. no. 74106), and complementary DNA was synthesized from 1 µg of RNA using the RNA to cDNA EcoDryTM Premix (Takara, Cat. no. 639543). Gene expression assay was conducted using SYBR Green on QuantStudio 3 (Applied Biosystems, Model no. A28132), and relative cycle threshold (CT) values were normalized by GAPDH. The primers used in this study are listed in Supplementary Table 2.