Total RNA from cultured cells or tissues was isolated using the Qiagen miRNeasy kit. RNA was reverse transcribed with Moloney-murine leukemia virus (Promega). Real-time PCR for miRNA and mRNA were performed as described before (17 (link)). Briefly, mRNA SYBR green quantitative real-time PCR (Applied Biosystems) was performed to detect expression of mRNA levels in a HT7900 Fast Real-Time PCR System. 18S was used as the internal control. miRNA quantitative real-time PCR was performed according to the instruction of miRNA assay kit (Applied Biosystems) with snoRNA202 as the internal control.