Total RNA were extracted as described in qPCR section. The mRNA expression levels of VCAM-1, ICAM-1, KLF2 and GAPDH were detected. The specific sequences of primers of quantitative real-time PCR were designed as follows: hKLF2: sense, 5′-CACGCACACAGGTGAGAA-3′, antisense, 5′-ACAGATGGCACTGGAATGG-3′; hVCAM-1: sense, 5′-TCAGATTGGAGACTCAGTCATGT-3′, antisense, 5′-ACTCCTCACCTTCCCGCTC-3′; hICAM-1, sense, 5′-GGCCGGCCAGCTTATACAC-3′, antisense, 5′-TAGACACTTGAGCTCGGGCA-3′; hET-1: sense, 5′-AAGGCAACAGACCGTGAAA-3′, antisense, 5′- GTCTTCAGCCCTGAGTTCTTT-3′; mKLF2: sense, 5′-CGTACACACACAGGTGAGAAG-3′, antisense, 5′-TGTGTGCTTTCGGTAGTGG-3′; mVCAM-1: sense, 5′-ACTCCCGTCATTGAGGATATTG-3′, antisense, 5′- TGACAGTCTCCCTTTCTTTGAG-3′; mGAPDH: sense, 5′-AACAGCAACTCCCACTCTTC-3′, antisense, 5′- CCTGTTGCTGTAGCCGTATT-3′.