2. Materials and methods 2.1 Cell culture Human embryonic liver cell line L02 and HCC cell line SMMC-7721 SAHA HDAC were obtained from Shanghai Institute of Cell and Biology, Chinese Academy of Science and maintained in RPMI supplemented with 10% fetal bovine serum at 37°C with 5% CO2. Human metastatic HCC cell line MHCC97-L and HCCLM6 were established at Liver Cancer Institute, Zhongshan

Hospital, Fudan University, Shanghai, P.R. China [14] and cultured in DMEM (Invitrogen, Carlsbad, CA) containing 10% fetal bovine serum at 37°C with 5% CO2. 2.2 RNA isolation and selleck chemicals reverse transcription-PCR Total RNA was extracted from cells using TRIzol reagent (Invitrogen, Carlsbad, California) and PS-341 mw reverse transcribed into single-stranded cDNA. PCR was done on cDNA using oligo(dT) priming and amplified with the primer pairs for a 436-bp fragment of OPN(forward primer 5′-GGACTCCATTGACTCGAACG-3′ and reverse primer 5′-TAATCTGGACTGCTTGTGGC-3′) and a 366-bp fragment of Glyceraldehyde-3- phosphate dehydrogenase (GAPDH) (forward primer 5′-ATCCCATCACCATCT TCCAG-3′ and reverse primer 5′-GAGTCCTTCCACGA TACC AA-3′). GAPDH was used as a control. Ten microliters

of PCR product was analyzed on 2% agarose gels. 2.3 RNA isolation and real-time quantitative RT-PCR RNA was isolated from cells using the TRIzol and was reverse transcribed into cDNA by oligo(dT) primer. QuantiTect SYBR Green PCR kit (Qiagen, Valencia, CA) and DNA Engine Opticon System (MJ Research, Reno, NV) were used for real-time PCR. Data were analyzed with Opticon Monitor

software version 1.02. TCL The thermal cycling conditions comprised an initial denaturation step at 95°C for 15 minutes and 45 cycles at 94°C for 15 seconds and 55°C or 57°C for 1 minute. The primers for c-Myb, OPN and GAPDH were shown in Table 1. GAPDH was used as a control and relative expression of genes was determined by normalizing to GAPDH according to the manufacturer’s instructions. Table 1 Primers of c-Myb and OPN for real-time quantitative RT-PCR Gene Primer sequence (5′→3′) Annealing temperature(°C) Product length (bp) c-Myb TACAATGCGTCGGAAGGTCG 55 201   GCGGAGCCTGAGCAAAACC     OPN GTGGGAAGGACAGTTATGAAACG 57 134   CTGACTATCAATCACATCGGAAT     GADPH ATGACCCCTTCATTGACC 55 131   GAAGATGGTGATGGGATTTC     2.4 Nuclear extracts and biotin-streptavidin DNA pull-down assay Oligonucleotide containing biotin on the 5′-nucleotide of the sense strand was used in the PCR amplification for human OPN promoter. The sequences of the primer were as follows: sense strand: 5′biotin-TGGAATACATCCAATTTAAGGGAG-3′; antisense strand 5′-GAATGCACAA CCCAGTAGCAAA-3′; which corresponds to positions -1488 to +185 of the human OPN promoter. Nuclear proteins were isolated from HCC cell line SMMC-7721 and HCCLM6 cells respectively according to manufacturer’s directions (NE-PER nuclear and cytoplasmic extraction reagents, Pierce).