SW1990 cells were treated with 20 μM AG490 for 24 hours. Recombinant IL-6 (Peprotech, Princeton, NJ, USA) was dissolved in 5-10 mmol/L acetic acid to a concentration of 0.1-0.5 mg/ml and then diluted with the culture medium for experiments. Capan-2 cells were treated with 100 ng/mL IL-6 for 24 hours. MTT assay Cell viability was determined

by 3-(4,5-dimethylthiazole-2-yl)-2.5-diphenyltetrazolium bromide (MTT) assay. Pancreatic cancer cells were seeded in 96-well culture plates in culture medium. After 24 hours, the medium was changed to fresh culture medium containing either 20 μM/L AG490 or 100 ng/ml IL-6. MTT assays were performed 24, 48, and 72 hours after AG490 and IL-6 treatment. At the time of the assay, the cells were stained with 20 μL MTT (5 mg/ml) (Sigma, St Louis, MO, USA) AZD1480 price at 37°C for 4 hours and subsequently made soluble in 150 μL of DMSO. Absorbance

was measured at 490 nm using a microtiter plate reader (Wako, Osaka, Japan). The results were used to obtain cell growth curves. Quantification by real-time PCR Total RNA was isolated using TRIzol LS (selleckchem Invitrogen, Carlsbad, CA, USA). The concentration and purity of RNA was determined using a spectrophotometer. cDNA was synthesized with M-MLV reverse transcriptase HDAC inhibitor (Promega, Madison, WI, USA). Quantitative real-time polymerase chain reaction (RT-PCR) assays were carried out using SYBR Green Real-Time PCR Master Mix (Toyobo, Osaka, Japan) and realplex S RT-PCR amplification equipment (Eppendorf, Hamburg, Germany). The primers and amplicon sizes were as follows: MMP-2 sense strand 5′-TAG CAT GTC CCT ACC GAG TCT-3′, antisense strand 5′- ATT GGA TGG CAG TAG CTG C-3′, with a product length of 151 bp; VEGF sense strand 5′-CTG TCT TGG GTG CAT TGG A-3′, antisense strand 5′-ATT GGA TGG CAG TAG CTG C-3′, with a product length of 152 bp; β-actin sense strand 5′-CAC CAA CTG GGA CGA CAT-3′, antisense strand 5′-ATC TGG GTC ATC TTC TCG C-3′, with a product length of 138 bp (Shenggong Biotech, Shanghai, China). PCR parameters were as

follows: 95°C for 5 minutes, then 95°C for 30 seconds, 56°C for 30 seconds, 72°C for 40 seconds for 40 cycles. A standard calibration curve for expression of each mRNA was generated using 8-fold dilutions of a control RNA sample. MMP-2 and VEGF mRNA expression Montelukast Sodium was calculated as a ratio to that of β-actin. Immunocytochemistry SW1990 cells and Capan-2 cells were grown on poly-L-lysine-coated slides in a 6-well plate; after treatment with AG490 and IL-6, respectively, the slides of 4 groups were washed twice with PBS and fixed in 4% paraformaldehyde for 30 minutes at room temperature. Immunostaining was performed using the streptavidin-biotin complex method with the UltraSensitive S-P Kit (Fuzhou Maxim Biotech, Fuzhou, China). The slides were pretreated first with 0.3% hydrogen peroxide in PBS for 10 minutes to inactivate endogenous peroxidase, and then microwave antigen retrieval was performed with 0.01 mol/L citrate buffer at pH 6.