All samples were repeated three times, and data were analyzed by Student’s t test. In vitro clonogenic assay Human lung carcinoma cells were counted after trypsinization. Cells were serially diluted to appropriate concentrations and removed into 25-cm2 flasks in 5-mL medium

in triplicate per data point. After various treatments, cells were maintained for buy GF120918 8 days. Cells were then fixed for 15 minutes with a 3:1 ratio of methanol:acetic acid and stained for 15 minutes with 0.5% crystal violet (Sigma) in methanol. After staining, colonies were counted by the naked eye, with a cutoff of 50 viable cells. Error bars represent ± SE by pooling of the results of three independent experiments. Surviving fraction was calculated as (mean colony counts)/(cells

inoculated)*(plating efficiency), where plating efficiency was defined as mean colony counts/cells inoculated for untreated controls. Cell cycle and apoptosis analysis Flow cytometry analysis of Tariquidar nmr DNA content was performed to assess the cell cycle phase distribution as described previously[6]. Cells were harvested and stained for DNA content using propidium iodide fluorescence. The computer program Multicycle from Phoenix Flow System (San Diego, CA, USA) was used to generate histograms which were used to determine the cell cycle phase distribution and apoptosis. TUNEL staining was also used to detect apoptosis as described previously [7]. The TUNEL stained apoptotic cells were separately numbered in four randomly selected microscopic fields (400*) and graphed. Western blot After various treatments, cells were washed with ice-cold PBS twice before the addition of lysis buffer (20 mM Tris, 150 mM NaCl, 1 mM EDTA, 1% Triton X-100, 2.5 mM sodium NaPPi, 1 mM phenylmethylsulfonyl fluoride, and leupeptin). Protein concentrations were quantified separately by the Bio-Rad SC79 Bradford assay.

Equal amounts of protein were loaded into each well and separated by 10% SDS PAGE, followed by transfer onto nitrocellulose membranes. Membranes were blocked using 5% nonfat dry milk in PBS for 1 hour at room temperature. The Fossariinae blots were then incubated with anti-p21, anti-cyclin D1, anti-bax, anti-bcl-2, anti-clusterin, and anti-caspase-3 antibodies (Santa Cruz Biotechnology, Santa Cruz, CA) at 4°C overnight. Blots were then incubated in secondary antibody conjugated with HRP (1:1000; Santa Cruz Biotechnology) for 1 hour at room temperature. Immunoblots were developed using the enhanced chemiluminescence (ECL) detection system (Amersham, Piscataway, NJ) according to the manufacturer’s protocol and autoradiography. Results As2O3 exerted synergistic effects with DDP on the proliferation of A549 and H460 The MTT assay showed that 10-2 μM to 10 μM inhibited the proliferation of A549 and H460 at 72 hours (Fig. 1). In vitro clonogenic assay proved 10-1 μM to 12.5 μM As2O3 inhibited the proliferation of A549 and H460 cells (Fig. 2). MTT assay results showed that 2.