CS-6 inhibited cell viability and changed morphology. (A) Chemical structure of CS-6. (B, C) Human lung cancer A549, H1299, H322 cells and human embryo lung fibroblast (HLF) cells were treated with CS-6 under normal culture medium at the indicated doses. (B) The changes in cell morphology and spreading in A549 cells treated with CS-6 for 48 h were observed and cells were photographed using a microscope fitted with digital camera. (C) At 48 hours after treatment, the cell viability was determined by a MTT assay. The data are presented as mean ± SD of three tests. (*P < 0.05,**P < 0.01, significant differences between CS-6treatment groups and DMSO vehicle control groups).