Figure 6. Effect of M3 or ChAT siRNA transfection on the growth of H1299 cells.

Down-regulation of M3 and ChAT protein was detected by western blot 72 h post transfection of 200 nM siRNAs (A and B). Cells were incubated in the presence of 200 nM siRNA for 48, 72 and 96 h, after that, cell growth viability was determined using the SRB assay and compared with the mock control. ^** P<0.01, ^*** P<0.001, compared with the negative control siRNA transfected cells at the same time point (C). Following M3 or Negative siRNA transfection, cells were treated with or without R2HBJJ (8 µM and 16 µM) for 72 h and the combination effect of M3 siRNA knockdown and R2HBJJ treatment on cell growth was investigated using the SRB assay. ^# P<0.05, ^## P<0.01, compared with the negative siRNA transfected cells treated with solvent. (D). Each data point represents the means ± SD of three independent experiments.