Effect of nocodazole on p21 protein levels in transduced cells. (A) Example of a Western blot of whole cell lysate using anti-p21 antibody. (B) Quantitation and statistical analysis of three experiments like that in (A). Data are expressed as the percentage above background density. The mean ± SD is shown. *Statistically significant difference compared with control LXSN cells (P < .05). NOC concentrations were the same as described in Fig 5.