Analysis of cyclin D1 expression in SH-SY5Y treated with SI 34. (A) Immunoblot of SH-SY5Y cells exposed to 10 μM SI 34 for 6-72 hours: a representative of three separate experiments is shown. (B) Quantification of cyclin D1 expression from blots in panels A achieved with ImageJ software. Histogram shows the results of the densitometric analysis of autoradiographic bands in which the protein levels were normalized for β-actin (black bars for the untreated cultures and white bars for the cells exposed to SI 34 10 μM for the indicated times). Levels are extrapolated as percentages of the values detected in control cells, which are arbitrarily assigned as 100%.