c-Myc down-regulation precedes the U0126-mediated effects on G0/G1 arrest and cell cycle proteins expression. A. Histogram showing the number of RD cells in G0/G1 phase expressed as percentage (black bars) and c-Myc levels (grey bars) expressed as arbitrary units (density of c-Myc band/α-tubulin band) in untreated (-) and U0126-treated RD cells (+) for the indicated times. Similar results were obtained in two separate experiments B. Cell lysates from RD cells untreated (-) or treated (+) with U0126 for indicated times were analysed by immuoblotting with specific antibodies for indicated proteins. α-tubulin expression shows the loading of samples. The values of fold increases over the controls, arbitrarly set at 1, are obtained by densitometric analysis (lower panel). Similar results were obtained in three different experiments.