Effect of sulforaphane on protein expression by proteomics analysis. (A) Representative silver nitrate staining pattern in SFN (80 μM) treated LNCaP cells. Proteins (200 μg) were separated on pH 4-10 nonlinear IPG strip in the first dimension and 12% homogenous SDS-PAGE in the second dimension. Staining was performed with alkaline silver. (B) Gel image regions of SFN-treated group and untreated control with differentially expressed protein spots identified by Ettan MALDI-TOF analysis.