OBJECYIVE To observe the effect of solanine on the contents of caspase-3 and Bcl-2 in HepG2,and to explicate the mechanism by which solanine induces the apoptosis of tumor cells.METHOD Laser confocal scanning microscopy (LCSM) and Western blot are used to measure the contents of caspase-3 and Bcl-2,and LCSM is used to determine their locations in the cell.