Roles of PLC-γ2 and PKCα in TPA-induced apoptosis of gastric cancer cells

Figure 1 Expression and redistribution of PLC-γ2 in response to TPA. A: Effect of TPA on PLC-γ2 protein expression. Cells were treated with TPA (100 ng/mL) for indicated time, and expression level of PLC-γ2 protein was analyzed by Western blot. α-tubulin was used as a control to quantify the amount of protein used in each lane; B: Translocation of PLC-γ2 in response to TPA. Cells were treated with TPA for indicated time, then immunostained with corresponding antibodies or dye as described in Materials and Methods. The fluorescent images were observed under laser-scanning confocal microscope; C: Redistribution of PLC-γ2 protein in response to TPA. The nuclear and cytosolic fractions were prepared as described in Materials and Methods.

Figure 2 Effect of PLC-γ2 protein expression on apoptosis inducted by TPA. A: Effect of PLC-specific inhibitor U73122 on PLC-γ2 protein expression detected by Western blot. Cells were pretreated with or without U73122 (10^-3 mmol/L) for 3 h, and followed by TPA for indicated time; B: Analysis of apoptotic index. Cells were pretreated with or without U73122 for 3 h, and then exposed to TPA for indicated time. Apoptotic cells were counted among 1000 cells randomly.

Figure 3 Translocation of PKCα protein in the process of apoptosis induced by TPA. A: Redistribution of PKCα protein. Cells were treated with TPA for indicated time, then immunostained with corresponding antibodies or dye as described in Materials and Methods. The images were observed under laser-scanning confocal microscope; B: Effects of various inhibitors, including PKC-specific inhibitor (PIP., 12 μmol/L) and PLC-specific inhibitor (U73122), on redistribution of PKCα. The detecting method was the same as described in Figure 3A; C: Analysis of apoptotic index. The method was similar as in Figure 2B.

Figure 4 Correlation between PLC-γ2 and PKa in their redistribution. A: Effects of PKC- and PLC-specific inhibitors on PLC-γs redistribution. The Method was as described in Figure 3B; B: Effects of PKC- and PLC-specific inhibitors on PKCαexpression detected by Western blot; C: Effects of PKC- and PLC-specific inhibitors on PLC-γ2 expression.