Objective: To explore the effects of stromal interaction molecule 1 (STIM1) on the expression of apoptosis-related proteins in prostate cancer PC-3 cells.
Methods: We transfected the lentivirus vector STIM1-pGCSIL-GFP carrying STIM shRNA into human hormone-independent prostate cancer PC-3 cells, and 3 days later observed the transfection efficiency by fluorescence microscopy. At 7 days after transfection, we determined the expression of STIM1 in the PC-3 cells by RT-PCR and Western blot and those of apoptosis-related proteins Bcl-2, Bax, survivin and activated Caspase-3 by Western blot.
Results: At 3 days, inverted microscopy revealed a transfection efficiency of > 80%. At 7 days, the STIM1 expression was significantly inhibited at both mRNA and protein levels. The Bcl-2/Bax rate was remarkably decreased as compared with that of the control group (0. 31 vs 1.24 ) , and the survivin expression was markedly reduced, 0. 14 times that of the relative expression in the control. However, the Caspase-3 cleavage was significantly activated, 1.52 times that of the control (P <0.05).
Conclusion: STIM1 can be regarded as an oncogene in prostate cancer PC-3 cells. Inhibition of its expression can induce PC-3 cell apoptosis by reducing the Bcl-2/Bax rate, decreasing the survivin expression, and activating the Caspase-3 pathway.