ABSTRACT
Background and purpose:Tetrandrine is a natural compound whose role in retinoblastoma remains unclear. This study investigated the effects of tetrandrine (Tet) on human retinoblastoma cells.Methods:CCK-8 assays were performed to analyze the effects of Tet on viability of retinoblastoma cells. The apoptosis rate was determined by Annexin V/PI assays. After staining with 2′,7′-dichlorolfuorescin diacetate (DCFH-DA), cellular reactive oxygen species (ROS) was measured by lfow cytometry. Akt and p-Akt were detected by Western blot.Results:Tet inhibited cell viability of retinoblastoma cells. After treatment with Tet (4, 8, 10 and 20μmol/L) for 24h, cell viability inhibition rates of WERI-Rb-I were 5.7%, 25.0%, 55.1% and 84.9%, whereas inhibition rates of Y79 cells were 2.4%,2.9%, 23.8% and 54.2% (P<0.01). In cells treated with 10μmol/L of Tet for 12, 24 and 48 h, cell viability inhibition rates of WERI-Rb-I were 6.0%, 45.5% and 74.7%, whereas inhibition rates of Y79 cells were 2.9%, 19.4% and 43.3% (P<0.01). Tet induced retinoblastoma cell apoptosis. After treatment with Tet (10 μmol/L) for 24 and 48 h, apoptosis rates of WERI-Rb-I were (23.70±1.75)% and (34.83±3.15)%, respectively, whereas apoptosis rates of Y79 cells were (9.62±2.69)% and (14.97±1.50)%, respectively (P<0.01). Apoptosis inhibitor Z-VAD-FMK attenuated Tet-induced cell death (P<0.05). ROS levels were indeed increased in cells treated with Tet (10 μmol/L) for 6 and 12 h (P<0.01), while N-Acetyl-L-cysteine (NAC) decreased Tet-induced ROS (P<0.01). After ROS was inhibited by NAC, apoptosis rate was decreased compared with the control (P<0.01). Further study indicated that Tet inhibited PI3K/Akt pathway in retinoblastoma cells.Conclusion:Tet induces cell apoptosis via increasing ROS synthesis and inhibiting PI3K/Akt pathway.
ABSTRACT
Background and purpose:Pterostilbene is a natural antioxidant, whose role in retinoblastoma remains unclear. The aim of this study is to probe the effects of pterostilbene on the proliferation, apoptosis and autophagy in retinoblastoma WERI-Rb-1 cell lines.Methods:Cell counting kit-8 (CCK-8) assays were used to analyze the effects of pterostilbene on the proliferation of WERI-Rb-1 cells. Apoptosis rate was determined by Annexin V/PI. Autophagic vacuoles were observed by acridine orange staining. LC3 and P62 protein expressions were determined using Western blot.Results:Pterostilbene significantly inhibited the proliferation of WERI-Rb-1 cells (P<0.01). The cell viability were (93.02±0.47)%, (55.10±2.04)% and (30.33±1.45)% after WERI-Rb-1 cells were treated with 25, 50 and 100 μmol/L pterostilbene for 24 h, and the cell viability were (88.38±3.70)%, (53.37±1.17)%, (29.60±1.05)% after WERI-Rb-1 cells were treated with 50 μmol/L pterostilbene for 12, 24 and 48 h. Pterostilbene induced cell apoptosis (P<0.01), the apoptosis rates of control group, 24 h treated group and 48 h treated group were (4.08±0.79)%, (13.44±2.12)% and (23.49±2.01)%. Pterostilbene induced autophagy of WERI-Rb-1 cells, increased LC3 expression, downregulated P62 expression and increased the number of autophagic vacuoles in WERI-Rb-1 cells (P<0.01). 3-MA and Beclin1 were able to rescue pterostilbene-induced cell death (P<0.01). After 3-MA was used to blunt autophagosome formation, the apoptosis rate markedly decreased in 3-MA+pterostilbene-treated cells compared with cells treated with pterostilbene alone [(12.97±2.09)%vs (8.35±1.11)%], and after siRNA was used to knockdown Beclin1, the apoptosis rate had the same change [(13.80±2.19)%vs (9.62±0.52)%].Conclusion:Pterostilbene can inhibit the proliferation of WERI-Rb-1 cells and induce cell apoptosis via autophagy activation.
ABSTRACT
Objective To study the effect of spider venom from Macrothele raveni on proliferation and cell cycles of human hepatocellular carcinoma cell line SMMC-7721 and the molecular mechanism of the(effect.) Methods Proliferation of SMMC-7721 cells was determined by MTT assay.DNA synthesis of SMMC-7721 cell pre-and post-treatment with spider venom from M.raveni was tested by -TdR(assay.) The induction of apoptosis and the change of cell cycle in SMMC-7721 cells treated with spider(venom) from M.raveni were investigated by Flow Cytometry.The effect of spider venom from M.raveni on expression of c-myc protein in SMMC-7721 cells was studied by Western Blot.Results MTT assay showed that the proliferation of SMMC-7721 cells in vitro was inhibited by spider venom from M.raveni((P