Pterostilbene induces retinoblastoma WERI-Rb-1 cell apoptosis via autophagy induction / 中国癌症杂志

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.

Tetrandrine induces retinoblastoma cells apoptosis via ROS induction and PI3K/Akt inhibition / 中国癌症杂志

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.

Effect of spider venom from Macrothele raveni on proliferation and cell cycle of human hepatocellular carcinoma cell line SMMC-7721 / 中草药

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