Resveratrol Enhances Anticancer Effects of Silybin on HepG2 Cells and H22 Tumor-bearing Mice via Inducing G2/M Phase Arrest and Increasing Bax/Bcl-2 Ratio.

BACKGROUND: Silybin, a major flavonoid extracted from the seeds of milk thistle, has a strong hepatoprotective but weak anti-hepatoma activity. Screening another natural ingredient and combining it with silybin is expected to improve the anti-hepatoma efficacy of silybin. OBJECTIVE: The objective of this study was to investigate the synergistic anti-hepatoma effect of resveratrol and silybin on HepG2 cells and H22 tumor-bearing mice in hepatocellular carcinoma (HCC) in vitro and in vivo, respectively. METHODS: Cell viability, scratch wound, clone formation, cell apoptosis, cell cycle, and western blot analysis of HepG2 cells were used to investigate the synergistic effects in vitro of the combination resveratrol with silybin. Growth rates, tumor weights, organ indexes, and histological pathological examination in H22 tumor-bearing mice were used to investigate the synergistic effects in vivo. RESULTS: The combination of resveratrol (50 µg/mL) and silybin (100 µg/mL) significantly suppressed cell viability, whose combination index (CI) was 1.63 (>1.15), indicating the best synergism. The combination exhibited the synergistic effect in blocking the migration and proliferative capacity of HepG2 cells in the measurement in vitro. In particular, resveratrol enhanced the upregulation of Bcl-2 expression and the downregulation of Bax expression with a concurrent increase in the Bax/Bcl-2 ratio. The combination of resveratrol (50 mg/kg) and silybin (100 mg/kg) reduced the tumor weight, inhibited the growth rate, increased the organ indexes, and destroyed the tumor tissue morphology in H22 tumor-bearing mice. CONCLUSION: Resveratrol was found to exhibit synergistic anti-cancer effects with silybin on HepG2 cells and H22 tumor-bearing mice.

[Effect of cigarette smoke extract on RAW264. 7 cell proliferation, autophagy and its mechanism].

OBJECTIVE: To inquiry the effects of cigarette smoke extract(CSE) on RAW264. 7 cell proliferation, autophagy and its mechanism. METHODS: RAW264. 7 cell were used and divided into control, starvation and CSE group(2%, 3%, 4%, 5%CSE). CCK-8 was used to detect the toxic action of CSE on RAW264. 7 cell. Western blot and mRFP-GFP-LC3 cell fluorescence spot count were used to explore the function of CSE on RAW264. 7 cell autophagy and its mechanism. RESULTS: Compared with the control group, the result of CCK-8(0. 671 ± 0. 03、0. 746± 0. 10、0. 584 ± 0. 07、0. 588±0. 05) showed that CSE inhibit the proliferation of RAW 264. 7 cell on 24 hours, the difference was statistically significant(P < 0. 05). The outcomes of Western blot showed that, compared with the control group, LC3 B in the CSE group increased, difference in 6(6. 612 ± 0. 35)/12(4. 383 ± 1. 99)/24(5. 781 ± 0. 78) hours, while P62 decreased in 6(1. 815±0. 08)/12(4. 383±1. 99)/24(0. 414±0. 06) hours also different, P-mTOR(1. 744 ± 0. 15) and P-AKT(0. 376 ± 0. 03) decreased, the difference was statistically significant(P<0. 05), but Beclin1 was not significantly changed. The mRFP-GFP-LC3 cell fluorescence spot count showed that the green fluorescence spot(GFP)decreased and the red fluorescence spot(mRFP) remained stable in CSE group, combined mRFP-GFP is shown as yellow and red spots. CONCLUSION: CSE has toxic effect on cell proliferation and leads to RAW264. 7 cell autophagy enhanced through AKT/m TOR pathways.