Study on the mechanism of quercetin in Sini Decoction Plus Ginseng Soup to inhibit liver cancer and HBV virus replication through CDK1.

BACKGROUND: To explore the anti-tumor and anti-virus key active ingredients of Sini Decoction Plus Ginseng Soup (SNRS) and their mechanisms. METHODS: The main ingredients of SNRS were analyzed by network pharmacology, and quercetin was identified as the key active ingredient. Then, we obtained the targets of quercetin by using Drugbank, PharmMapper, and SwissTargetPrediction databases. Then, the targets of HBV-related hepatocellular carcinoma (HBV-related HCC) were obtained by using Genecards database. In addition, using the gene expression profiles of HBV-related HCC patients in GEO database and the genes with the greatest survival difference in GEPIA 2 database identified the potential targets of quercetin. In addition, the mechanism of potential genes was studied through GO, KEGG analysis, and PPI network. Using AUC and survival analysis to evaluate the diagnostic and prognostic value of cyclin-dependent kinase 1 (CDK1) and CCNB1. Finally, the effects of quercetin on proliferation of Hep3B and HepG2215 cells and the level of CDK1 and CCNB1 were verified in vitro. ELISA was used to measure the expression levels of hepatitis B surface antigen (HBsAg) and hepatitis B e antigen (HBeAg) after the intervention by quercetin for 24 h and 48 h in HepG2215 cell. RESULTS: The first 10 key ingredients of SNRS were identified, and quercetin was the most key ingredient. The 101 potential quercetin targets were identified for the treatment of HBV-related HCC. GO and KEGG showed that 101 potential target enrichment in cancer and cell cycle regulation. By Venn analysis, CDK1 and CCNB1 were intersection targets, which could be used as potential targets for the action of quercetin on HBV-related HCC. Moreover, the expression of CDK1 and CCNB1 was highly expressed in the high-risk group, while the OS rate was low. The 1-year, 3-year and 5-year area under the curve (AUC) curves of CDK1 and CCNB1 were 0.724, 0.676, 0.622 and 0.745, 0.678, 0.634, respectively. Moreover, experimental results also showed that quercetin inhibited cell proliferation and reduced CDK1 expression in Hep3B and HepG2215 cells. The expressions of HBsAg and HBeAg in HepG2215 cell supernatant and cell gradually decreased with the increase of intervention time of quercetin and CDK1 inhibitor. CONCLUSIONS: Quercetin is a key ingredient of anti-HBV-related HCC activity and inhibits HBV replication in SNRS by inhibiting CDK1.

Assessment of cytotoxic and genotoxic potentials of a mononuclear Fe(II) Schiff base complex with photocatalytic activity in Trigonella.

BACKGROUND: In recent times, coordination complexes of iron in various oxidation states along with variety of ligand systems have been designed and developed for effective treatment of cancer cells without adversely affecting the normal cell and tissues of various organs. METHODS: In this study, we have evaluated the mechanism of action of a Fe(II) Schiff base complex in the crop plant Trigonella foenum-graecum L. (Fenugreek) as the screening system by using morphological, cytological, biochemical and molecular approaches. Further functional characterization was performed using MCF-7 cell line and solid tumour model for the assessment of anti-tumour activity of the complex. RESULTS: Our results indicate efficiency of the Fe(II) Schiff base complex in the induction of double strand breaks in DNA. Complex treatment clearly induced cytotoxic and genotoxic damage in Trigonella seedlings. The Fe-complex treatment caused cell cycle arrest via the activation of ATM-ATR kinase mediated DNA damage response pathway with the compromised expression of CDK1, CDK2 and CyclinB1 protein in Trigonella seedlings. In cultured MCF-7 cells, the complex induces cytotoxicity and DNA fragmentation through intracellular ROS generation. Fe-complex treatment inhibited tumour growth in solid tumour model with no additional side effects. CONCLUSION: The growth inhibitory and cytotoxic effects of the complex result from activation of DNA damage response along with oxidative stress and cell cycle arrest. GENERAL SIGNIFICANCE: Overall, our results have provided comprehensive information on the mechanism of action and efficacy of a Fe(II) Schiff base complex in higher eukaryotic genomes and indicated its future implications as potential therapeutic agent.

Marsdenia Tenacissima Extract Inhibits Proliferation and Promotes Apoptosis in Human Ovarian Cancer Cells.

BACKGROUND Marsdenia tenacissima extract (MTE) is a traditional Chinese medicine that can be effectively used against various cancers. However, to the best of our knowledge, its role in ovarian cancer is not known. This study investigated the effects of MTE on human ovarian cancer SKOV3 cells. MATERIAL AND METHODS The viability and cell cycle of SKOV3 cells were assessed using the cell counting kit-8 (CCK-8) and propidium Iodide (PI) staining kit, respectively. Cell apoptosis and mitochondrial membrane potential (MMP) were detected by flow cytometry. The expression levels of proliferation-related and apoptosis-related factors were tested by quantitative real-time PCR (qRT-PCR) and Western blot assays, respectively. RESULTS We found that MTE markedly reduced the viability of SKOV3 cells in dose-dependent and time-dependent manners. MTE induced cell cycle arrest by downregulating the levels of cyclin D1and cyclin B1. MTE (10, 20, and 40 mg/mL) markedly increased apoptosis rates (2.77±0.6%, 4.95±0.97%, and 12.16±0.69%, respectively), and enhanced the loss of MMP. MTE obviously downregulated the expression of B cell lymphoma-2 (Bcl-2) and upregulated the expression levels of fibroblast-associated (Fas), Fas ligand (FasL), cleaved cysteinyl aspartate-specific proteinas-3 (caspase-3), and Bcl-2-associated X protein (Bax) compared to the control group. In addition, the expressions of phosphorylated mammalian target of rapamycin (p-mTOR), phosphorylated protein kinase B (p-AKT), and phosphorylated-phosphatidylinositol 3 kinase (p-PI3K) were decreased by MTE. CONCLUSIONS MTE inhibited proliferation and induced apoptosis of SKOV3 cells. The depression of the PI3K/AKT/mTOR pathway may augment the protective effect of MTE. Thus, MTE might be expected to be a new drug for curing ovarian cancer.

Impaired liver regeneration is associated with reduced cyclin B1 in natural killer T cell-deficient mice.

BACKGROUND: It has been shown that the proportion of natural killer T cells is markedly elevated during liver regeneration and their activation under different conditions can modulate this process. As natural killer T cells and liver injury are central in liver regeneration, elucidating their role is important. METHODS: The aim of the current study is to explore the role of natural killer T cells in impaired liver regeneration. Concanvalin A was injected 4 days before partial hepatectomy to natural killer T cells- deficient mice or to anti CD1d1-treated mice. Ki-67 and proliferating cell nuclear antigen were used to measure hepatocytes proliferation. Expression of hepatic cyclin B1 and proliferating cell nuclear antigen were evaluated by Western Blot and liver injury was assessed by ALT and histology. RESULTS: Natural killer T cells- deficient or mice injected with anti CD1d antibodies exhibited reduced liver regeneration. These mice were considerably resistant to ConA-induced liver injury. In the absence of NKT cells hepatic proliferating cell nuclear antigen and cyclin B1 decreased in mice injected with Concanvalin A before partial hepatectomy. This was accompanied with reduced serum interleukin-6 levels. CONCLUSIONS: Natural killer T cells play an important role in liver regeneration, which is associated with cyclin B1 and interleukin-6.

Carnosic acid induces proteasomal degradation of Cyclin B1, RB and SOX2 along with cell growth arrest and apoptosis in GBM cells.

BACKGROUND: Carnosic acid (CA) is a diterpenoid found in Rosmarinus officinalis L. and Salvia officinalis L. as well as in many other Lamiaceae. This compound is reported to have antioxidant and antimicrobial properties. In addition, a number of reports showed that CA has a cytotoxic activity toward several cancer cell lines. PURPOSE: The aim of this study was to establish whether CA has any specific antiproliferative effect toward human glioblastoma (GBM) cells and to analyze the molecular mechanisms involved. METHODS: We evaluated cell survival by MTT assay, apoptosis and DNA content by flow cytometry, protein expression and phosphorylation by immunoblot analyses. RESULTS: Our results showed that CA inhibited cell survival on both normal astrocytes and GBM cells. In GBM cells, in particular, CA caused an early G2 block, a reduction in the percentage of cells expressing Ki67, an enhanced expression of p21(WAF) and induced apoptosis. Furthermore, we showed that CA promoted proteasomal degradation of several substrate proteins, including Cyclin B1, retinoblastoma (RB), SOX2, and glial fibrillary acid protein (GFAP), whereas MYC levels were not modified. In addition, CA dramatically reduced the activity of CDKs. CONCLUSION: In conclusion, our findings strongly suggest that CA promotes a profound deregulation of cell cycle control and reduces the survival of GBM cells via proteasome-mediated degradation of Cyclin B1, RB and SOX2.

Diallyl disulfide induces G2/M arrest and promotes apoptosis through the p53/p21 and MEK-ERK pathways in human esophageal squamous cell carcinoma.

Esophageal squamous cell carcinoma (ESCC) is an aggressive tumor with high incidence and mortality worldwide. Diallyl disulfide (DADS) is a natural organosulfur compound, isolated from garlic. In this study, MTT assay showed that DADS significantly reduced cell viability in a dose- and time-dependent manner in ESCC cells, with lower toxicity in normal liver cells. Cell cycle analysis revealed that DADS made G2/M phase arrest. Molecular analysis suggested that this cell cycle arrest was likely made by the decrease of cyclin B1, cdc2, p-cdc2, cdc25c in concomitance with activation of the p53/p21 pathway. Apoptosis was detected by Annexin V/PI staining. The molecule markers showed that DADS induced apoptosis through activating caspases, altering the Bax/Bcl-2 balance and suppressing the MEK-ERK pathway. Our data indicated that DADS has the potential to be an effective and safe anticancer agent for ESCC therapy in the near future.

Effect of betulinic acid on the regulation of Hiwi and cyclin B1 in human gastric adenocarcinoma AGS cells.

AIM: To investigate the effect of betulinic acid (BA) on the proliferation, apoptosis and cell cycle of gastric adenocarcinoma cell AGS in vitro and the underlying mechanism. METHODS: The effect of BA on the proliferation of AGS cells was measured by using 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium (MTT) assay. Apoptosis was analyzed by using Annexin V-fluorescein isothiocyanate (FITC)/propidium iodide (PI) double-labeled flow cytometry (FCM) and Hoechst 33258 staining. The influence of BA on cell cycle of AGS cells was tested by PI staining. Both FCM and reverse transcription-PCR (RT-PCR) technologies were applied to detect the expression of Hiwi and Cyclin B1. RESULTS: BA exhibited significant cell proliferation inhibition, as well as its potency of inducing apoptosis in AGS cells in vitro in a time- and dose-dependent manner. The IC(50) value for 24 h was 18.25 microg/mL (95% confidence interval: 15.16 to 27.31 microg/mL). Cells treated with BA showed increased cell population in G(2)/M phase, with decreased S phase population. The expression of Hiwi and Cyclin B1 was down-regulated in BA-treated AGS cells in a dose-dependent manner. CONCLUSION: BA exerted potent effect on growth inhibition, G(2)/M cell cycle arrest and induction of apoptosis in AGS cells in vitro, possibly associated with the down-regulation of Hiwi and its downstream target Cyclin B1 expression. The potent antitumor capacity of BA suggested that it could be a promising new experimental anticancer agent in human gastric adenocarcinoma treatment.

Surfactin induces apoptosis and G(2)/M arrest in human breast cancer MCF-7 cells through cell cycle factor regulation.

Surfactin, purified from Bacillus subtilis natto TK-1, inhibited proliferation of human breast cancer MCF-7 cells in a dose- and time-dependent manner, with IC(50) at 24, 48, and 72 h of 82.6, 27.3, and 14.8 microM, respectively. Surfactin-induced cell death was considered to be apoptotic by observing the typical apoptotic morphological change by acridine orange/ethidium bromide staining and Transferase-mediated dUTP Nick End-labeling assay. [Ca(2+)]i measurement revealed that surfactin induced a sustained increase in concentration of intracellular [Ca(2+)]i. Flow cytometric analysis also demonstrated that surfactin caused time-dependent apoptosis of MCF-7 cells through cell arrest at G(2)/M phase. Western blot revealed that surfactin induced accumulation of the tumor suppressor p53 and cyclin kinase inhibitor p21(waf1/cip1), and inhibited the activity of the G(2)-specific kinase, cyclin B1/p34(cdc2). Based on our findings, surfactin inhibited proliferation in MCF-7 cells by inducing apoptosis and the elevation of [Ca(2+)]i may play an important role in the apoptosis. The mechanism which surfactin caused G(2)/M arrest seems to be through cell cycle factor regulation.