Study Of The Inhibition On SGC-7901 Cell Proliferation And The Related Mechanism Of Quercetin

1 Purpose and SignificanceQuercetin is a common dietary antioxidants, as the kind of Polyphenolic flavonoids,the basic physical and chemical properties: soluble in glacial acetic acid,and met an alkaline aqueous solution showing a yellow, almost insoluble in water.About the pharmacological action of quercetin, received wide attention in recent years,such as: anti-bacterial, anti-inflammatory, antitumor, antiviral, immune regulation and protection of cardiovascular function. On anti-tumor, studies have found that quercetin increases cytochrome c reductase, CoenzymeⅡ(NADPH), and Glutathione reductase and DF- lipoamide dehydrogenase activity so as to achieve the pharmacological actions of anticancer. About cancer, prostate cancer, breast cancer,ovarian cancer and so on, however for gastric cancer reports, or deeper mechanism is not clear. This study of quercetin on inhibition of gastric cancer and deep to explore the mechanisms.2 Method2.1 Inhibition of Gastric Cancer Cell Proliferation by QuercetinAbout SGC-7901,combined MTT and crystal violet assay two species experiment method, used 12 h, 18 h, 24 h three time paragraph give cell drug stimulus, MTT get of data draws into table; crystal violet assay experiment aspects, except three groupcrystal violet pictures outside, the hole in the of crystal violet to acetic acid dissolved respectively, determination each hole OD value and draws into figure. Compare study on the inhibition of quercetin on SGC-7901.2.2 Detection of the influence of cell cycle effect of SGC-7901 cells after treated with Quercetin.Guided by the previous studies of MTT and crystal violet assay, filter out the most suitable drug action time, collect cells. By using flow cytometry to Detection of the cell cycle phase distribution of SGC-7901 cells after treated with Quercetin.2.3 Detection of the influence of the expression of related proteins of SGC-7901 cells after treated with Quercetin.To determine the effects of quercetin for block cell cycle about SGC-7901 By flow cytometry, using Western Blotting experiments, testing the expression of protein related protein,such as ATM and p-ATM, H2 AX, and r H2 AX, p-Cdc25 C and Cdc25 C,Chk2, p-Chk2, Cdk2, and p-Cdk2, Cyclin A, which SGC-7901 cells after treated with Quercetin.3 Result3.1 Detection of the inhibition effect of Quercetin on SGC-7901.MTT experiment, To compare the three groups of drugs time, with the increasing concentration of quercetin and its inhibition of both showed a dose-dependent manner.In the experiment of crystal violet assay, with increasing concentration, Crystal Violet absorbance value reduced, the Crystal Violet is also reduced in each hole. Both in terms of Crystal Violet residues on the graph and the measured absorbance value of the corresponding hole in the residue of Crystal Violet, Quercetin has a good inhibitory effect for SGC-7901, but in the human embryonic cells controlled trial found that when 100μM drug concentration, 24 h drug action group had caused massive cell death, thus 18 h duration of action is more appropriate for acting drugs time.3.2 Detection of the influence of the cell cycle phase distribution of SGC-7901 cells after treated with Quercetin.The flow cytometry showed that increased with the dose of quercetin, SGC-7901 rising trend in s phase of the cell cycle, dose-dependent relationship with each other;when the drug at a concentration of 120μM, the percentage of s-phase is reached56.91% than half the percentage, and has significant differences.3.3 Detection of the influence of the expression of related proteins of SGC-7901 cells after treated with Quercetin.In Western Blotting experiment, with the increase of drug concentration, on the related protein expression, its p-ATM, r H2 AX, p-Chk2, p-Cdk2 protein expression with increasing concentration and showing a rising trend, Cdc25 A protein expression levels reduced, whereas Cyclin A remained unchanged.4 Conclusions4.1 The part of inhibition experiments, both the results of MTT, or Crystal Violet assay chart results, quercetin can draw a very good value to SGC-7901, and compare to three groups of drugs time, 18 h drug action time is the best.4.2 by the flow cytometry technology, intuitive concluded that the more number SGC-7901 cells in S phase after treated with Quercetin.4.3 p-ATM, r H2 AX, p-Chk2, p-Cdk2 protein expression amount of rise, Cdc25 A decrease, expression of Cyclin A is essentially the same. Expounds that quercetin through a series of cell cycle related protein phosphorylation plays inhibition efficiency and DNA damage signaling pathways, is likely to be the "ATM-Chk2-Cdc25C-CDK2/Cyclin A" path.