目的 探討紫草素對人結腸癌SW480細胞凋亡和自噬的影響及其機制。方法 取對數生長期人結腸癌SW480細胞，設對照組（DMSO）、紫草素（0.3、0.5、0.7 μg/mL）和LY294002（PI3K特異性抑制劑，5 μg/mL）組。藥物干預48 h后，四甲基偶氮唑鹽（MTT）法檢測SW480細胞增殖抑制率，Annexin V-FITC流式細胞術分析細胞凋亡狀況，蛋白免疫印跡法（Western blotting）檢測p-PI3K、p-Akt、p-mTOR、Caspase-3、cleaved Caspase-3、Bcl-2、Bax、LC3蛋白表達并計算Bax/Bcl-2和LC3-II/LC3-I值。結果 與對照組比較，經紫草素0.3、0.5、0.7 μg/mL或LY294002 5 μg/mL干預能夠顯著提高人結腸癌SW480細胞增殖抑制率和凋亡率（P<0.01）；經紫草素0.5、0.7 μg/mL或LY294002 5 μg/mL干預能夠顯著下調p-PI3K、p-Akt、p-mTOR、Bcl-2蛋白表達，并上調Caspase-3、cleaved Caspase-3、Bax蛋白表達（P<0.05、0.01），提高Bax/Bcl-2和LC3-II/LC3-I值（P<0.01）。與LY294002組比較，經紫草素0.7 μg/mL干預能夠顯著提高SW480細胞增殖抑制率和凋亡率（P<0.05、0.01），下調p-PI3K、p-Akt、p-mTOR蛋白表達并上調Caspase-3、cleaved Caspase-3、Bax蛋白表達（P<0.05、0.01），提高Bax/Bcl-2和LC3-II/LC3-I值（P<0.01）。結論 紫草素能夠促進人結腸癌SW480細胞凋亡和自噬，作用機制可能與抑制PI3K/Akt/mTOR信號通路活化有關。

Objective To investigate the effect and mechanism of shikonin on apoptosis and autophagy of human colon cancer SW480 cells. Methods The human colon cancer SW480 in logarithmic growth phase was treated with DMSO (control group), shikonin (0.3, 0.5, 0.7 μg/mL) and LY294002 (PI3K-specific inhibitor, 5 μg/mL). Totally 48 h after the drugs were given, the proliferation inhibition rate of the SW480 cells was detected by MTT method, the analysis of apoptotic status and calculation of apoptotic rate were detected by Annexin V-FITC staining flow cytometry, the expression of p-PI3K, p-Akt, p-mTOR, Caspase-3, cleaved Caspase-3, Bax, Bcl-2, LC3 proteins were detected by Western blotting, the ratio of Bax/Bcl-2 and LC3-II/LC3-I were calculated. Results Compared with control group, intervented by shikonin 0.3, 0.5, 0.7 μg/mL or LY294002 5 μg/mL could increase SW480 cells proliferation inhibition rate and apoptosis rate (P<0.01); intervented by shikonin 0.5, 0.7 μg/mL or LY294002 5 μg/mL could down-regulate the expression of p-PI3K, p-Akt, p-mTOR and up-regulate the expression of Caspase-3, cleaved Caspase-3, Bax (P<0.05 or 0.01), increase the ratio of Bax/Bcl-2 and LC3-II/LC3-I (P<0.01). Compared with LY294002 5 μg/mL group, intervented by shikonin 0.7 μg/mL could increase SW480 cells proliferation inhibition rate and apoptosis rate (P<0.05 or 0.01); down-regulate the expression of p-PI3K, p-Akt, p-mTOR and up-regulate the expression of Caspase-3, cleaved Caspase-3, Bax (P<0.05 or 0.01); increase the ratio of Bax/Bcl-2 and LC3-II/LC3-I (P<0.01). Conclusions Shikonin can promote apoptosis and autophagy of human colon cancer SW480 cells; which mechanism may be related to inhibiting the activation of PI3K/Akt/mTOR signaling pathway.

R285.5

河北省醫(yī)學科學研究課題計劃（20191801）