MicroRNA-146a通過靶向TAK1誘導(dǎo)胃癌SGC-7901細(xì)胞凋亡*

陳亦明， 周 斌， 王繼生， 徐魯白， 范恒偉， 謝君青

(溫州醫(yī)科大學(xué)附屬第二醫(yī)院肝膽外科， 浙江 溫州 325027)

MicroRNA-146a通過靶向TAK1誘導(dǎo)胃癌SGC-7901細(xì)胞凋亡*

陳亦明△， 周 斌， 王繼生， 徐魯白， 范恒偉， 謝君青

(溫州醫(yī)科大學(xué)附屬第二醫(yī)院肝膽外科， 浙江 溫州 325027)

目的： 觀察微小RNA-146a (miR-146a)對(duì)胃癌SGC-7901細(xì)胞凋亡的影響及其可能的分子機(jī)制。方法: 將miR-146a mimic(上調(diào)miR-146a表達(dá))和miR-146a inhibitor(下調(diào)miR-146a表達(dá))分別轉(zhuǎn)染至人胃癌SGC-7901 細(xì)胞中，同時(shí)設(shè)置miRNA 無義序列轉(zhuǎn)染為陰性對(duì)照組(NC組)。RT-qPCR檢測(cè)轉(zhuǎn)染后胃癌細(xì)胞miR-146a的表達(dá)水平；CCK-8法和流式細(xì)胞術(shù)檢測(cè)miR-146a對(duì)SGC-7901胃癌細(xì)胞生長(zhǎng)活力和凋亡的影響；RT-qPCR和Wes-tern blot法檢測(cè)miR-146a上調(diào)或下調(diào)對(duì)轉(zhuǎn)化生長(zhǎng)因子β激活激酶1(TAK1)/核因子κB (NF-κB)通路的影響。 結(jié)果: 在SGC-7901細(xì)胞中，上調(diào)miR-146a表達(dá)顯著促進(jìn)細(xì)胞凋亡，而下調(diào)miR-146a表達(dá)則顯著抑制細(xì)胞凋亡。與NC組相比，miR-146a mimics轉(zhuǎn)染SGC-7901細(xì)胞后，TAK1的mRNA和蛋白表達(dá)均明顯下降，差異均有統(tǒng)計(jì)學(xué)顯著性(P<0.05)，而miR-146a inhibitors轉(zhuǎn)染組TAK1的mRNA和蛋白質(zhì)表達(dá)則顯著增加(P<0.05)，提示miR-146a負(fù)調(diào)控TAK1表達(dá)。敲低TAK1促進(jìn)SGC-7901細(xì)胞凋亡(P<0.01)，而TAK1過表達(dá)TAKI則抑制SGC-7901細(xì)胞凋亡(P<0.01)。此外，過表達(dá)miR-146a和敲低TAK1均能顯著上調(diào)NF-κB抑制蛋白α(IκBα)和下調(diào)B細(xì)胞淋巴瘤-2(Bcl-2)表達(dá)。結(jié)論: 本研究結(jié)果表明miR-146a通過靶向TAK1抑制NF-κB途徑，從而誘導(dǎo)胃癌細(xì)胞凋亡。

胃癌SGC-7901細(xì)胞； 微小RNA-146a； 轉(zhuǎn)化長(zhǎng)因子β激活激酶1； 核因子κB

研究表明多種基因、酶類和細(xì)胞因子等參與調(diào)控胃癌細(xì)胞活動(dòng)，但迄今胃癌發(fā)生發(fā)展的確切分子機(jī)制仍未完全闡明。微小RNA(microRNA, miR)的表達(dá)在多種腫瘤中會(huì)發(fā)生改變，提示miRNA與腫瘤的發(fā)生發(fā)展密切相關(guān)[1-2]。人類miR-146a基因定位于人染色體5q33。多項(xiàng)研究表明miR-146a參與和腫瘤發(fā)生發(fā)展相關(guān)的多種重要生物學(xué)過程，包括細(xì)胞增殖、分化、凋亡和遷移[3]。目前有證據(jù)表明miR-146a在胃癌中表達(dá)下降，且與腫瘤大小和不良預(yù)后相關(guān)[4]，但其對(duì)胃癌細(xì)胞的調(diào)控機(jī)制尚未完全清楚。

轉(zhuǎn)化生長(zhǎng)因子β激活激酶1(transforming growth factor-β-activated kinase 1，TAK1)是絲裂原活化蛋白激酶(mitogen activated protein kinase，MAPK)家族的成員，能激活核因子κB(nuclear factor-kappa B，NF-κB)通路[5]。在大多數(shù)組織中，TAK1失活會(huì)引起細(xì)胞凋亡[6]。目前有研究表明，miR-146a在乳腺癌組織中抑制NF-κB活性[7]。然而，miR-146a能否通過抑制TAK1表達(dá)從而調(diào)控胃癌細(xì)胞凋亡迄今尚未完全明了。本研究旨在通過上調(diào)和下調(diào)miR-146a表達(dá)，了解其對(duì)胃癌SGC-7901細(xì)胞增殖和凋亡的影響并闡明其可能的分子機(jī)制。

材 料 和 方 法

1 細(xì)胞及試劑

人胃癌SGC-7901細(xì)胞株購(gòu)自上海細(xì)胞生物研究所細(xì)胞庫(kù)；RPMI-1640 細(xì)胞培養(yǎng)基和0.25%含EDTA 的胰酶購(gòu)自HyClone；胎牛血清購(gòu)自Gibco；miR-146a mimic 和miR-146a inhibitor及其無義序列由上海拓然生物科技有限公司合成； TAKI siRNA(siTAK1)由上海吉瑪生物科技有限公司合成構(gòu)建；TAK1-Flag質(zhì)粒購(gòu)自Addgene；Lipofectamine 2000轉(zhuǎn)染試劑購(gòu)自Invitrogen；RT-qPCR試劑盒購(gòu)自TaKaRa；miRNAeasy提取試劑盒購(gòu)自Qiagen；caspase-3試劑盒、抗TAK1抗體、抗NF-κB抑制蛋白α(inhibitor of NF-κB alpha，IκBα)抗體和抗B細(xì)胞淋巴瘤-2(B cell lymphoma 2，Bcl-2)抗體購(gòu)自Cell Signaling Technology；CCK-8試劑盒購(gòu)自Dojindo；Annexin V/PI細(xì)胞凋亡試劑盒購(gòu)自BD Biosciences；所用引物由上海鉑尚生物科技有限公司根據(jù)設(shè)計(jì)合成，見表1。

表1 實(shí)時(shí)熒光定量PCR引物序列

2 主要方法

2.1 細(xì)胞培養(yǎng)和轉(zhuǎn)染 將胃癌SGC-7901細(xì)胞置于含10%胎牛血清、1×105U/L青霉素和100 mg/L鏈霉素的RPMI-1640培養(yǎng)基中，于37 ℃、5% CO2、相對(duì)濕度為95%的培養(yǎng)箱中培養(yǎng)。利用Lipofectamine 2000分別將miR-146a mimic(miR-146a mimic轉(zhuǎn)染組)和miR-146a inhibitor(miR-146a inhibitor轉(zhuǎn)染組)轉(zhuǎn)染至SGC-7901細(xì)胞中48 h，以使miR-146a的表達(dá)上調(diào)或下調(diào)。同時(shí)使用Lipofectamine 2000分別將siTAK1和TAK1-Flag質(zhì)粒轉(zhuǎn)染至SGC-7901細(xì)胞中，使TAK1的表達(dá)下降或升高。轉(zhuǎn)染無義序列或空載體作為陰性對(duì)照(negative control， NC)組。

2.2 RT-qPCR檢測(cè)miRNA和mRNA的表達(dá)水平 按實(shí)驗(yàn)要求將各組轉(zhuǎn)染48 h后的SGC-7901細(xì)胞根據(jù)Trizol試劑說明提取細(xì)胞總RNA；使用miRNAeasy提取試劑盒從SGC-7901細(xì)胞中分離miRNA。使用M-MLV逆轉(zhuǎn)錄酶以總RNA為模版逆轉(zhuǎn)錄成cDNA。應(yīng)用Oligo(dT)18作為逆轉(zhuǎn)錄的引物。以U6和GAPDH為內(nèi)參照，2-ΔΔCt方法計(jì)算miRNA和mRNA的相對(duì)表達(dá)水平。

2.3 流式細(xì)胞術(shù)檢測(cè)細(xì)胞凋亡率 收集各組轉(zhuǎn)染48 h后的SGC-7901細(xì)胞，并以1×109/L的濃度將細(xì)胞重懸于PBS液，5 μL Annexin V和5 μL PI室溫避光孵育15 min后，使用Accurri C6流式細(xì)胞儀檢測(cè)各組細(xì)胞凋亡情況，檢測(cè)結(jié)果使用FlowJo 7.6.2軟件進(jìn)行分析。

2.4 測(cè)定caspase-3活性 將轉(zhuǎn)染后的SGC-7901細(xì)胞接種在96孔板中培養(yǎng)48 h，然后根據(jù)caspase-3試劑盒說明書進(jìn)行處理。孵育后的樣品板放入VeritasTM發(fā)光檢測(cè)儀中，檢測(cè)每個(gè)樣品的熒光值，進(jìn)行數(shù)據(jù)分析。

2.5 CCK-8法檢測(cè)細(xì)胞活力 將轉(zhuǎn)染后的SGC-7901細(xì)胞以每孔4 000個(gè)的密度接種于96孔板中，每孔加含10% 胎牛血清的RPMI-1640培養(yǎng)基，每6 孔為1 組，分別于接種后1 d、2 d和3 d每孔加入CCK-8 試劑10 μL，置37 ℃、5% CO2培養(yǎng)箱中孵育2 h，在450 nm波長(zhǎng)處檢測(cè)吸光度(A)值。取每天6孔平均值繪制細(xì)胞生長(zhǎng)曲線。

2.6 Western blot法檢測(cè)蛋白表達(dá) 收集SGC-7901細(xì)胞并用裂解液(0.5% NP40)提取總蛋白，BCA試劑盒檢測(cè)細(xì)胞中總蛋白濃度。各組上樣30 μg總蛋白，10% SDS-PAGE分離蛋白質(zhì)后轉(zhuǎn)至硝酸纖維素膜，膜在5%脫脂牛奶中(室溫)封閉1 h，分別加入TAK1(1∶1 000)、IκBα(1∶1 000)和Bcl-2(1∶1 000)I抗4 ℃下孵育過夜；TBST洗滌膜 10 min，3次；然后，將膜浸泡于相對(duì)應(yīng)的II抗中，在室溫下孵育2 h，再次清洗后化學(xué)發(fā)光顯影。用ImageJ圖像分析軟件對(duì)目的條帶灰度值進(jìn)行定量分析，計(jì)算TAK1、IκBα和Bcl-2與β-actin的灰度值比值，得到其相對(duì)表達(dá)量。

3 統(tǒng)計(jì)學(xué)處理

所有數(shù)據(jù)采用SPSS 19.0統(tǒng)計(jì)軟件進(jìn)行分析。各組數(shù)據(jù)以均數(shù)±標(biāo)準(zhǔn)差(Mean±SD)表示，兩組間數(shù)據(jù)比較采用t檢驗(yàn)，多組間數(shù)據(jù)比較采用單因素方差(one-way ANOVA)分析。以P<0.05為差異有統(tǒng)計(jì)學(xué)意義。

結(jié) 果

1 調(diào)控miR-146a表達(dá)對(duì)胃癌SGC-7901細(xì)胞凋亡的影響

RT-qPCR檢測(cè)發(fā)現(xiàn)miR-146a mimic 轉(zhuǎn)染SGC-7901細(xì)胞48 h后，miR-146a的表達(dá)上調(diào)，比對(duì)照組增加近3.8倍；而轉(zhuǎn)染miR-146a inhibitor后，miR-146a表達(dá)水平下降至對(duì)照組的10%左右；說明miR-146a mimic和miR-146a inhibitor轉(zhuǎn)染SGC-7901細(xì)胞成功。流式細(xì)胞術(shù)檢測(cè)發(fā)現(xiàn)miR-146a mimic轉(zhuǎn)染組的SGC-7901細(xì)胞凋亡率明顯高于對(duì)照組(P<0.05)；而miR-146a inhibitor轉(zhuǎn)染后細(xì)胞凋亡率顯著下降(P<0.05)。此外，通過caspase-3活性來評(píng)估m(xù)iR-146a對(duì)SGC-7901凋亡的影響， 上調(diào)miR-146a表達(dá)顯著增加caspase-3活性，而下調(diào)miR-146a表達(dá)則抑制caspase-3活性，差異均有統(tǒng)計(jì)學(xué)顯著性(P<0.01)，見圖1、2、3。

Figure 1.The expression of miR-146a in the SGC-7901 cells transfected with miR-146a mimic or miR-146a inhibitor. Mean±SD.n=3.**P<0.01vsNC group.

圖1 miR-146a mimic或miR-146a inhibitors轉(zhuǎn)染SGC-7901細(xì)胞后miR-146a的表達(dá)情況

Figure 2.The effect of regulating miR-146a mimic and miR-146a inhibitor on the apoptosis of SGC-7901 cells. Mean±SD.n=6.*P<0.05vsNC group.

圖2 調(diào)控miR-146a表達(dá)對(duì)SGC-7901細(xì)胞凋亡的影響

Figure 3.The effect of miR-146a mimic and miR-146a inhibitor on the caspase-3 activity in the SGC-7901 cells. Mean±SD.n=6.**P<0.01vsNC group．

圖3 調(diào)控miR-146a表達(dá)對(duì)SGC-7901細(xì)胞caspase-3活性的影響

2 調(diào)控miR-146a表達(dá)對(duì)SGC-7901細(xì)胞生長(zhǎng)活力的影響

CCK-8實(shí)驗(yàn)發(fā)現(xiàn)miR-146a mimic轉(zhuǎn)染SGC-7901細(xì)胞后1 d、2 d和3 d，SGC-7901細(xì)胞生長(zhǎng)活力均顯著低于對(duì)照組(P<0.05)；而轉(zhuǎn)染miR-146a inhibitor后1 d、2 d和3 d，SGC-7901細(xì)胞生長(zhǎng)活力均顯著高于對(duì)照組(P<0.01)，見圖4。

3 調(diào)控miR-146a表達(dá)對(duì)TAK1表達(dá)的影響

與對(duì)照組相比，miR-146a mimic轉(zhuǎn)染SGC-7901細(xì)胞后，TAK1的mRNA和蛋白表達(dá)水平均明顯下降，差異均有統(tǒng)計(jì)學(xué)顯著性(P<0.05)；而miR-146a inhibitor轉(zhuǎn)染SGC-7901細(xì)胞后，TAK1的mRNA和蛋白質(zhì)表達(dá)水平較對(duì)照組顯著增加(P<0.05)，見圖5。

Figure 4.The effect of miR-146a mimic and miR-146a inhibitor on the cell activity of SGC-7901 cells. Mean±SD.n=6.*P<0.05,**P<0.01vsNC group.

圖4 調(diào)控miR-146a表達(dá)對(duì)SGC-7901細(xì)胞活力的影響

Figure 5.The effect of miR-146a mimic and miR-146a inhibitor on the expression of TAK1 at mRNA and protein levels in the SGC-7901 cells. TAK1 expression in the SGC-7901 cells transfected with miR-146a mimic was analyzed by RT-qPCR (A) and Western blot (B). TAK1 expression in SGC-7901 cells transfected with miR-146a inhibitor was analyzed by RT-qPCR (C) and Western blot (D). Mean±SD.n=3.*P<0.05,**P<0.01vsNC group.

圖5 調(diào)控miR-146a表達(dá)對(duì)SGC-7901細(xì)胞TAK1 mRNA和蛋白表達(dá)的影響

4 調(diào)控TAK1表達(dá)對(duì)SGC-7901細(xì)胞凋亡的影響

本研究通過siTAK1和TAK1-Flag調(diào)節(jié)TAK1表達(dá)，觀察TAK1對(duì)胃癌細(xì)胞的影響。轉(zhuǎn)染 siTAK1后，SGC-7901細(xì)胞TAK1的mRNA表達(dá)水平降至對(duì)照組的15.0% 左右，說明siTAK1成功轉(zhuǎn)染SGC-7901細(xì)胞。流式細(xì)胞術(shù)結(jié)果顯示，siTAK1轉(zhuǎn)染后，SGC-7901細(xì)胞凋亡率較對(duì)照組顯著增加(P<0.01)。反之，TAK1-Flag轉(zhuǎn)染SGC-7901細(xì)胞使TAK1蛋白過表達(dá)后，SGC-7901細(xì)胞凋亡率顯著減少(P<0.01)，見圖6、7、8。

Figure 6.The mRNA expression of TAK1 in the SGC-7901 cells transfected with siTAK1. Mean±SD.n=3.**P<0.01vsNC group.

圖6 SGC-7901細(xì)胞轉(zhuǎn)染siTAK1后TAK1的mRNA表達(dá)變化

Figure 7.The effect of siTAK1 on the apoptosis of SGC-7901 cells was detected by flow cytometry with FITC-Annexin V and PI staining. Mean±SD.n=6.*P<0.05vsNC group.

圖7 下調(diào)TAK1表達(dá)對(duì)SGC-7901細(xì)胞凋亡的影響

Figure 8.The effect of TAK1-Flag on the apoptotic rate of SGC-7901 cells was detected by flow cytometry with FITC-Annexin V and PI staining. Mean±SD.n=6.*P<0.05vsNC group.

圖8 過表達(dá)TAK1對(duì)SGC-7901細(xì)胞凋亡的影響

5 調(diào)控miR-146a表達(dá)對(duì)NF-κB途徑的影響

Western blot結(jié)果顯示，轉(zhuǎn)染miR-146a mimic后的SGC-7901細(xì)胞，其IκBα蛋白水平為對(duì)照組的2.1倍；相反的，轉(zhuǎn)染miR-146a inhibitor后，IκBα蛋白水平降至對(duì)照組的66.1%。與此同時(shí)，通過siTAK1 抑制TAK1表達(dá)后，IκBα的蛋白水平增加(為對(duì)照組的1.5倍)；而TAK1過表達(dá)后，IκBα降至對(duì)照組的62.0%。此外，本研究還檢測(cè)了miR-146a和TAK1對(duì)Bcl-2表達(dá)的影響。miR-146a mimic轉(zhuǎn)染SGC-7901細(xì)胞后，Bcl-2表達(dá)下降(P<0.05)，而miR-146a inhibitor轉(zhuǎn)染后，胃癌細(xì)胞Bcl-2表達(dá)增加(P<0.05)。siTAK1轉(zhuǎn)染SGC-7901細(xì)胞后，Bcl-2表達(dá)下降(P<0.05)，而TAK1過表達(dá)時(shí)，胃癌細(xì)胞Bcl-2表達(dá)增加(P<0.05)，見圖9。

討 論

miR-146a是miRNA大家族的重要一員，既往研究發(fā)現(xiàn)miR-146a在乳腺癌和前列腺癌等惡性腫瘤中發(fā)揮抑癌作用[7-8]。Kogo等[4]和Hou等[9]均發(fā)現(xiàn)miR-146a在胃癌組織中表達(dá)減少；Kogo等[4]發(fā)現(xiàn)miR-146a的低表達(dá)與胃癌的淋巴結(jié)轉(zhuǎn)移和血行轉(zhuǎn)移有關(guān)；Hou等[9]發(fā)現(xiàn)，miR-146a能抑制胃癌MKN-45細(xì)胞的存活并促進(jìn)其凋亡。此外，還有研究表明miR-146a能抑制胃癌的轉(zhuǎn)移[10]。這些都提示miR-146a在胃癌中發(fā)揮抑癌作用。本研究發(fā)現(xiàn)經(jīng)miR-146a mimic和miR-146a inhibitor轉(zhuǎn)染后，過表達(dá)miR-146a可以促進(jìn)SGC-7901細(xì)胞凋亡并抑制其增殖，而下調(diào)miR-146a可以促進(jìn)SGC-7901細(xì)胞增殖并抑制其凋亡，這些結(jié)果提示miR-146a在胃癌的發(fā)生過程中發(fā)揮著抑癌作用。

Figure 9.The effect of miR-146a mimic (A)， miR-146a inhibitor (B)， siTAK1 (C) and TAK1-Flag (D) on the protein expression of IκBα and Bcl-2 in the SGC-7901 cells. Mean±SD.n=3.*P<0.05,**P<0.01vsNC group.

圖9 miR-146a和TAK1調(diào)控表達(dá)對(duì)SGC-7901細(xì)胞IκBα和Bcl-2蛋白表達(dá)的影響

在胃癌細(xì)胞中，NF-κB通路在調(diào)節(jié)細(xì)胞生存、凋亡和炎癥中起關(guān)鍵作用，NF-κB活化與胃癌的不良結(jié)局相關(guān)[11]。bcl-2基因是NF-κB的直接靶點(diǎn)，與IκBα形成負(fù)反饋環(huán)路。最近研究表明，在乳腺癌細(xì)胞中過表達(dá)miR-146a可減少IκBα的磷酸化[7]。在非小細(xì)胞肺癌細(xì)胞中miR-146a過表達(dá)會(huì)引起IκBα表達(dá)的上調(diào)[12]。本研究發(fā)現(xiàn)miR-146a過表達(dá)顯著增加了胃癌細(xì)胞的IκBα表達(dá)，對(duì)Bcl-2表達(dá)起抑制作用；而miR-146a下調(diào)降低了IκBα的水平，上調(diào)了Bcl-2的表達(dá)。因此，本研究表明miR-146a通過上調(diào)IκBα的表達(dá)而抑制NF-κB途徑誘導(dǎo)SGC-7901細(xì)胞凋亡。

TAK1是NF-κB的上游激酶，被稱為決定細(xì)胞命運(yùn)的關(guān)鍵分子成分。研究表明TAK1通過磷酸化IκB激酶復(fù)合物使其降解和釋放NF-κB，NF-κB遷移至細(xì)胞核后轉(zhuǎn)變?yōu)榛钚孕问剑缓蠹せ钜幌盗袇⑴c抑制凋亡和促進(jìn)增殖的基因[5-6]。本研究發(fā)現(xiàn)miR-146a反向調(diào)控TAK1的表達(dá)。此外，過表達(dá)miR-146a或敲低TAK1均導(dǎo)致SGC-7901細(xì)胞IκBα表達(dá)增加。相反，下調(diào)miR-146a或過表達(dá)TAK1可下調(diào)IkBα的蛋白水平。因此，miR-146a可能是通過負(fù)調(diào)控胃癌細(xì)胞TAK1表達(dá)而抑制NF-κB途徑。

綜上所述，本研究通過調(diào)節(jié)miR-146a表達(dá)觀察其對(duì)胃癌SGC-7901 細(xì)胞生長(zhǎng)和凋亡的影響，并表明miR-146a可能通過靶向TAK1抑制NF-κB途徑誘導(dǎo)胃癌細(xì)胞凋亡。

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(責(zé)任編輯： 林白霜， 余小慧)

MicroRNA-146a promotes apoptosis of gastric cancer SGC-7901 cells by targeting TAK1

CHEN Yi-ming, ZHOU Bin, WANG Ji-sheng, XU Lu-bai, FAN Heng-wei, XIE Jun-qing

(DepartmentofHepatobiliarySurgery,TheSecondAffiliatedHospital,WenzhouMedicalUniversity,Wenzhou325027,China.E-mail:chenyiming209 @126.com)

AIM: To explore the effect of microRNA-146a (miR-146a) on apoptosis of human gastric cancer SGC-7901 cells and the underluing mechanism. METHODS: miR-146a mimic (up-regulated miR-146a expression) and miR-146a inhibitor (down-regulated miR-146a expression) were transfected into the SGC-7901 cells by liposome method. At the same time, miRNA nonsense sequence transfection group as the negative control group (NC group) was set up. RT-qPCR was used to evaluate the levels of miR-146a in the SGC-7901 cells after transfection. The effects of miR-146a on the cell apoptosis and growth were assessed by flow cytometry analysis and CCK-8 assay， respectively. The effect of over-expression or knockdown of miR-146a on transforming growth factor-β-activated kinase 1 (TAK1)/ nuclear factor-kappa B (NF-κB) signaling was evaluated by RT-qPCR and Western blot. RESULTS: miR-146a modulated apoptosis of SGC-7901 cells. Over-expression of miR-146a significantly increased apoptosis, whereas knockdown of miR-146a inhibited the apoptosis of SGC-7901 cells. The expression of TAK1 at mRNA and protein levels was significantly decreased when miR-146a mimic was transfected into the SGC-7901 cells (P<0.05). On the contrast, the expression of TAK1 at mRNA and protein were significantly higher in miR-146a inhibitor transfection group than that in NC group (P<0.05), suggesting that miR-146a negatively regulated TAK1 expression. Moreover, knockdown of TAK1 enhanced the apoptosis of SGC-7901 cells (P<0.01), while over-expression of TAK1 inhibited the apoptosis of SGC-7901 cells(P<0.01). Additionally, both over-expression of miR-146a and knockdown of TAK1 led to a prominent increase in the expression of NF-κB inhibitor protein alpha (IκBα) and a significat decrease in B cell lymphoma-2 (Bcl-2) level in the SGC-7901 cells. CONCLUSION: miR-146a significantly promotes apoptosis of SGC-7901 cells by inhibition of NF-κB pathway via targeting TAK1.

Gastric cancer SGC-7901 cells; MicroRNA-146a; Transforming growth factor-β-activated kinase 1; Nuclear factor-kappa B

1000- 4718(2017)08- 1436- 07

2016- 12- 19

2017- 07- 06

溫州市科技計(jì)劃項(xiàng)目(No. Y20130231)

R730.23

A

10.3969/j.issn.1000- 4718.2017.08.015

雜志網(wǎng)址： http://www.cjpp.net

△通訊作者 Tel: 0577-88002710; E-mail: chenyiming209@126.com