孫菊萍姜?jiǎng)P
雷公藤紅素逆轉(zhuǎn)宮頸癌細(xì)胞順鉑耐藥性實(shí)驗(yàn)研究
孫菊萍1姜?jiǎng)P2
目的研究中藥活性成分雷公藤紅素逆轉(zhuǎn)耐藥宮頸癌細(xì)胞株Hela/R對(duì)順鉑的耐藥性,并探討其機(jī)制。方法采用順鉑梯度暴露法構(gòu)建順鉑耐藥宮頸癌細(xì)胞株Hela/R;采用MTT法檢測(cè)雷公藤紅素是否能增強(qiáng)順鉑對(duì)Hela/R的殺傷活性;Western blot試驗(yàn)檢測(cè)常規(guī)Hela細(xì)胞及Hela/R細(xì)胞抗凋亡蛋白Bcl-2、Bcl-w及Bcl-xl表達(dá)水平;流式細(xì)胞術(shù)檢測(cè)雷公藤紅素聯(lián)合順鉑對(duì)Hela/R細(xì)胞的凋亡誘導(dǎo)效應(yīng)及對(duì)線粒體膜電位的影響。結(jié)果1、2、4、8、16、32、64μmol/L順鉑對(duì)Hela及Hela/R細(xì)胞的細(xì)胞活力抑制率分別為:(18.6±1.5)%(Hela),(1.9±1.0)%(Hela/R);(23.9±2.4)%(Hela),(3.1±1.2)%(Hela/R);(47.8±3.9)%(Hela),(6.8±1.5)%(Hela/R);(63.4±5.4)%(Hela),(11.6±1.8)%(Hela/R);(72.7±5.9)%(Hela),(20.4±2.0)%(Hela/R),(85.7±6.7)%(Hela),(41.2± 3.3)%(Hela/R);(91.8±7.9)%(Hela),(55.8±4.3)%(Hela/R),兩組比較,P均<0.05。2μmol/L雷公藤紅素對(duì)Hela/R細(xì)胞的細(xì)胞活力抑制率為(6.6±1.1)%;2μmol/L雷公藤紅素分別加10、20、40μmol/L順鉑組Hela/R細(xì)胞的細(xì)胞活力抑制率優(yōu)于單用10、20、40μmol/L順鉑組[(57.2±3.9)%比(12.4± 1.2)%、(71.4±5.1)%比(27.8±1.9)%、(84.8±6.8)%比(45.2±3.1)%,P<0.05]。Hela/R細(xì)胞Bcl-w/βactin表達(dá)水平高于Hela細(xì)胞[(70.9±4.9)比(22.1±1.3),P<0.05],Bcl-2/β-actin與Bcl-xl/β-actin表達(dá)水平差異無(wú)統(tǒng)計(jì)學(xué)意義(P>0.05)。與對(duì)照組比較,雷公藤紅素可明顯抑制Hela/R細(xì)胞Bcl-w/βactin的表達(dá)[(29.3±2.6)比(68.9±4.5),P<0.05]。雷公藤紅素增強(qiáng)順鉑對(duì)Hela/R細(xì)胞線粒體膜電位的損傷,促進(jìn)細(xì)胞色素C的釋放,而誘導(dǎo)Hela/R細(xì)胞發(fā)生凋亡。結(jié)論雷公藤紅素體外能提高順鉑對(duì)耐藥宮頸癌細(xì)胞的殺傷活性,其機(jī)制可能為通過(guò)抑制Bcl-w表達(dá),提高促凋亡蛋白的活性,進(jìn)而促進(jìn)耐藥宮頸癌細(xì)胞發(fā)生線粒體途徑的凋亡。
耐藥宮頸癌細(xì)胞株;順鉑;Hela/R;雷公藤紅素;Bcl-w;線粒體;凋亡
宮頸癌是全球發(fā)病率第二位的婦科腫瘤,每年有超過(guò)50萬(wàn)患者被診斷為宮頸癌,化療目前仍是治療宮頸癌的主要手段[1]。順鉑是治療多種實(shí)體瘤的一線藥物,它能損傷腫瘤細(xì)胞的DNA進(jìn)而誘導(dǎo)細(xì)胞進(jìn)入凋亡程序[2]。然而,順鉑的反復(fù)使用常常誘導(dǎo)腫瘤細(xì)胞產(chǎn)生耐藥性,抵抗順鉑誘導(dǎo)的凋亡效應(yīng)[3]。因此,尋找其他的藥物與順鉑進(jìn)行聯(lián)合用藥以延緩順鉑的耐藥性是目前腫瘤治療研究的重點(diǎn)。本研究的目的在于探討中藥活性成分雷公藤紅素是否能逆轉(zhuǎn)耐藥宮頸癌細(xì)胞株Hela/R對(duì)順鉑的耐藥性并研究其具體機(jī)制。
1.1 細(xì)胞培養(yǎng)與Hela/R的構(gòu)建人宮頸癌細(xì)胞系Hela購(gòu)于美國(guó)ATCC(American Type Culture Collection),腫瘤細(xì)胞培養(yǎng)在RPMI-1640培養(yǎng)基中,含10%胎牛血清,培養(yǎng)環(huán)境為37℃恒溫且通入5%的CO2。順鉑耐藥Hela(Hela/R)細(xì)胞的構(gòu)建采用順鉑梯度暴露法[4]:將Hela細(xì)胞用一個(gè)濃度的順鉑處理48h,之后將其移至無(wú)順鉑培養(yǎng)基培養(yǎng)48h,重復(fù)3次后將細(xì)胞移至更高濃度順鉑進(jìn)行培養(yǎng)。順鉑初始培養(yǎng)濃度為1μmol/L,后每輪增加0.5μmol/L,直至將Hela/R細(xì)胞最終培養(yǎng)在含3μmol/L順鉑的培養(yǎng)基中。
1.2 實(shí)驗(yàn)試劑RPIM-1640培養(yǎng)基和胎牛血清購(gòu)自于Gibco公司。順鉑、雷公藤紅素、地高辛、JC-1、噻唑藍(lán)(MTT)、AnnexinⅤ凋亡試劑盒購(gòu)自美國(guó)sigma公司。β-actin、Bcl-2、Bcl-w、Bcl-xl、細(xì)胞色素C抗體購(gòu)自美國(guó)Cell signal公司。ECL試劑盒購(gòu)于美國(guó)Pierce。pcDNA3.1,Lipofectamine 2000購(gòu)于美國(guó)Invitrogen。
1.3 質(zhì)粒構(gòu)建及轉(zhuǎn)染將Bcl-w基因cDNA全長(zhǎng)序列(Gene ID:NM_001199839)以分子克隆的方法與pcDNA3.1連接后構(gòu)建成pcDNA3.1-Bcl-w重組真核表達(dá)質(zhì)粒[5]。使用Lipofectamine 2000按照試劑操作說(shuō)明書(shū)步驟將2μg/mL Bcl-w表達(dá)質(zhì)粒轉(zhuǎn)染入Hela/ R細(xì)胞中,培養(yǎng)24h。
1.4 MTT試驗(yàn)將Hela或Hela/R細(xì)胞按5×103/孔接種在96孔板上。將2μg/mL Bcl-w表達(dá)質(zhì)粒轉(zhuǎn)染到細(xì)胞中,孵育24h,然后再加2μmol/L雷公藤紅素及不同濃度的順鉑培養(yǎng)48h,順鉑0μmol/L為對(duì)照組。之后加5mg/mL MTT 20μL,繼續(xù)培養(yǎng)4h。棄上清,在570nmol/L波長(zhǎng)下用酶標(biāo)儀檢測(cè)OD值,細(xì)胞活力抑制率用以下公式計(jì)算:抑制率=(OD對(duì)照組-OD治療組)/OD對(duì)照組×100%。
1.5 Western blot試驗(yàn)將2μg/mL Bcl-w表達(dá)質(zhì)粒轉(zhuǎn)染到Hela/R細(xì)胞中,孵育24h,然后再加2μmol/ L雷公藤紅素及10μmol/L順鉑培養(yǎng)48h。之后將Hela或Hela/R細(xì)胞用生理鹽水洗滌兩次,之后將細(xì)胞裂解,將蛋白裂解液用12.5%SDS PAGE進(jìn)行分離,之后通過(guò)電轉(zhuǎn)方法將蛋白質(zhì)轉(zhuǎn)到PVDF膜上。將膜放入β-actin、Bcl-2、Bcl-w、Bcl-xl、細(xì)胞色素C一抗稀釋液中孵育過(guò)夜,之后再用二抗稀釋液孵育2h后在X膠片上進(jìn)行曝光,之后用Image J圖像處理軟件進(jìn)行處理,使蛋白表達(dá)灰度值用數(shù)字表示,目標(biāo)蛋白相對(duì)表達(dá)量=目的蛋白灰度值/相應(yīng)β-actin內(nèi)參蛋白灰度值。
1.6 線粒體膜電位測(cè)定將2μg/mL Bcl-w表達(dá)質(zhì)粒轉(zhuǎn)染到Hela/R細(xì)胞中,孵育24h,然后再加2μmol/ L雷公藤紅素及10μmol/L順鉑培養(yǎng)48h后,將細(xì)胞用生理鹽水洗滌兩次,加入5μmol/L JC-1孵育20min,用流式細(xì)胞術(shù)檢測(cè)細(xì)胞的線粒體膜電位。線粒體膜電位喪失的細(xì)胞不發(fā)射JC-1的紅色熒光,因此Hela/R細(xì)胞的線粒體膜電位下降率用未發(fā)出紅色熒光的細(xì)胞占所有細(xì)胞的百分比表示[6]。
1.7 細(xì)胞色素C釋放率測(cè)定將2μg/mL Bcl-w表達(dá)質(zhì)粒轉(zhuǎn)染到Hela/R細(xì)胞中,孵育24h,然后再加2μmol/L雷公藤紅素及10μmol/L順鉑培養(yǎng)48h。之后將Hela/R細(xì)胞重懸在地高辛裂解液中(75μg/mL地高辛溶解在250mmol/L蔗糖水溶液中)孵育15min,之后在15 000g中離心30min,所得的細(xì)胞沉淀中含完整的線粒體,而上清液中不含線粒體[7]。用Western blot方法分別檢測(cè)細(xì)胞沉淀及上清液中細(xì)胞色素C表達(dá)水平,細(xì)胞色素C釋放率用上清液中細(xì)胞色素C蛋白灰度與細(xì)胞沉淀中細(xì)胞色素C蛋白灰度的比值表示。
1.8 細(xì)胞凋亡試驗(yàn)將2μg/mL Bcl-w表達(dá)質(zhì)粒轉(zhuǎn)染到Hela/R細(xì)胞中,孵育24h,然后再加2μmol/L雷公藤紅素及10μmol/L順鉑培養(yǎng)48h。將細(xì)胞用生理鹽水洗滌兩次,按照凋亡試劑盒說(shuō)明書(shū)步驟將Annexin-V加入細(xì)胞中孵育20min,采用流式細(xì)胞術(shù)檢測(cè)腫瘤細(xì)胞的凋亡,細(xì)胞凋亡率用Annexin-V陽(yáng)性細(xì)胞占所有細(xì)胞比值表示。
2.1 雷公藤紅素逆轉(zhuǎn)Hela/R的順鉑耐藥相比于Hela細(xì)胞,Hela/R細(xì)胞對(duì)順鉑顯著耐藥,見(jiàn)表1。盡管低劑量的雷公藤紅素(2μmol/L)單獨(dú)治療對(duì)Hela/ R細(xì)胞僅有微弱的殺傷作用,但顯著增強(qiáng)順鉑對(duì)Hela/R細(xì)胞的殺傷活性,見(jiàn)表2。
表1 順鉑對(duì)Hela及Hela/R細(xì)胞的抑制作用()
表1 順鉑對(duì)Hela及Hela/R細(xì)胞的抑制作用()
注:與對(duì)照組比較,*P<0.05;與相同濃度順鉑處理的Hela細(xì)胞組比較,#P<0.05
組別對(duì)照組1μmol/L順鉑組2μmol/L順鉑組4μmol/L順鉑組8μmol/L順鉑組16μmol/L順鉑組32μmol/L順鉑組64μmol/L順鉑組孔數(shù)順鉑濃度(μmol/L)3 3 3 3 3 3 3 3 0 1 2 4 8 1 6 32 64 Hela細(xì)胞活力抑制率(%)0 18.6±1.5* 23.9±2.4* 47.8±3.9* 63.4±5.4* 72.7±5.9* 85.7±6.7* 91.8±7.9* Hela/R細(xì)胞活力抑制率(%)0 1.9±1.0#3.1±1.2#6.8±1.5*#11.6±1.8*#20.4±2.0*#41.2±3.3*#55.8±4.3*#
2.2 雷公藤紅素通過(guò)Bcl-w途徑逆轉(zhuǎn)Hela/R的順鉑耐藥與Hela相比,Hela/R細(xì)胞的Bcl-2及Bclxl的表達(dá)水平變化不明顯,但Bcl-w的表達(dá)水平顯著提高,見(jiàn)表3。將Hela/R細(xì)胞用雷公藤紅素治療后,腫瘤細(xì)胞中Bcl-w的表達(dá)水平顯著下調(diào),而B(niǎo)cl-2及Bcl-xl的表達(dá)水平未發(fā)生顯著改變,見(jiàn)表4。當(dāng)用Bcl-w表達(dá)質(zhì)粒轉(zhuǎn)染Hela/R細(xì)胞,使細(xì)胞強(qiáng)制表達(dá)Bcl-w后,雷公藤紅素對(duì)順鉑治療的協(xié)同作用喪失,見(jiàn)表5。
表2 雷公藤紅素增強(qiáng)順鉑對(duì)Hela/R細(xì)胞的抑制作用()
表2 雷公藤紅素增強(qiáng)順鉑對(duì)Hela/R細(xì)胞的抑制作用()
注:與對(duì)照組比較,*P<0.05;與10μmol/L順鉑組比較,#P<0.05;與20μmol/L順鉑組比較,△P<0.05;與40μmol/L順鉑組比較,○P<0.05
組別對(duì)照組雷公藤紅素組10μmol/L順鉑組20μmol/L順鉑組40μmol/L順鉑組10μmol/L順鉑+雷公藤紅素組20μmol/L順鉑+雷公藤紅素組40μmol/L順鉑+雷公藤紅素組孔數(shù)順鉑濃度(μmol/L)雷公藤紅素濃度(μmol/L)3 3 3 3 3 3 3 3 0 0 1 0 20 40 10 20 40 0 2 0 0 0 2 2 2 Hela/R細(xì)胞活力抑制率(%)0 6.6±1.1* 12.4±1.2* 27.8±1.9* 45.2±3.1* 57.2±3.9*#71.4±5.1*△84.8±6.8*○
表3 Hela及Hela/R細(xì)胞Bcl-2抗凋亡蛋白家族成員的相對(duì)表達(dá)水平()
表3 Hela及Hela/R細(xì)胞Bcl-2抗凋亡蛋白家族成員的相對(duì)表達(dá)水平()
注:與Hela細(xì)胞組比較,▲P<0.05
組別Hela細(xì)胞組Hela/R細(xì)胞組孔數(shù)3 3灰度比(Bcl-2/β-actin)37.9±1.8 41.4±2.1灰度比(Bcl-xl/β-actin)32.1±1.9 30.2±1.7灰度比(Bcl-w/β-actin)22.1±1.3 70.9±4.9▲
表4 雷公藤紅素下調(diào)Hela/R細(xì)胞中Bcl-w的表達(dá)水平()
表4 雷公藤紅素下調(diào)Hela/R細(xì)胞中Bcl-w的表達(dá)水平()
注:與對(duì)照組比較,*P<0.05
組別對(duì)照組雷公藤紅素組孔數(shù)雷公藤紅素濃度(μmol/L)3 3 0 2灰度比(Bcl-2/β-actin)42.1±2.2 39.5±2.0灰度比(Bcl-xl/β-actin)29.6±1.8 27.4±1.7灰度比(Bcl-w/β-actin)68.9±4.5 29.3±2.6*
表5 Bcl-w表達(dá)質(zhì)粒廢除雷公藤紅素對(duì)順鉑的協(xié)同作用()
表5 Bcl-w表達(dá)質(zhì)粒廢除雷公藤紅素對(duì)順鉑的協(xié)同作用()
注:與對(duì)照組比較,*P<0.05,與順鉑+雷公藤紅素組比較,#P<0.05
組別對(duì)照組順鉑+雷公藤紅素組Bcl-w質(zhì)粒組順鉑+雷公藤紅素+Bcl-w質(zhì)粒組孔數(shù)雷公藤紅素濃度(μmol/L)Bcl-w質(zhì)粒濃度(μg/mL)3 3 3 3順鉑濃度(μmol/L)0 10 0 10 0 2 0 2 0 0 2 2 Hela/R細(xì)胞活力抑制率(%)0 58.9±4.1* 1.0±0.7 17.9±3.1*#
表6 雷公藤紅素聯(lián)合順鉑誘導(dǎo)Hela/R細(xì)胞發(fā)生線粒體途徑的凋亡()
表6 雷公藤紅素聯(lián)合順鉑誘導(dǎo)Hela/R細(xì)胞發(fā)生線粒體途徑的凋亡()
注:與對(duì)照組比較,*P<0.05;與10μmol/L順鉑組比較,#P<0.05;與2μmol/L雷公藤紅素+10μmol/L順鉑組比較,△P<0.05
組別對(duì)照組2μmol/L雷公藤紅素組10μmol/L順鉑組2μmol/L雷公藤紅素+10μmol/L順鉑組2μmol/L雷公藤紅素+10μmol/L順鉑+2μg/ml Bcl-w質(zhì)粒組孔數(shù)3 3 3 3 3線粒體膜電位降低率(%)0 3.2±0.3 6.3±0.6* 45.5±3.1*#11.2±1.2*△細(xì)胞色素C釋放率0.01±0.01 0.03±0.01 0.05±0.01* 0.41±0.03*#0.11±0.02*△細(xì)胞凋亡率(%)1.8±0.4 3.8±0.2 8.3±0.8* 49.4±3.3*#13.8±1.5*△
2.3 雷公藤紅素聯(lián)合順鉑誘導(dǎo)Hela/R細(xì)胞發(fā)生線粒體途徑的凋亡雷公藤紅素顯著增強(qiáng)順鉑對(duì)Hela/R細(xì)胞線粒體膜電位的損傷并促使細(xì)胞色素C從線粒體中釋放到細(xì)胞質(zhì)中,誘導(dǎo)Hela/R細(xì)胞發(fā)生凋亡,見(jiàn)表6。
雷公藤紅素是一種三萜類化合物,來(lái)源于中藥雷公藤的根皮,具有多種生物活性。研究發(fā)現(xiàn),雷公藤紅素具有一定的抗腫瘤效應(yīng),如雷公藤紅素在體外誘導(dǎo)前列腺癌細(xì)胞發(fā)生自噬性死亡[8],還能通過(guò)誘導(dǎo)活性氧簇的生成引起結(jié)腸癌細(xì)胞發(fā)生凋亡[9]。Bcl-2蛋白家族是細(xì)胞凋亡重要調(diào)節(jié)者,其中的Bcl-2抗凋亡蛋白成員(如Bcl-2、Bcl-xl、Bcl-w)能與Bcl-2促凋亡蛋白成員(如Bim、Bax、Bak)的特定位點(diǎn)發(fā)生結(jié)合,從而使這些促凋亡蛋白失去功能而起到凋亡抵抗的作用[10-11]。當(dāng)腫瘤細(xì)胞出現(xiàn)凋亡信號(hào)(如DNA損傷)后,活化的促凋亡蛋白能打開(kāi)腫瘤細(xì)胞的線粒體外膜孔道,使線粒體膜電位喪失,從而促使線粒體來(lái)源的促凋亡物質(zhì)(如細(xì)胞色素C)釋放到細(xì)胞質(zhì)中。細(xì)胞色素C能直接誘導(dǎo)細(xì)胞進(jìn)入caspase依賴的凋亡程序,使腫瘤細(xì)胞發(fā)生凋亡性死亡[12-13]。盡管已經(jīng)有臨床試驗(yàn)證明雷公藤紅素有較好的抗腫瘤療效和安全性[14],但仍然缺乏其與其他抗腫瘤藥物聯(lián)合治療宮頸癌的研究。
在本研究中,筆者構(gòu)建了順鉑耐藥的宮頸癌細(xì)胞模型,用以研究雷公藤紅素是否能逆轉(zhuǎn)腫瘤細(xì)胞對(duì)順鉑的耐藥性,提高化療療效。本研究表明雷公藤紅素確能提高耐藥宮頸癌細(xì)胞對(duì)順鉑的敏感性,顯著降低順鉑的治療濃度。在機(jī)制研究中,筆者通過(guò)Western blot試驗(yàn)發(fā)現(xiàn)耐藥宮頸癌細(xì)胞的Bcl-w表達(dá)水平異常升高,因此推測(cè)雷公藤紅素可能通過(guò)抑制Bcl-w的功能實(shí)現(xiàn)對(duì)順鉑的協(xié)同效應(yīng)。當(dāng)用Bcl-w表達(dá)質(zhì)粒轉(zhuǎn)染Hela/R細(xì)胞,使Hela/R細(xì)胞強(qiáng)制表達(dá)Bcl-w后,筆者發(fā)現(xiàn)雷公藤紅素對(duì)順鉑的協(xié)同效應(yīng)顯著下降,證明了Bcl-w途徑在順鉑耐藥中的重要作用。為了進(jìn)一步研究雷公藤紅素聯(lián)合順鉑殺傷Hela/ R細(xì)胞的機(jī)制,筆者檢測(cè)了腫瘤細(xì)胞的線粒體膜電位和細(xì)胞色素C的釋放。結(jié)果發(fā)現(xiàn)雷公藤紅素聯(lián)合順鉑能誘導(dǎo)耐藥宮頸癌細(xì)胞發(fā)生線粒體的損傷和細(xì)胞色素C的釋放,進(jìn)而促使耐藥宮頸癌細(xì)胞發(fā)生凋亡性死亡。
綜上所述,本研究結(jié)果證明了雷公藤紅素在體外能提高順鉑對(duì)耐藥宮頸癌細(xì)胞的殺傷活性,其分子機(jī)制可能為通過(guò)抑制Bcl-w的功能,提高促凋亡蛋白的活性,進(jìn)而促進(jìn)耐藥宮頸癌細(xì)胞在順鉑的治療下發(fā)生線粒體途徑的凋亡。
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(收稿:2015-11-13修回:2016-02-26)
An Active Component of Chinese Traditional Medicine Celastrol Reverses the Cisplatin-resistance of Cervical Cancer
SUN Juping1,JIANG Kai2.1 Clinical Laboratory,the Second Affiliated Hospital of Zhejiang ChineseMedicineUniversity,Hangzhou(310005),China;2ClinicalLaboratory,TongdeHospitalofZhejiangProvince, Hangzhou(310012),China
ObjectiveTo investigate the effect traditionl Chinese medicine celastrol on reversing the cisplatinresistance in cervical cancer cell line Hela/R and the underlying mechanism.MethodsThe cisplatin-resistant Hela/R cell line was established via stepped exposure to cisplatin.MTT assay was performed to explore whether the celastrol can enhance the cytotoxicity of cisplatin to Hela/R cells.The expression of Bcl-2,Bcl-w and Bcl-xl was evaluated by using western blot analysis.The mitochondrial membrane potential and apoptotic rate of Hela/R was determined by flow cytometry.ResultsThe viability inhibition of Hela and Hela/R cells treated with cisplatin was as follows:18.6%±1.5%(Hela)and 1.9%±1.0%(Hela/R)in 1μmol/L cisplatin group;23.9%±2.4%(Hela)and 3.1%±1.2%(Hela/R)in 2μmol/L cisplatin group;47.8%±3.9%(Hela)and 6.8%±1.5%(Hela/R)in 4μmol/L cisplatin group;63.4%±5.4%(Hela)and 11.6%±1.8%(Hela/R)in 8μmol/L cisplatin group;72.7%±5.9%(Hela)and 20.4%± 2.0%(Hela/R)in 16μmol/L cisplatin group;85.7%±6.7%(Hela)and 41.2%±3.3%(Hela/R)in 32μmol/L cisplatin group;91.8%±7.9%(Hela)and 55.8%±4.3%(Hela/R)in 64μmol/L cisplatin group;significant differences were found between two groups(all P<0.05).The viability inhibition of Hela/R cells treated with celastrol plus cisplatinwas as follows:6.6%±1.1%in 2μmol/L celastrol group;12.4%±1.2%in 10μmol/L cisplatin group;27.8%±1.9%in 20μmol/L cisplatin group;45.2%±3.1%in 40μmol/L cisplatin group;57.2%±3.9%in 10μmol/L cisplatin+celastrol group;71.45±5.1%in 20μmol/L cisplatin+celastrol group;84.8%±6.8%in 40μmol/L cisplatin+celastrol group;the viability inhibition was better in celastrol plus cisplatin groups than that in cisplatin single groups(all P<0.05).The level of Bcl-w/β-actin in Hela/R cells was higher than that in Hela cells(70.9±4.9 vs 22.1±1.3,P<0.05);the level of Bcl-2/β-actin and Bcl-xl/β-actin was not different between Hela cells and Hela/R cells(P>0.05).Compared with control group,celastrol inhibited the expression of Bcl-w/β-actin in Hela/R cells(29.3±2.6 vs 68.9±4.5,P<0.05).Celastrol significantly enhanced the damage of mitochondrial membrane potential induced by cisplatin in Hela/R,leading to the release of cytochrome C and the induction of apoptosis.ConclusionCelastrol enhances the cytotoxicity of cisplatin to Hela/R cells via inhibiting the function of Bcl-w,promoting the activity of pro-apoptotic proteins,resulting in the activity of mitochondria-related apoptosis in cisplatin-resistant cervical cancer cells.
drug-resistant cervical cancer cell line;cisplatin;Hela/R;celastrol;Bcl-w;mitochondria;apoptosis
1浙江中醫(yī)藥大學(xué)附屬第二醫(yī)院檢驗(yàn)科(杭州310005);2浙江省立同德醫(yī)院檢驗(yàn)科(杭州310012)
姜?jiǎng)P,Tel:15382362622;E-mail:wzjiangkai@163.com