劉靜波,郭晨旭,張文淵,馬玲*
(1安徽蚌埠醫(yī)學院第一附屬醫(yī)院腫瘤婦科,蚌埠 233004;2安徽蚌埠醫(yī)學院第一附屬醫(yī)院腫瘤外科,蚌埠 233004)
奈達鉑抑制卵巢癌OVCAR-3細胞增殖及下調Hedgehog信號通路相關蛋白水平
劉靜波1,郭晨旭2,張文淵2,馬玲1*
(1安徽蚌埠醫(yī)學院第一附屬醫(yī)院腫瘤婦科,蚌埠 233004;2安徽蚌埠醫(yī)學院第一附屬醫(yī)院腫瘤外科,蚌埠 233004)
目的觀察PTCH1在卵巢癌組織中的表達,探討奈達鉑抑制卵巢癌OVCAR-3細胞的增殖以及對Hedgehog信號通路相關蛋白表達的影響。方法應用免疫組織化學染色法檢測正常卵巢組織及卵巢癌標本各80例中PTCH1的表達,并觀察卵巢癌組織標本中PTCH1表達的規(guī)律及其與病理類型、病理分級、淋巴結轉移、臨床分期、是否行新輔助化療之間的關系。常規(guī)培養(yǎng)卵巢癌細胞OVCAR-3,奈達鉑干預后Western blot觀察細胞中PTCH1、cyclin D1及Gli1的表達變化情況,CCK-8法檢測細胞增殖能力的變化。結果PTCH1在卵巢癌標本表達率明顯高于正常卵巢組織,PTCH1的表達與病理類型、病理分級、淋巴結轉移、臨床分期無明確聯(lián)系,但與含奈達鉑方案的新輔助化療的執(zhí)行相關;奈達鉑干預的卵巢癌細胞中PTCH1、cyclin D1及Gli1的表達較未干預組低,其增殖受到明顯抑制。結論奈達鉑可以通過干擾卵巢癌中Hedgehog通路關鍵因子從而影響卵巢癌的發(fā)生發(fā)展。
PTCH;Hedgehog信號通路;卵巢癌;奈達鉑
卵巢癌是女性生殖系統(tǒng)中最常見的惡性腫瘤之一,發(fā)病率位于第三位,因卵巢深居盆腔,早期癌變后癥狀不易察覺,許多患者至醫(yī)院就診時,病期已為進展期或晚期,并且由于其復雜的病理類型及組織學特異性,病死率位于女性生殖系統(tǒng)惡性腫瘤的第一位[1]。
Hedgehog(Hh)信號通路是調節(jié)胚胎發(fā)育中的經(jīng)典通路之一,Hh信號通路的激活與許多腫瘤的形成相關,主要由信號分子Shh、膜受體patched(PTCH)、smothened(Smo)、與中間傳遞分子和核轉錄因子Gli1組成[2]。Hh還可以通過促進轉錄因子cyclin E及cyclin D功能抑制Rb基因的功能促進細胞增殖[3,4]。過度表達cyclin D則可以促進細胞生長。這個發(fā)現(xiàn)證實Hh信號系統(tǒng)的活化與腫瘤形成相關。已有研究表明,在多種惡性腫瘤中Hh信號通路的關鍵因子都有表達[5-8]。也確有學者證實卵巢腫瘤中存在Hh信號通路,并在部分卵巢腫瘤中存在過度激活的現(xiàn)象[9]?;熓锹殉矏盒阅[瘤不可缺少的治療手段,卵巢上皮性腫瘤的化療一線藥物是紫杉醇+鉑類。本研究檢測了曾接受含奈達鉑新輔助化療的患者卵巢癌大體標本中PTCH1的表達,并檢測奈達鉑干預后卵巢癌細胞中Hh信號通路成員分子Gli1以及與Hh通路相關的細胞周期的關鍵因子cyclin D1的表達,同時檢測奈達鉑對卵巢癌細胞的增殖影響,以探討奈達鉑通過Hh信號通路對卵巢癌的治療作用機制。
收集2012年1月至2016年6月蚌埠醫(yī)學院第一附屬醫(yī)院婦腫瘤婦科和婦產(chǎn)科術后存檔蠟塊共80例卵巢癌患者,包含漿液性囊腺癌、黏液性囊腺癌、子宮內膜樣癌和透明細胞癌,常規(guī)制片。上述病例均為原發(fā)性卵巢上皮細胞癌,含奈達鉑方案新輔助化療的病例為25例。另選80例正常卵巢組織的存檔蠟塊,常規(guī)制片。
人卵巢癌細胞株OVCAR-3購自中國科學院武漢細胞庫。改良型RPMI1640全培養(yǎng)含20%胎牛血清、1%青鏈霉素雙抗(青霉素100iu/ml,鏈霉素100mg/ml)。37℃、5%CO2無菌培養(yǎng)箱培養(yǎng),每2d換液,3~5d以0.25%胰蛋白酶-EDTA消化后傳代。
Elivision plus免疫組織化學試劑盒(深圳新產(chǎn)業(yè)生物醫(yī)學工程股份有限公司),液體DAB酶底物顯色試劑盒(上海信然生物科技有限公司),兔抗人PTCH1蛋白一抗(ab53715)和兔抗人Gli1蛋白一抗(ab151796)(英國Abcam公司),兔抗人cyclin D1蛋白一抗(WL01435a)(萬類生物科技公司),山羊抗兔IgG二抗(Biosharp公司),RIPA細胞裂解液(碧云天公司),奈達鉑(江蘇奧賽康公司)。
將石蠟切片脫蠟、脫苯、水化后,PBS沖洗3次(3min/次),放入裝有EDTA修復液的修復盒中,用高壓鍋進行抗原修復;滴加過氧化物酶阻斷劑,室溫孵育10min;PBS沖洗3次(3min/次),甩凈PBS液后,切片上滴加PTCH1蛋白一抗,室溫孵育60min。PBS沖洗后于切片上滴加二抗,室溫孵育20min;PBS沖洗后滴加過氧化物酶聚合物,室溫孵育30min,PBS沖洗后,滴加DAB顯色劑,3~10min后純水充分沖洗,蘇木素復染3min,純水充分沖洗后鹽酸酒精分化,PBS反藍;梯度酒精脫水、二甲苯透明后中性樹膠封片。
OVCAR-3細胞實驗組細胞培養(yǎng)液中加入30ug/ml[10,11]奈達鉑后培養(yǎng)24h,對照組常規(guī)培養(yǎng)。RIPA細胞裂解液處理收集的OVCAR-3細胞從而提取細胞總蛋白,BCA蛋白測定試劑盒測定蛋白濃度,利用細胞裂解液調定濃度至60μg/μl,煮沸5min,定量10μl蛋白,按分組加入泳道內,SDS-PAGE電泳后恒流轉膜。取出轉膜完成的PVDF膜浸于5%脫脂牛奶中封閉,將PVDF膜與一抗稀釋溶液(β-actin稀釋比例為 1∶500,PTCH1 為 1∶1000,cyclin D1 為1∶1500,Gli1 為 1∶3000)封閉于抗體孵育盒內,4℃孵育過夜。TBST液洗膜后與二抗稀釋溶液(稀釋比例1∶6000)封閉于抗體孵育盒內,4℃孵育1h。TBST液洗膜后底物顯色劑曝光,掃描曝光后應用Quantity one軟件分析掃描蛋白條帶的光密度值,計算蛋白的相對表達量(目的蛋白光密度值/β-actin光密度值)。
收集細胞后分實驗組和對照組。實驗組的細胞培養(yǎng)液中含30μg/ml奈達鉑,對照組細胞培養(yǎng)液無奈達鉑。重懸后細胞計數(shù),將細胞濃度調整至1×104/ml,加入96孔板,37℃、5%CO2常規(guī)培養(yǎng),期間常規(guī)換液。每個時間點取3孔實驗組和1孔對照組,提前3h各加入Cell Counting Kit-8(CCK-8)溶液10μl,除去氣泡后繼續(xù)培養(yǎng)3h,酶標儀讀取培養(yǎng) 6h、24h、48h、72h、96h、120h、144h、168h 后的490 nm處吸光度值(OD490)。
SPSS 19.0 for win進行數(shù)據(jù)分析,計量資料以±s 表示時,兩兩比較t檢驗;計量資料以百分率表示時,PTCH1的表達與臨床病理參數(shù)之間的關系x2檢驗,期望值<5時采用Fisher精確檢驗。
正常卵巢組織中PTCH1多呈陰性,偶見弱陽性表達;卵巢癌組織中PTCH1表達呈陽性或強陽性(圖1)。PTCH1蛋白在卵巢癌中的表達率明顯高于正常卵巢組織(83.75% vs 7.5%,P<0.01)(表1),在早期(I、Ⅱ期)和晚期(Ⅲ、Ⅳ期)病例組織中的陽性表達率分別為80.00%和 86.00%,在高/中分化、低分化卵巢癌組織中的陽性表達率分別為86.84%和83.33%;在漿液性卵巢癌、粘液性卵巢癌、子宮內膜樣癌和透明細胞癌組織中的陽性表達率為83.78%、85.19%、80.00%和83.33%;在有、無淋巴結轉移的病例組織中的陽性表達率分別為84.09%和83.33%;在經(jīng)奈達鉑新輔助化療后和未行新輔助化療的的標本中陽性表達率為68.00%和90.91%(表2)。實驗結果顯示,PTCH1蛋白的表達與卵巢癌組織的期別、細胞分化程度、淋巴結轉移及細胞組織學類型均無明顯關系(P>0.05),但與是否新輔助化療存在明顯相關性,表現(xiàn)為新輔助化療后的標本中PTCH1的表達率較未新輔助化療的標本低(P<0.05)。
表1 PTCH1在正常卵巢組織與卵巢癌組織中陽性表達率Tab. 1 The positive expression rate of PTCH1 in normal ovarian tissues and ovarian carcinoma tissues
表 2 PTCH1在卵巢癌組織中的表達及與臨床病理特征間的相關聯(lián)系Tab. 2 Correlation of PTCH1 expression in ovarian carcinoma with clinical pathological features
圖 1 PTCH1在正常卵巢組織(A)與卵巢癌組織(B)中的免疫組織化學表達。比例尺,50μmFig. 1 The immunohistochemical expression of PTCH1 protein in normal ovarian tissues (A) and ovarian carcinoma tissues (B). Scale bar, 50μm
Western blot檢測發(fā)現(xiàn),對照組OVCAR-3細胞中PTCH1、cyclin D1、Gli1相對表達量分別為0.762±0.021、1.161±0.002和 1.461±0.027; 經(jīng)奈達鉑干預后的OVCAR-3細胞中PTCH、cyclin D1及Gli1的相對表達量分別為0.389±0.023、0.583±0.004和0.614±0012,3種蛋白的相對表達量均低于未干預組(P<0.05)(圖2)。
圖 2 奈達鉑對OVCAR-3細胞中PTCH1、cyclin D1及Gli1水平的影響。A,代表性Western-blot檢測結果;B,奈達鉑干預對 PTCH、cyclin D1和Gli1水平影響的統(tǒng)計學分析; **:與未處理對照組比較,P<0.01(n=3)Fig. 2 effect of nedaplatin on PTCH1, cyclin D1 and Gli1 expression levels in OVCAR-3 cells. A, representative Western-blot results; B, statistical analysis of nedaplatin effect on PTCH1, cyclin D1 and Gli1 expression levels in OVCAR-3 cells detected by Western-blot; **∶ P<0.01, compared with untreated control group(n=3)
利用CCK-8法檢測奈達鉑對OVCAR-3細胞增殖的影響顯示,與未處理對照組相比,經(jīng)奈達鉑干預后的OVCAR3細胞的增殖明顯受到抑制(圖3)。
圖3 奈達鉑抑制OVCAR-3細胞的增殖。CCK-8法檢測奈達鉑對OVCAR-3細胞增殖影響的統(tǒng)計學分析;與未處理對照組比較:**,P<0.01(n=3)Fig. 3 The effects of nedaplatin on OVCAR-3 cell proliferation. Statistical analysis OVCAR-3 cell proliferation detected by CCK-8; **, P<0.01,compared with untreated control group (n=3)
卵巢癌在女性生殖系統(tǒng)惡性腫瘤中預后最差,卵巢癌的基礎研究通常從基因信號通路出發(fā)探討其分子生物學特性,尋求卵巢癌的臨床治療策略。紫杉醇聯(lián)合卡鉑/順鉑方案是目前被廣泛應用的卵巢癌一線化療方案,但因其產(chǎn)生耐藥現(xiàn)象,影響了臨床療效。奈達鉑是新一代鉑類抗癌藥物,它具有10倍于順鉑的水溶性,其抗腫瘤的機理是阻礙DNA的復制,其腎毒性和消化道毒性要輕于其他鉑類,抗腫瘤活性與順鉑相當,并強于卡鉑,而且與順鉑、卡鉑無完全交叉耐藥性,是患者在對順鉑、卡鉑耐藥后的絕佳選擇[17]。
本實驗結果顯示,卵巢癌組織中PTCH1的表達呈陽性或強陽性,且與腫瘤期別、腫瘤病理類型、腫瘤病理分級、有無淋巴結轉移無明顯相關性,而與是否行奈達鉑新輔助化療相關,這說明PTCH1在卵巢癌的發(fā)生發(fā)展中可能確實存在著異常的激活,并顯示奈達鉑可以有效的降低卵巢癌中PTCH1的表達。Western blot的結果也進一步證實了卵巢癌細胞中PTCH1的表達升高,同時Gli1和cyclin D1的表達也是增高的。說明Hh信號通路及其相關蛋白著實參與了卵巢癌的發(fā)生發(fā)展,并且扮演著促進者的角色。在Hh信號通路中,膜受體PTCH、SMO及轉錄因子Gli1尤其重要,PTCH常態(tài)下與SMO相結合能夠抑制下游基因的表達,當PTCH增加,活化的Shh(PTCH是Shh的配體)能夠與之結合并解除與SMO的結合從而解除抑制效果,向下傳導,并激活Gli1,引起細胞的非程序的無限制增殖,形成腫瘤趨勢,而促使細胞增殖最直接的途徑即是細胞周期蛋白的激活,Cyclin D1又是最重要的細胞周期蛋白之一,同時也有研究證實,Hh信號轉導途徑可以促進Cyclin D1的表達。
細胞的生長與增殖受到Hh信號通路控制,而奈達鉑干預后的卵巢癌細胞中Hh信號通路相關的因子被調低,意味著會對卵巢癌細胞的增殖產(chǎn)生一定的影響。本實驗證實了在奈達鉑干預后卵巢癌細胞的增殖明顯受到抑制,這一效應這也就為奈達鉑通過Hh通路影響卵巢癌的發(fā)生發(fā)展提供了最終效應證據(jù)。
本實驗進一步證實了卵巢腫瘤中存在Hh信號通路,實驗的意義及遠期應用的前景為:PTCH1蛋白的檢測可能用于臨床上對于卵巢腫瘤發(fā)生危險的相關性指標并作為腫瘤標記物,可能用于卵巢癌的診斷。同時也為卵巢癌的靶向治療和基因治療提供新的方向。課題組接下來將繼續(xù)深入探討卵巢癌發(fā)生發(fā)展中Hh信號通路的作用機制,更全面為卵巢癌的基因靶向治療提供一條扎實可行的道路。
[1] Sopik V, Rosen B, Giannakeas V, et al. Why have ovarian cancer mortality rates declined? Part III. Prospects for the future. Gynecol Oncol, 2015, 138(3)∶ 757-761.
[2] Vered M, Peleg O, Taicher S, et al. The immunoprofile of odontogenic keratocyst (keratocystic odontogenic tumor)that includes expression of PTCH, SMO, GLI‐1 and bcl‐2 is similar to ameloblastoma but different from odontogenic cysts. J Oral Pathol Med, 2009, 38(7)∶ 597-604.
[3] Kenney AM, Rowitch DH. Sonic hedgehog promotes G(1)cyclin expression and sustained cell cycle progression in mammalian neuronal precursors. Mol Cell Biol, 2000,20(23)∶ 9055-9067.
[4] Lin Z, Sheng H, You C, et al. Inhibition of the Cyclin D1 promoter in response to sonic hedgehog signaling pathway transduction is mediated by Gli1. Exp Ther Med, 2017,13(1)∶ 307-314.
[5] Huang S, He J, Zhang X, et al. Activation of the hedgehog pathway in human hepatocellular carcinomas.Carcinogenesis, 2006, 27(7)∶1334-1340.
[6] Watkins DN,Berman DM,Burkholder SG,et al. Hedgehog signalling within airway epithelial progenitors and in smallcell lung Cancer. Nature, 2003, 422(6929)∶ 313-317.
[7] Sanchez P, Hernández AM, Stecca B, et al. Inhibition of prostate Cancer proliferation by interference with SONIC HEDGEHOG-GLI1 signaling. Proc Natl Acad Sci U S A,2004, 101(34)∶ 12561-12566.
[8] Fernández-Zapico ME. Primers on molecular pathways GLI∶more than just hedgehog? Pancreatology, 2008, 8(3)∶ 227-229.
[9] Lan C, Choi Y, Buckanovich R. Abstract B72∶ Identification of hedgehog signaling between ovarian tumors and carcinoma associated mesenchymal stem cells. Clin Cancer Res, 2013, 19(19_Suppl)∶ B72-B72.
[10] Monk BJ, Alberts DS, Burger RA, et al. In vitro phase II comparison of the cytotoxicity of a novel platinum analog,nedaplatin (254-S), with that of cisplatin and carboplatin against fresh, human cervical cancers. Gynecol Oncol, 1998,71(2)∶ 308-312.
[11] 談華陽,蘇翔宇,李蘇宜. 奈達鉑聯(lián)合順鉑體外干預人卵巢癌Skov-3細胞生長的實驗研究. 臨床腫瘤學雜志,2009,14(4):301-305.
[12] Lee Y, Miller HL, Russell HR, et al. Patched 2 modulates tumorigenesis in Patched1 heterozygous mice. Cancer Res,2006, 66(14)∶ 6964-6971.
[13] Chen Y, Struhl G. Dual roles for patched in sequestering and transducing Hedgehog. Cell, 1996, 87(3)∶ 553-563.
[14] Cai FG, Xiao JS, Ye QF. Effects of ischemic preconditioning on cyclinD1 expression during early ischemic reperfusion in rats. World J Gastroenterol, 2006, 12(18)∶ 2936-2940.
[15] Lobjois V, Benazeraf B, Bertrand N, et al. Specific regulation of cyclins D1 and D2 by FGF and Shh signaling coordinates cell cycle progression, patterning, and differentiation during early steps of spinal cord development. Developmental biology, 2004, 273(2)∶ 195-209.
[16] Chen X, Horiuchi A, Kikuchi N, et al. Hedgehog signal pathway is activated in ovarian carcinomas, correlating with cell proliferation∶ it’s inhibition leads to growth suppression and apoptosis. Cancer sci, 2007, 98(1)∶ 68-76.
[17] Alberto ME, Lucas MF, Pavelka M, et al. The secondgeneration anticancer drug Nedaplatin∶ a theoretical investigation on the hydrolysis mechanism. J Phys Chem B,2009, 113(43)∶ 14473-14479.
Nedaplatin inhibits ovarian cancer OVCAR-3 cell proliferation and downregulates Hedgehog signaling proteins
Liu Jingbo1, Guo Chenxu2, Zhang Wenyuan2, Ma Ling1*(1Department of Gynecologic Oncology, The First Affiliated Hospital of Bengbu Medical College, Bengbu 233004, China;2Department of Surgical Oncology, The First Affiliated Hospital of Bengbu Medical College, Bengbu 233004, China)
ObjectiveTo invesitgate the expression of PTCH1 in ovarian cancer tissues and the inhibitory effect of nedaplatin on ovarian cancer cell proliferation as well as its influence on the Hedgehog signaling pathways.MethodsThe expression of PTCH1 in normal ovarian and ovarian cancer tissues (80 cases of each) was detected using immunohistochemical staining. The correlation between PTCH1 expression and tumor pathological type and grade, lymph node metastasis, clinical stage, and neoadjuvant chemotherapy was investigated. In cultured ovarian cancer cells, the expression of PTCH1, cyclin D1 and Gli1 in response to nedaplatin treatment were further evaluated by Western blotting, and the cell proliferation was determined by CCK-8.ResultsThe expression level of PTCH1 in ovarian cancer was significantly higher than that in normal ovarian tissues, which was not associated with pathological type,pathological grade, lymph node metastasis and clinical stage. However, neoadjuvant chemotherapy reduced the positive expression rate of PTCH1. The expression of PTCH1, cyclin D1 and Gli1 in nedaplatin treated ovarian cancer cells was lower than that in the untreated group. The proliferation of ovarian cancer cells was significantly inhibited after nedaplatin treatment.ConclusionNedaplatin can affect the development of ovarian cancer by interfering with the key factors of Hedgehog pathway in ovarian cancer.
PTCH1; patched-1; ovarian cancer; nedaplatin
R737.3
A DOI:10.16705/ j. cnki. 1004-1850. 2017. 05. 009
2017-03-30
2017-09-11
蚌埠醫(yī)學院科技發(fā)展基金項目(Byk fl 2A15)
劉靜波,女(1987年),漢族,碩士,住院醫(yī)師
*通訊作者(To whom correspondence should be addressed):ml1970222@163.com