胡 濱,范楚苓,徐曉軍,3,趙 明,劉亞坤,李菲菲
乳腺癌組織中RunX2基因的表達(dá)水平及臨床意義分析
胡 濱1,2,范楚苓1,徐曉軍1,3,趙 明1,劉亞坤1,李菲菲1
目的 探討乳腺癌和癌旁組織中核心結(jié)合因子(RunX2)基因的表達(dá)差異及其與乳腺癌患者的臨床特征和預(yù)后的關(guān)系。方法 選擇75例乳腺癌患者癌組織標(biāo)本,所有患者術(shù)前未經(jīng)放療和化療,采用免疫組化法檢測(cè)乳腺癌組織和癌旁組織RunX2的表達(dá)情況。分析乳腺癌患者RunX2基因的表達(dá)與年齡、病理分型、術(shù)后分期、淋巴轉(zhuǎn)移、腫瘤大小、雌激素受體(ER)表型、孕激素受體(PR)表型、人類(lèi)表皮生長(zhǎng)因子2(HER2)表型、ki67表達(dá)水平以及生存率的關(guān)系。結(jié)果 75例患者的癌組織中有44例乳腺癌組織高表達(dá)RunX2,31例組織低表達(dá)RunX2;而癌旁組織僅23例高表達(dá),52例均表達(dá)較低。癌組織和癌旁組織中RunX2的表達(dá)水平差異有統(tǒng)計(jì)學(xué)意義(P<0.05)。RunX2基因的表達(dá)高低與患者年齡、術(shù)后分期、淋巴結(jié)轉(zhuǎn)移、病理類(lèi)型、PR表型、HER2表型無(wú)明顯相關(guān)性,但是與患者的ER表型和ki67表達(dá)相關(guān)(P<0.05),并且高表達(dá)RunX2患者術(shù)后3年的總體生存率較低表達(dá)患者差。結(jié)論 乳腺癌組織中RunX2基因高表達(dá)與患者的ER表型和臨床預(yù)后呈正相關(guān)性,進(jìn)一步證實(shí)了RunX2在乳腺癌發(fā)生發(fā)展中起到重要作用。
乳腺癌;RunX2;雌激素受體;臨床預(yù)后
乳腺癌是女性最常見(jiàn)的惡性腫瘤之一,全球每年約有170萬(wàn)新發(fā)病例,約50萬(wàn)人死亡,居癌癥發(fā)生率和死亡率的首位[1]。RunX2又稱(chēng)核心結(jié)合因子(core binding factor-α,RunX2),屬于runt域基因家族,是一種參與骨髓間質(zhì)干細(xì)胞成骨分化和骨發(fā)育的重要轉(zhuǎn)錄因子[2]。研究[3-4]表明 RunX2和多種腫瘤的發(fā)生密切相關(guān),已被證明在成骨與骨肉瘤的發(fā)生發(fā)展過(guò)程中起重要作用,是骨髓間質(zhì)干細(xì)胞成骨分化和骨發(fā)育的重要轉(zhuǎn)錄因子,通過(guò)促進(jìn)溶骨作用、促進(jìn)腫瘤血管新生等多個(gè)途徑轉(zhuǎn)移癌細(xì)胞的生長(zhǎng)。除了骨組織外,乳腺是RunX2的表達(dá)量最高的組織之一,報(bào)道[5]顯示在臨床預(yù)后差的乳腺癌中異常高表達(dá),為進(jìn)一步了解RunX2與乳腺癌之間的關(guān)系,該研究采用免疫組化法檢測(cè)RunX2基因在乳腺癌和癌旁正常組織中的表達(dá)情況,并且分析其表達(dá)與年齡、病理分型、術(shù)后分期、淋巴轉(zhuǎn)移、腫瘤大小、雌激素受體(estrogen receptor,ER)表型、孕激素受體(progesterone receptor,PR)表型、人類(lèi)表皮生長(zhǎng)因子 (human epidermal growth factor receptor-2,HER2)表型、ki67表達(dá)水平以及生存率的關(guān)系。為進(jìn)一步揭示RunX2與乳腺癌的發(fā)生、發(fā)展和預(yù)后之間聯(lián)系奠定基礎(chǔ)。
1.1 病例資料 選擇2009年1月~2012年12月間于安慶市第一人民醫(yī)院胃腸甲乳外科及安徽醫(yī)科大學(xué)第一附屬醫(yī)院乳腺外科確診為乳腺癌患者的乳腺癌組織標(biāo)本75例。所有患者為女性,年齡33~81 (65.60±0.78)歲。術(shù)前未行放療和化療。術(shù)后分期Ⅰ~Ⅱ期39例,Ⅲ~Ⅳ期36例。導(dǎo)管侵潤(rùn)癌53例,非導(dǎo)管侵潤(rùn)癌22例。有淋巴結(jié)轉(zhuǎn)移42例,無(wú)淋巴結(jié)轉(zhuǎn)移33例。75例乳腺癌組織中,ER陽(yáng)性34例,PR陽(yáng)性36例,HER2陽(yáng)性39例,ki67高表達(dá)46例。
1.2 免疫組化 采用SP法將腫瘤固定后,脫水,制成蠟塊,標(biāo)本蠟塊連續(xù)切片,確保切片厚度不大于2 μm,常規(guī)二甲苯脫蠟,使用H2O2去離子水消除內(nèi)源性過(guò)氧化物酶活性,PBS沖洗2次,一抗1∶500配置,4℃過(guò)夜孵育,孵育結(jié)束后使用PBS清洗3次,室溫使用與一抗對(duì)應(yīng)二抗孵育15~20 min,PBS清洗3次,每次5 min,辣根酶標(biāo)記鏈霉素卵白素工作液滴加至標(biāo)本,室溫孵育15 min,PBS清洗3次,每次5 min,DAB顯色,使用蘇木精染色,然后鹽酸乙醇分化,酒精按梯度脫水,二甲苯透明后,封片,至顯微鏡下觀察,拍照分析。
1.3 結(jié)果判定 采用雙盲法閱片,細(xì)胞染色成棕黃色為陽(yáng)性細(xì)胞。RunX2基因陽(yáng)性染色主要定位在細(xì)胞核。根據(jù)陽(yáng)性細(xì)胞個(gè)數(shù)占整個(gè)腫瘤細(xì)胞的百分率計(jì)分,<5%為0分,5%~25%為1分,26%~50% 為2分,51%~75%為3分,>75%為4分。再根據(jù)陽(yáng)性細(xì)胞染色深淺計(jì)分,不著色為0分,淡黃色為1分,棕黃色為2分,棕褐色為3分,最后將兩者分?jǐn)?shù)相乘,0分為陰性(-),1~4分為陽(yáng)性(+),5~8分為弱陽(yáng)性(++),9~12分為強(qiáng)陽(yáng)性(+++),以(-)和(+)視為陰性/低表達(dá),(++)以上表達(dá)者視為高表達(dá)。
表1 RunX2表達(dá)水平高低和乳腺癌患者臨床病理特征的關(guān)系(n)
1.4 統(tǒng)計(jì)學(xué)處理 采用SPSS 16.0軟件進(jìn)行分析。臨床指標(biāo)相關(guān)性分析采用 χ2檢驗(yàn),采用Kaplan-Meier生存曲線(xiàn)分析生存率差異。
2.1 癌組織和癌旁組織中RunX2基因的表達(dá)水平分析 75例乳腺癌組織中有44例乳腺癌組織中RunX2高表達(dá),高表達(dá)率為58.7%;31例陰性/低表達(dá),陰性/低表達(dá)率41.3%。與此同時(shí),癌旁組織中23例高表達(dá),52例陰性/低表達(dá),χ2檢驗(yàn)表明癌組織和癌旁組織RunX2高表達(dá)率明顯增加(χ2=14.67,P<0.05)。
2.2 RunX2基因的表達(dá)與乳腺癌臨床病理特征和患者預(yù)后的關(guān)系 RunX2基因的表達(dá)與乳腺癌患者的年齡、術(shù)后分期、病理類(lèi)型、淋巴結(jié)轉(zhuǎn)移間差異無(wú)統(tǒng)計(jì)學(xué)意義。在分子表型上,RunX2基因的表達(dá)與乳腺癌組織中ER表型及ki67的表達(dá)相關(guān)(圖2),差異具有統(tǒng)計(jì)學(xué)意義(P<0.05),但與PR、HER2的表達(dá)差異無(wú)統(tǒng)計(jì)學(xué)意義,見(jiàn)表1。
75例乳腺癌患者術(shù)后均接受化療,其中49例可作生存期分析。Log-Rank檢驗(yàn)顯示49例患者RunX2高表達(dá)和低表達(dá)患者術(shù)后3年總生存率分別為70%(95%置信區(qū)間:0.51~0.83)和43%(95%置信區(qū)間:0.32~0.54),Log-Rank檢驗(yàn)分析顯示RunX2高、低表達(dá)組在生存過(guò)程中存在明顯差異(χ2=27.99,P<0.05)(圖3),高表達(dá)組患者總體預(yù)后較差。
圖1 免疫組化法檢測(cè)患者乳腺癌組織
研究[6]顯示RunX2為骨母細(xì)胞特異性轉(zhuǎn)錄因子,在骨母細(xì)胞的發(fā)育、分化和骨形成過(guò)程中起著重要的作用,隨后的一系列研究[7-8]表明RunX2在多種腫瘤的發(fā)生發(fā)展中也發(fā)揮了重要作用,已被證明在成骨與骨肉瘤的發(fā)生發(fā)展過(guò)程中起重要作用,通過(guò)促進(jìn)溶骨作用對(duì)腫瘤血管新生等多個(gè)途徑促進(jìn)癌細(xì)胞的生長(zhǎng)轉(zhuǎn)移。尤其是近年來(lái)RunX2被證明與乳腺癌的發(fā)展密切相關(guān),多個(gè)研究[9-10]均報(bào)道在臨床預(yù)后差的乳腺癌中RunX2高表達(dá),并且可能與乳腺癌的ER、PR和HER2分子亞型密切相關(guān)。但是RunX2的表達(dá)水平、與臨床病理特征的關(guān)系以及對(duì)患者預(yù)后的影響的研究一直不確切。這使得是否能將RunX2作為診斷、治療和預(yù)后的分子標(biāo)記物等帶來(lái)了爭(zhēng)議。
圖2 免疫組化分析不同乳腺癌患者組織中ER、ki67與RunX2表達(dá)的相關(guān)性 ×40
圖3 49例患者RunX2表達(dá)水平相關(guān)的生存曲線(xiàn)分析
本研究通過(guò)對(duì)75例乳腺癌患者組織的檢測(cè),結(jié)果顯示癌組織中有44例高表達(dá)RunX2、31例組織低表達(dá)RunX2;而癌旁組織僅23例高表達(dá)、52例均表達(dá)較低。癌組織和癌旁組織中RunX2的表達(dá)差異有統(tǒng)計(jì)學(xué)意義。這一結(jié)果進(jìn)一步支持了RunX2表達(dá)上調(diào)與乳腺癌的發(fā)生發(fā)展相關(guān)。隨后對(duì)RunX2基因的表達(dá)高低與患者的臨床病理特征進(jìn)行分析,結(jié)果顯示在這75例患者中RunX2表達(dá)水平與年齡、術(shù)后分期、淋巴結(jié)轉(zhuǎn)移、病理類(lèi)型無(wú)明顯相關(guān)性,但是與患者的ER表型和患者術(shù)后生存率相關(guān)。ER是乳腺細(xì)胞生長(zhǎng)、分化的重要調(diào)節(jié)因子,雌激素信號(hào)通路參與乳腺上皮細(xì)胞增殖和分化,特異性表達(dá)雌激素信號(hào)通路,增加細(xì)胞增殖率,提高了患乳腺癌的風(fēng)險(xiǎn)[11-12]。ER的表達(dá)量為乳腺癌治療和判斷預(yù)后的重要指標(biāo),因此了解ER信號(hào)的調(diào)控對(duì)于乳腺癌發(fā)病和預(yù)后機(jī)制的闡明至關(guān)重要。研究[13]表明,在ER陽(yáng)性乳腺癌組織中,ER mRNA的表達(dá)量明顯升高,而且ER突變率也明顯增加,ER對(duì)雌激素的敏感性增強(qiáng),誘發(fā)乳腺癌。研究[14]表明,ERs通過(guò)雌激素活化后引發(fā)的細(xì)胞內(nèi)級(jí)聯(lián)信號(hào)反應(yīng),包括胰島素樣生長(zhǎng)因子受體(IGFR)活化,產(chǎn)生基質(zhì)金屬蛋白酶,進(jìn)而使肝素結(jié)合樣生長(zhǎng)因子(HB-EGF)釋放。激活EGFR誘導(dǎo)MAPK(絲裂原活化蛋白激酶)信號(hào)通路。但是ER信號(hào)通路為何異常活化,機(jī)制尚不清楚。本研究顯示RunX表達(dá)與ER表達(dá)相關(guān),這進(jìn)一步支持了RunX2對(duì)乳腺癌發(fā)生發(fā)展具有重要影響作用。與此同時(shí),也提示,作為一種重要的轉(zhuǎn)錄因子,RunX2可能參與了ER的調(diào)節(jié),具體調(diào)節(jié)機(jī)制有待進(jìn)一步研究。
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RunX2 expression level and its association with clinical characteristics in patients with breast cancer
Hu Bin1,2,F(xiàn)an Chuling1,Xu Xiaojun3,et al
(1Basic Medical School of Anhui Medical University,Hefei 230032;
2Dept of Gastrointestinal Thyroid Breast Sugery,The First People's Hospital of Anqing,Anqing 246004;
3Dept of Breast Surgery,The First Affiliated Hospital of Anhui Medical University,Hefei 230022)
Objective To analyze the expression level of RunX2 gene in breast cancer patients and to investigate its relationship with patients'clinical characteristics and outcomes.Methods Tissue samples were selected from 75 breast cancer patients without radiation and chemotherapy before surgery.Immunohistochemistry was used to compare the expression level of RunX2 between cancer and para-carcinoma tissues.The relationship was analyzed between RunX2 expression and age,pathological type,postoperative stage,lymph node metastasis,tumor size,ER,PR,HER2 and ki67 expression and the overall survival rate.Results In 75 patients'tumor tissues,there were 44 cases with high expression of RunX2 in breast cancer,31 cases with low expression of RunX2.Meanwhile,in patients'adjacent tissues,there were only 23 cases of adjacent tissues with high RunX2 expression,the rest of 52 were low or negative RunX2 expression.The expression level of RunX2 in cancer tissues and para-carcinoma tissues had significantly difference(P<0.05).The expression level of RunX2 was not correlated with age,the postoperative stage,lymph node metastasis,pathologic types,PR and HER2 expression.But high RunX2 expression was significantly associated with ER and ki67 expression.Patients with high RunX2 expression had a poorer survival rate than those with negative or low expression.Conclusion The elevated RunX2 expression may be related to breast cancer ER phenotype and clinical outcomes.It provides further evidence that this gene might have an important,context-dependent role in breast cancer.
breast cancer;RunX2;estrogen receptor;clinical outcomes
R 365
A
1000-1492(2016)09-1356-04
時(shí)間:2016-8-1 14:07
http://www.cnki.net/kcms/detail/34.1065.R.20160801.1407.056.html
2016-06-08接收
國(guó)家自然科學(xué)基金(編號(hào):81302319)
1安徽醫(yī)科大學(xué)基礎(chǔ)醫(yī)學(xué)院,合肥 2300322安慶市第一人民醫(yī)院胃腸甲乳外科,安慶 2460043安徽醫(yī)科大學(xué)第一附屬醫(yī)院乳腺外科,合肥 230022
胡 濱,男,主治醫(yī)師,碩士研究生;李菲菲,女,副教授,碩士生導(dǎo)師,責(zé)任作者,E-mail:13965021937@163.com