張洋，董理，孫源博，李文媛，王瑩，孫平，于偉光

(1牡丹江醫(yī)學(xué)院，黑龍江牡丹江 157011；2牡丹江醫(yī)學(xué)院紅旗醫(yī)院)

下調(diào)HMGA1對(duì)乳腺癌MCF7細(xì)胞增殖和侵襲能力的影響及機(jī)制

張洋1，董理2，孫源博2，李文媛1，王瑩1，孫平1，于偉光2

(1牡丹江醫(yī)學(xué)院，黑龍江牡丹江 157011；2牡丹江醫(yī)學(xué)院紅旗醫(yī)院)

目的觀察下調(diào)高遷移率族蛋白A1(HMGA1)對(duì)乳腺癌MCF7細(xì)胞增殖和侵襲能力的影響，并探討其機(jī)制。方法選擇人乳腺癌MCF7細(xì)胞，將其分為siRNA對(duì)照組、siRNA-HMGA1組、miR對(duì)照組和miR-24-3p組，分別轉(zhuǎn)染siRNA對(duì)照慢病毒、siRNA-HMGA1慢病毒、miR對(duì)照慢病毒和miR-24-3p慢病毒。采用Western boltting法檢測(cè)未轉(zhuǎn)染MCF7、正常乳腺上皮細(xì)胞株(HMEC hTERT)及siRNA對(duì)照組、siRNA-HMGA1組細(xì)胞HMGA1蛋白，實(shí)時(shí)熒光定量PCR法檢測(cè)miR對(duì)照組和miR-24-3p組細(xì)胞HMGA1、miR-142-3p mRNA，MTT法和Transwell法檢測(cè)4組細(xì)胞增殖活力和侵襲能力，熒光素酶報(bào)告基因分析驗(yàn)證HMGA1與miR-142-3p靶向關(guān)系。結(jié)果MCF7、HMEC hTERT細(xì)胞中HMGA1蛋白相對(duì)表達(dá)量分別為0.574±0.075、0.234±0.099，兩者相比P<0.01。siRNA-HMGA1組、siRNA對(duì)照組HMGA1蛋白相對(duì)表達(dá)量分別為0.141±0.051、0.651±0.136，兩組相比P<0.01。miR-142-3p組、miR對(duì)照組HMGA1 mRNA相對(duì)表達(dá)量分別為0.135±0.046、0.604±0.156，miR-142-3 mRNA相對(duì)表達(dá)量分別為1.128±0.174、0.263±0.116，兩者相比P均<0.01。MCF7細(xì)胞中HMGA1 mRNA、miR-142-3p mRNA表達(dá)呈負(fù)相關(guān)(r=-0.259，P=0.021)。siRNA-HMGA1組、siRNA對(duì)照組細(xì)胞增殖活力分別為0.535±0.066、1.160±0.125，穿膜細(xì)胞數(shù)分別為(32.05±9.33)、(71.68±14.39)個(gè)，兩者相比P均<0.01。miR-142-3p組、miR對(duì)照組細(xì)胞增殖活力分別為0.362±0.121、1.083±0.139，穿膜細(xì)胞數(shù)分別為(21.52±6.64)、(46.74±7.82)個(gè)，兩組相比P均<0.01。miR-142-3p組、miR對(duì)照組野生型HMGA1 3′-UTR熒光素酶活性分別為0.668±0.074、1.000±0.000，兩組相比P<0.01。結(jié)論下調(diào)HMGA1乳腺癌MCF7細(xì)胞增殖和侵襲能力增強(qiáng)，其機(jī)制可能與HMGA1可靶向反向調(diào)控miR-142-3p有關(guān)。

高遷移率族蛋白A1；微小RNA 142-3p；乳腺腫瘤；細(xì)胞增殖；細(xì)胞侵襲

乳腺癌是一種常見(jiàn)的惡性腫瘤，是全球女性因癌癥導(dǎo)致死亡的首要原因。乳腺癌高病死率主要原因?yàn)槟[瘤轉(zhuǎn)移，而腫瘤轉(zhuǎn)移相關(guān)基因已被證實(shí)參與腫瘤細(xì)胞增殖，因此，篩選鑒定腫瘤細(xì)胞增殖和轉(zhuǎn)移的生物標(biāo)志物，對(duì)乳腺癌臨床治療具有重要意義[1]。高遷移率族蛋白A1(HMGA1)是一種染色質(zhì)相關(guān)蛋白質(zhì)。最近研究表明HMGA1為多種惡性腫瘤的致癌基因[2]，其在乳腺癌[3]、胃癌[4]、卵巢癌[5]、非小細(xì)胞肺癌[6]、甲狀腺癌[7]中表達(dá)上調(diào)，并促進(jìn)腫瘤細(xì)胞增殖、侵襲、遷移，其高表達(dá)與胃癌[4]和非小細(xì)胞肺癌[6]患者的預(yù)后呈負(fù)相關(guān)。本研究前期通過(guò)TargetScan軟件發(fā)現(xiàn)與3′非編碼區(qū)(3′-UTR)HMGA1序列相匹配microRNAs為miR-142-3p，而miR-142-3p已被證實(shí)可作為多種腫瘤的抑癌基因。研究表明,胰腺癌[8]、乳腺癌[9]和結(jié)腸癌[10]中miR-142-3p表達(dá)下調(diào)，并抑制腫瘤增殖、遷移和侵襲。但在乳腺癌細(xì)胞中HMGA1的生物學(xué)作用及對(duì)miR-142-3p的靶向調(diào)控目前尚不明確。2011年10月～2016年2月,本研究觀察了下調(diào)HMGA1對(duì)乳腺癌MCF7細(xì)胞增殖和侵襲能力的影響，并探討其對(duì)miR-142-3p的靶向調(diào)控作用，為臨床乳腺癌治療提供新的靶點(diǎn)。

1 材料與方法

1.1 實(shí)驗(yàn)試劑與儀器 siRNA-HMGA1慢病毒(piLenti-siRNA-HMGA1)、siRNA對(duì)照慢病毒(piLenti-siRNA-GFP)、miR-142-3p慢病毒(Lenti hsa-miR-142-3p)、miR對(duì)照慢病毒(pLenti-Ⅲ-miR-Blank)均購(gòu)于美國(guó)ABM公司；HMGA1、miR-142-3p、內(nèi)參U6、GAPDH引物由美國(guó)Ambion公司合成；雙熒光素酶報(bào)告試劑盒購(gòu)自美國(guó)Promega公司；四氮唑藍(lán)(MTT)、二甲基亞砜(DMSO)、HMGA1一抗購(gòu)自美國(guó)Sigma公司；microRNA PCR Kit試劑盒購(gòu)自美國(guó)Exiqon公司；TRIzol提取液購(gòu)自美國(guó)Invitrogen公司。CO2培養(yǎng)箱(日本三洋公司)；超凈臺(tái)(蘇州蘇凈安泰公司)；凝膠成像系統(tǒng)(北京六一公司)。

1.2 細(xì)胞來(lái)源及培養(yǎng)方法 人乳腺癌細(xì)胞株(MCF7)和正常乳腺上皮細(xì)胞株(HMEC hTERT)購(gòu)于美國(guó)Sigma公司，并采用含10%胎牛血清的PRMI1640培養(yǎng)基培養(yǎng)，置于37 ℃、5% CO2培養(yǎng)箱內(nèi)培養(yǎng)，3～4 d消化傳代，取生長(zhǎng)狀態(tài)良好的細(xì)胞用于實(shí)驗(yàn)。

1.3 HMGA1、miR-142-3p轉(zhuǎn)染方法 取對(duì)數(shù)生長(zhǎng)期MCF7細(xì)胞，將其分為siRNA對(duì)照組、siRNA-HMGA1組、miR對(duì)照組和miR-24-3p組，鋪于6孔板中，1 d后進(jìn)行轉(zhuǎn)染。各組每孔取37 ℃預(yù)熱無(wú)血清DMEM/F12培養(yǎng)基稀釋后分別加入2 μL siRNA對(duì)照慢病毒、siRNA-HMGA1慢病毒、miR對(duì)照慢病毒和miR-24-3p慢病毒。將培養(yǎng)板置于37 ℃的CO2培養(yǎng)箱中培養(yǎng)72 h后用于進(jìn)一步實(shí)驗(yàn)。

1.4 細(xì)胞HMGA1蛋白檢測(cè) 采用Western boltting法。取MCF7、HMEC hTERT及siRNA對(duì)照組和siRNA-HMGA1組細(xì)胞，應(yīng)用10%SDS-聚丙烯酰胺凝膠電泳提取蛋白質(zhì)提取物，轉(zhuǎn)移到PVDF膜，封閉后加入一抗HMGA1抗體(1∶1 000)或GADPH(1∶5 000)，加入二抗(1∶2 000)孵育2 h，TBS洗凈，應(yīng)用顯色液顯示后行吸光度分析。以GADPH做校正得到積分光密度相對(duì)比值來(lái)計(jì)算細(xì)胞HMGA1蛋白相對(duì)表達(dá)量。

1.5 細(xì)胞HMGA1、miR-142-3p mRNA檢測(cè) 采用實(shí)時(shí)熒光定量PCR法。取miR對(duì)照組和miR-24-3p組細(xì)胞，應(yīng)用TRIzol提取總RNA，通過(guò)逆轉(zhuǎn)錄合成cDNA，根據(jù)說(shuō)明書(shū)通過(guò)SYBR Green系統(tǒng)進(jìn)行實(shí)時(shí)熒光定量。HMGA1引物序列：5′-AGGAAAAGGACGGCACTGAGAA-3′；5′-CCCCGAGGTCTCTTAGGTGTTGG-3′。GAPDH引物序列：5′-ACAGTCAGCCGCATCTTCTT-3′；5′-GACAAGCTTCCCGTTCTCAG-3′。miR-142-3p應(yīng)用Mirvana qRT-PCR miRNA檢測(cè)試劑盒進(jìn)行檢測(cè)。miR-142-3p引物序列：5′-GTCGTATCCAGTGCAGGG-3′；5′-CGACGTGTAGTGTTTCCTA-3′；U6引物序列：5′-CGAGCACAGAATCGCTTCA-3′；5′-CTCGCTTCGGCAGCACATAT-3′。反應(yīng)條件：預(yù)變性95 ℃ 60 s，95 ℃ 5 s，60 ℃ 31 s共40 個(gè)循環(huán)；95 ℃ 15 s，60 ℃ 30 s，95 ℃15 s。以GAPDH為內(nèi)參，采用2-ΔΔCt計(jì)算HMGA1、miR-142-3p mRNA相對(duì)表達(dá)量。

1.6 細(xì)胞增殖能力觀察 將上述4組細(xì)胞接種于96孔板，每孔2×103個(gè)細(xì)胞，培養(yǎng)6 d。在細(xì)胞生長(zhǎng)檢測(cè)時(shí)間點(diǎn)，每孔加入20 μL 5 mg/mL的MTT培養(yǎng)2 h，丟棄培養(yǎng)液，PBS沖洗，每孔加入100 mL的DMSO，在570 nm波長(zhǎng)測(cè)定吸光度值，檢測(cè)細(xì)胞增殖活力[11]。

1.7 細(xì)胞侵襲能力觀察 應(yīng)用Transwell法觀察細(xì)胞侵襲能力，分別取上述4組(8～10)×104個(gè)細(xì)胞加入到基質(zhì)膠的上室，600 μL RPMI1640培養(yǎng)液注入下室。收集細(xì)胞后PBS沖洗和固定，0.1%結(jié)晶紫染色，拍照及顯微鏡下計(jì)數(shù)細(xì)胞個(gè)數(shù)。

1.8 熒光素酶報(bào)告基因分析驗(yàn)證HMGA1與miR-142-3p靶向關(guān)系 采用熒光素酶報(bào)告基因分析。從人基因組DNA中克隆HMGA1 3′-UTR，插入XhoⅠ與NotⅠ酶切位點(diǎn)之間，進(jìn)行psiCHECK-2熒光素酶基因報(bào)告，通過(guò)測(cè)序驗(yàn)證野生型和突變型的插入序列[12]，構(gòu)建含有野生型或突變HMGA1 3′-UTR序列靶位點(diǎn)熒光素酶報(bào)告基因載體。分別取miR對(duì)照組和miR-24-3p組細(xì)胞，接種在24孔板中。根據(jù)說(shuō)明書(shū)用雙熒光素酶報(bào)告系統(tǒng)檢測(cè)熒光素酶活性。

2 結(jié)果

2.1 MCF7、HMEC hTERT細(xì)胞中HMGA1蛋白表達(dá)比較 MCF7、HMEC hTERT細(xì)胞中HMGA1蛋白相對(duì)表達(dá)量分別為0.574±0.075、0.234±0.099，兩者相比P<0.01。

2.2 siRNA-HMGA1組、siRNA對(duì)照組HMGA1蛋白表達(dá)比較 siRNA-HMGA1組、siRNA對(duì)照組HMGA1蛋白相對(duì)表達(dá)量分別為0.141±0.051、0.651±0.136，兩組相比P<0.01。

2.3 miR-142-3p組、miR對(duì)照組HMGA1 mRNA表達(dá)比較 miR-142-3p組、miR對(duì)照組HMGA1 mRNA相對(duì)表達(dá)量分別為0.135±0.046、0.604±0.156，miR-142-3 mRNA相對(duì)表達(dá)量分別為1.128±0.174、0.263±0.116，兩者相比P均<0.01。

2.4 MCF7細(xì)胞中HMGA1 mRNA與miR-142-3p mRNA的關(guān)系 MCF7細(xì)胞中HMGA1 mRNA、miR-142-3p mRNA兩者相對(duì)表達(dá)量呈負(fù)相關(guān)(r=-0.259，P=0.021)。

2.5 siRNA-HMGA1組、siRNA對(duì)照組細(xì)胞增殖、侵襲能力比較 siRNA-HMGA1組、siRNA對(duì)照組細(xì)胞增殖活力分別為0.535±0.066、1.160±0.125，穿膜細(xì)胞數(shù)分別為(32.05±9.33)、(71.68±14.39)個(gè)，兩者相比P均<0.01。

2.6 miR-142-3p組、miR對(duì)照組細(xì)胞增殖、侵襲能力比較 miR-142-3p組、miR對(duì)照組細(xì)胞增殖活力分別為0.362±0.121、1.083±0.139，穿膜細(xì)胞數(shù)分別為(21.52±6.64)、(46.74±7.82)個(gè)，兩組相比P均<0.01。

2.7 HMGA1與miR-142-3p靶向關(guān)系驗(yàn)證結(jié)果 miR-142-3p組、miR對(duì)照組野生型HMGA1 3′-UTR熒光素酶活性分別為0.668±0.074、1.000±0.000，兩組相比P<0.01。miR-142-3p組、miR對(duì)照組突變型HMGA1 3′-UTR熒光素酶活性分別為1.020±0.031、1.000±0.000，兩組相比P﹥0.05。

3 討論

高遷移率族蛋白家族(HMG)是一系列染色質(zhì)結(jié)構(gòu)調(diào)控蛋白家族，在腫瘤發(fā)生發(fā)展中發(fā)揮關(guān)鍵作用，參與多種生物學(xué)進(jìn)程，包括細(xì)胞周期調(diào)控、細(xì)胞增殖和遷移等[3]。HMGA1為HMGA家族的主要成員，HMGA1蛋白包括HMGA1a和HMGA1b，主要通過(guò)綁定位于多種基因啟動(dòng)子和增強(qiáng)子區(qū)域A/T-rich DNA序列，通過(guò)蛋白質(zhì)-蛋白質(zhì)作用調(diào)節(jié)染色質(zhì)結(jié)構(gòu)，其失調(diào)可能會(huì)導(dǎo)致染色體不穩(wěn)定[5]。HMGA1激活I(lǐng)Rb啟動(dòng)子，促進(jìn)參與胰島素抵抗(IR)表達(dá)缺失。HMGA1能夠調(diào)節(jié)細(xì)胞周期蛋白E2的活動(dòng)，轉(zhuǎn)移Yes相關(guān)蛋白(YAP)至細(xì)胞核，進(jìn)而增強(qiáng)細(xì)胞運(yùn)動(dòng)和侵襲性[13]。HMGA1高表達(dá)已被證明是腫瘤細(xì)胞的標(biāo)志物，在一些腫瘤疾病的診斷和預(yù)后評(píng)估中具有重要的價(jià)值。HMGA1在腫瘤細(xì)胞通過(guò)Wnt/β-catenin和Pin1/mutant p53信號(hào)通路維持腫瘤干細(xì)胞和腫瘤轉(zhuǎn)移特性[14,15]。HMGA1蛋白質(zhì)已被證明是不同來(lái)源的細(xì)胞致瘤相關(guān)的“樞紐蛋白”，在促進(jìn)細(xì)胞增殖和遷移中發(fā)揮重要作用[16]。HMGA1基因在人類(lèi)乳腺癌中過(guò)度表達(dá)，敲除乳腺癌組織中HMGA1能顯著減少錨定依賴性生長(zhǎng)及移植瘤形成，但HMGA1在乳腺癌的生物學(xué)作用機(jī)制尚不明確。

本研究發(fā)現(xiàn)HMGA1在乳腺癌MCF7細(xì)胞中表達(dá)較正常乳腺細(xì)胞增高，表明HMGA1可能參與乳腺癌的發(fā)生發(fā)展過(guò)程。本研究結(jié)果表明siRNA-HMGA1組較siRNA對(duì)照組HMGA1蛋白表達(dá)低，證實(shí)siRNA-HMGA1慢病毒有效沉默HMGA1表達(dá)。進(jìn)一步研究發(fā)現(xiàn)，siRNA-HMGA1組較siRNA對(duì)照組細(xì)胞增殖活力低且穿膜細(xì)胞數(shù)少。這表明下調(diào)HMGA1表達(dá)可抑制MCF7細(xì)胞增殖活力和侵襲能力，反向證實(shí)HMGA1能夠通過(guò)促進(jìn)乳腺癌細(xì)胞增殖和侵襲，在乳腺癌發(fā)病過(guò)程中發(fā)揮重要作用。

microRNAs是非編碼單鏈RNA分子(22個(gè)核苷酸的長(zhǎng)度)，在轉(zhuǎn)錄后通過(guò)與靶基因mRNA的3′-UTR發(fā)生堿基配對(duì)，引起靶基因mRNA的降解或者抑制其翻譯[8]，在腫瘤發(fā)展過(guò)程中發(fā)揮重要調(diào)控作用。為探討HMGA1潛在的靶點(diǎn)microRNA，本研究構(gòu)建了含有野生型或突變3′-UTR HMGA1序列靶位點(diǎn)熒光素酶報(bào)告基因載體，結(jié)果發(fā)現(xiàn)miR-142-3p組較miR對(duì)照組野生型HMGA1 3′-UTR熒光素酶活性低，表明miR-142-3p高表達(dá)顯著降低野生型HMGA1 3′-UTR熒光素酶活性。HMGA1在MCF7細(xì)胞表達(dá)顯著上調(diào)，且MCF7細(xì)胞中HMGA1 mRNA與miR-142-3p mRNA表達(dá)呈負(fù)相關(guān)，進(jìn)一步證實(shí)miR-142-3p是HMGA1的直接靶基因，HMGA1反向調(diào)控miR-142-3p發(fā)揮作用。miR-142-3p可作為一個(gè)獨(dú)立的腫瘤抑制因子，在胰腺癌、乳腺癌和結(jié)腸癌[8～10]等多種腫瘤組織中表達(dá)下調(diào)，并抑制腫瘤細(xì)胞增殖、遷移和侵襲。本研究結(jié)果顯示miR-142-3p組較miR對(duì)照組細(xì)胞增殖活力低且穿膜細(xì)胞數(shù)少，證實(shí)miR-142-3p可抑制MCF7細(xì)胞增殖活力和侵襲能力，這與以往miR-142-3p在其他腫瘤中的作用相一致[17]。因此我們推測(cè)HMGA1靶向反向調(diào)節(jié)miR-142-3p促進(jìn)腫瘤細(xì)胞增殖和侵襲，這可能是HMGA1在乳腺癌中作用機(jī)制之一。

綜上所述，下調(diào)HMGA1乳腺癌MCF7細(xì)胞增殖和侵襲能力增強(qiáng)，其機(jī)制可能與HMGA1可靶向反向調(diào)控miR-142-3p有關(guān)。

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[2] De Martino M, Forzati F, Arra C, et al. HMGA1-pseudogenes and cancer[J]. Oncotarget, 2016,7(19): 28724-28735.

[3] Huang R, Huang D, Dai W, et al. Overexpression of HMGA1 correlates with the malignant status and prognosis of breast cancer[J]. Mol Cell Biochem, 2015,404(1-2):251-257.

[4] Jun KH, Jung JH, Choi HJ, et al. HMGA1/HMGA2 protein expression and prognostic implications in gastric cancer[J]. Int J Surg, 2015,24(Pt A):39-44.

[5] Kim DK, Seo EJ, Choi EJ, et al. Crucial role of HMGA1 in the self-renewal and drug resistance of ovarian cancer stem cells[J]. Exp Mol Med, 2016,48(e255):1-11.

[6] Lin SY, Peng F. Association of SIRT1 and HMGA1 expression in non-small cell lung cancer[J]. Oncol Lett, 2016,11(1):782-788.

[7] Zhong J, Liu C, Chen YJ, et al. The association between S100A13 and HMGA1 in the modulation of thyroid cancer proliferation and invasion[J]. J Transl Med, 2016,14(80):1-13.

[8] Mackenzie TN, Mujumdar N, Banerjee S, et al. Triptolide induces the expression of miR-142-3p: a negative regulator of heat shock protein 70 and pancreatic cancer cell proliferation[J]. Mol Cancer Ther, 2013,12(7):1266-1275.

[9] Schwickert A, Weghake E, Bruggemann K, et al. microRNA miR-142-3p inhibits breast cancer cell invasiveness by synchronous targeting of WASL, integrin alpha V, and additional cytoskeletal elements[J]. PLoS One, 2015,10(12):e0143993.

[10] Shen WW, Zeng Z, Zhu WX, et al. MiR-142-3p functions as a tumor suppressor by targeting CD133, ABCG2, and Lgr5 in colon cancer cells[J]. J Mol Med (Berl), 2013,91(8):989-1000.

[11]馬素珍,潘曉麗,張方方,等.TRIM28在結(jié)直腸癌組織中的表達(dá)及其對(duì)癌細(xì)胞增殖、遷移能力的影響[J].山東醫(yī)藥,2017,57(10):28-30.

[12] Zhang X, Tao T, Liu C, et al. Downregulation of miR-195 promotes prostate cancer progression by targeting HMGA1[J]. Oncol Rep, 2016,36(1):376-382.

[13] Pegoraro S, Ros G, Ciani Y, et al. A novel HMGA1-CCNE2-YAP axis regulates breast cancer aggressiveness[J]. Oncotarget, 2015,6(22):19087-19101.

[14] Liu K, Zhang C, Li T, et al. Let-7a inhibits growth and migration of breast cancer cells by targeting HMGA1[J]. Int J Oncol, 2015,46(6):2526-2534.

[15] Zhou WB, Zhong CN, Luo XP, et al. miR-625 suppresses cell proliferation and migration by targeting HMGA1 in breast cancer[J]. Biochem Biophys Res Commun, 2016,470(4):838-844.

[16] Sumter TF, Xian L, Huso T, et al. The high mobility group A1 (HMGA1) transcriptome in cancer and development[J]. Curr Mol Med, 2016,16(4):353-393.

[17] Cao XC, Yu Y, Hou LK, et al. miR-142-3p inhibits cancer cell proliferation by targeting CDC25C[J]. Cell Prolif, 2016,49(1):58-68.

Effectsofdown-regulationofHMGA1onproliferationandinvasionofbreastcancerMCF7cells

ZHANGYang1,DONGLi,SUNYuanbo,LIWenyuan,WANGYing,SUNPing,YUWeiguang

(1MudanjiangMedicalCollege,Mudanjiang157011,China)

ObjectiveTo investigate the effects of the down-regulation of high mobility group protein A1 (HMGA1) on the proliferation and invasion of breast cancer MCF7 cells and its mechanism.MethodsThe human breast cancer cell line (MCF7) was divided into four groups: siRNA control group, siRNA-HMGA1 group, miR control group, and miR-24-3p group; MCF7 cells in the above groups were transfected with siRNA control lentivirus, siRNA-HMGA1 lentivirus, miR control lentivirus and miR-24-3p lentivirus, respectively. The protein expression of HMGA1 was detected in MCF7 cells, normal breast epithelial cell line (HMEC hTERT), siRNA control group, and siRNA-HMGA1 group by using Western blotting; the HMGA1 and miR-142-3p mRNA expression and its correlation was detected in the miR control group and miR-24-3p group by real-time quantitative PCR; the cell proliferation and invasion were detected in the four groups by MTT and Transwell assay; Luciferase reporter experiment was used to verify the target relationship between HMGA1 and miR-142-3p.ResultsHMGA1 protein expression in MCF7 cells was 0.574±0.075, which was significantly higher than that of HMEC hTERT cells (0.234±0.099) (P<0.05), and the expression of HMGA1 in siRNA-HMGA1 group (0.141±0.051) was lower than that of siRNA group (0.651±0.136) (P<0.05); HMGA1 mRNA expression in the miR-142-3p group was lower than that of the miR control group (0.135±0.046 vs 0.604±0.156), and the miR-142-3 mRNA expression was higher than that of the miR control group (1.128±0.174 vs 0.263±0.116) (allP<0.01); the expression of HMGA1 mRNA and miR-142-3p mRNA was negatively correlated (r=0.259,P<0.05); the cell proliferation in the siRNA-HMGA1 group was lower than that of the control group (0.535±0.066 vs 1.160± 0.125), transmembrane cell number was also lower than that of the siRNA group (32.05±9.33 vs 71.68±14.39) (P<0.05); the cell proliferation ability of miR-142-3p group was lower than that of the miR group (0.362±0.121 vs 1.083±0.139), and the transmembrane cell number was also lower than that of the miR group (21.52±6.64 vs 46.74±7.82) (P<0.05); in the miR-142-3p group and the miR control group, the Dual luciferase reporter assay demonstrated that the HMGA1 3′-UTR luciferase activity in wild-type was 0.668±0.074 and 1.000±0.000, respectively (P<0.01).ConclusionThe down-regulation of HMGA1 expression can promote the proliferation and invasion of breast cancer cells by reversely regulating miR-142-3p expression.

high mobility group protein A1; microRNA-142-3p; breast carcinoma; cell proliferation; cell invasion

10.3969/j.issn.1002-266X.2017.38.005

R735

A

1002-266X(2017)38-0015-04

國(guó)家自然科學(xué)基金資助項(xiàng)目(81371362)；黑龍江省自然科學(xué)基金項(xiàng)目(H201377)。

張洋(1987-)，女，博士，講師，主要研究方向?yàn)槟[瘤轉(zhuǎn)移機(jī)制。E-mail: 978619420@qq.com

于偉光(1987-)，男，博士，主治醫(yī)師，主要研究方向?yàn)槟[瘤轉(zhuǎn)移機(jī)制。E-mail: Yingwang770224@163.com

2017-03-29)