miR-630通過靶向MTDH抑制乳腺癌進程

周佽想，王辰龍，于安路，陳國強，趙　倩(上海交通大學(xué)醫(yī)學(xué)院，上海200240)

miR-630通過靶向MTDH抑制乳腺癌進程

周佽想，王辰龍，于安路，陳國強，趙倩△
(上海交通大學(xué)醫(yī)學(xué)院，上海200240)

目的:研究miRNA-630(miR-630)在乳腺癌中的表達水平及在乳腺癌發(fā)生發(fā)展中的功能。方法:采用反轉(zhuǎn)錄實時定量PCR方法對其在乳腺癌病人標(biāo)本及乳腺癌細胞系中的表達進行檢測;利用克隆形成實驗、劃痕實驗、細胞遷移能力檢測等方法對其在乳腺癌高轉(zhuǎn)移細胞株MDA-MB-231及BT549中的功能進行研究;利用慢病毒感染方法構(gòu)建穩(wěn)定表達miR-630的MDA-MB-231細胞株，研究其在小鼠體內(nèi)轉(zhuǎn)移能力;通過生物信息學(xué)分析、螢光素酶報告基因分析和Western blot方法對miR-630的靶基因進行篩選和鑒定。結(jié)果: miR-630在乳腺癌病人癌組織以及乳腺癌細胞株中的表達顯著降低;在MDA-MB-231 和BT549細胞中過表達miR-630顯著抑制細胞的克隆形成能力及遷移侵襲能力。在體內(nèi)實驗中，穩(wěn)定過表達miR-630抑制MDA-MB-231細胞的肺轉(zhuǎn)移能力。最后，MTDH被鑒定為miR-630的靶基因，參與miR-630賦予細胞的各種功能。結(jié)論: miR-630通過靶向MTDH在乳腺癌的轉(zhuǎn)移過程中發(fā)揮重要功能。

Repeated exposure to abuse drugs enhanced the cAMP response element-binding protein (CREB) -regulated cocaine-and amphetamine-regulated transcript (CART) expression in the nucleus accumbens (NAcc)，and these effects was known to contribute to the expression of behavioral sensitization.The present experiments investigated the contribution of microinjection of CART 55-102 into NAcc to the phosphorylation of CREB in this site which is known to participate in the Ca2 +influx and the cAMP-PKA signaling that are regulated responding to caffeine.Here we showed that CART 55-102 inhibited intracellular Ca2 +signal and attenuated caffeine-induced enhancement of depolarization-induced Ca2 +influx in cultured NAcc neurons.Repeated microinjection into the NAcc of CART 55-102 peptide (2.0 g/L per side) blocked the enhancement of p-CREB levels and extracellular signal-regulated kinase (ERK) phosphorylated kinase signaling produced by repeated oral administration of caffeine (30 mg/kg) in this sites at 5 d.Furthermore，the behavioral sensitization was exhibited in the rats given 5-day administration of caffeine following microinjection of saline，but absent in the rats with caffeine following microinjection of CART peptide.These results suggest that phosphorylation of CREB by caffeine in NAcc is blocked by CART 55-102 peptide due to the inhibition of Ca2 +influx and the ERK phosphorylation，and these effects may play a compensatory inhibitory role in expression of behavioral sensitization in the rats receiving microinjection of CART 55-102.

*［Foundation item］Supported by National Natural Science Foundation of China (No.81201035)

△Corresponding author E-mail: huzhenzhen@ncu.edu.cn

Blockade of caffeine-induced CREB phosphorylation by microinjection of CART peptide into nucleus accumbens is linked to inhibition of behavioral sensitization*

SUN Xi，ZHOU Xiao-yan，XU Fang-yun，HU Zhen-zhen△
(Pathophysiology，College of Medicine，Nanchang University，Nanchang 330006，China)

△E-mail: qzhao@shsmu.edu.cn