miR-630通过靶向MTDH抑制乳腺癌进程

周佽想，王辰龙，于安路，陈国强，赵　倩(上海交通大学医学院，上海200240)

miR-630通过靶向MTDH抑制乳腺癌进程

周佽想，王辰龙，于安路，陈国强，赵倩△
(上海交通大学医学院，上海200240)

目的:研究miRNA-630(miR-630)在乳腺癌中的表达水平及在乳腺癌发生发展中的功能。方法:采用反转录实时定量PCR方法对其在乳腺癌病人标本及乳腺癌细胞系中的表达进行检测;利用克隆形成实验、划痕实验、细胞迁移能力检测等方法对其在乳腺癌高转移细胞株MDA-MB-231及BT549中的功能进行研究;利用慢病毒感染方法构建稳定表达miR-630的MDA-MB-231细胞株，研究其在小鼠体内转移能力;通过生物信息学分析、萤光素酶报告基因分析和Western blot方法对miR-630的靶基因进行筛选和鉴定。结果: miR-630在乳腺癌病人癌组织以及乳腺癌细胞株中的表达显著降低;在MDA-MB-231 和BT549细胞中过表达miR-630显著抑制细胞的克隆形成能力及迁移侵袭能力。在体内实验中，稳定过表达miR-630抑制MDA-MB-231细胞的肺转移能力。最后，MTDH被鉴定为miR-630的靶基因，参与miR-630赋予细胞的各种功能。结论: miR-630通过靶向MTDH在乳腺癌的转移过程中发挥重要功能。

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