Tao Wei, Ma Jun, Zheng Jian, Liu Xiaobai, Liu Yunhui, Ruan Xuelei, Shen Shuyuan, Shao Lianqi, Chen Jiajia, Xue Yixue
Department of Neurobiology, School of Life Sciences, China Medical University, Shenyang, China.
Key Laboratory of Cell Biology, Ministry of Public Health of China, China Medical University, Shenyang, China.
Front Oncol. 2020 May 27;10:613. doi: 10.3389/fonc.2020.00613. eCollection 2020.
Molecular-targeted therapy plays an important role in the combined treatment of breast cancer. Long noncoding RNA (LncRNA) plays a significant role in regulating breast cancer progression. The present study is to reveal the potential roles and molecular mechanism that the secretory carrier-associated membrane protein 1-transcript variant 2 (SCAMP1-TV2) has in breast. Cell Counting Kit-8 (CCK-8), RNA Immunoprecipitation (RIP), and RNA pull-down assays were employed to determine the interactions between SCAMP1-TV2 and Pumilio RNA binding family member 2 (PUM2). The luciferase reporter assays and chromatin immunoprecipitation (ChIP) assays were used to get to know the effect of human insulinoma-associated 1 (INSM1) directly on the SAM and SH3 domain containing 1 (SASH1) promoter. Silenced SCAMP1-TV2 inhibited the proliferation, migration, and invasion of breast cancer cells, and promoted cell apoptosis. Meanwhile, SCAMP1-TV2 downregulation decreased its binding to PUM2 and increased the binding of PUM2 to INSM1 messenger RNA (mRNA), thus promoting the degradation of INSM1 mRNA. Silencing INSM1 decreased its inhibitory effect on SASH1 transcription and inhibited the phosphatidylinositol 3-kinase (PI3K)/protein kinase B (AKT) signaling pathway. The xenograft tumor growth in a nude mice was significantly inhibited by the silencing of SCAMP1-TV2 in combination with the overexpression of PUM2. SCAMP1-TV2/PUM2/INSM1 pathway plays an important role in regulating the biological behavior of breast cancer cells.
分子靶向治疗在乳腺癌的联合治疗中发挥着重要作用。长链非编码RNA（LncRNA）在调节乳腺癌进展中起重要作用。本研究旨在揭示分泌载体相关膜蛋白1转录变体2（SCAMP1-TV2）在乳腺癌中的潜在作用和分子机制。采用细胞计数试剂盒-8（CCK-8）、RNA免疫沉淀（RIP）和RNA下拉实验来确定SCAMP1-TV2与Pumilio RNA结合家族成员2（PUM2）之间的相互作用。使用荧光素酶报告基因实验和染色质免疫沉淀（ChIP）实验来了解人胰岛素瘤相关蛋白1（INSM1）直接对含SAM和SH3结构域蛋白1（SASH1）启动子的影响。沉默SCAMP1-TV2可抑制乳腺癌细胞的增殖、迁移和侵袭，并促进细胞凋亡。同时，SCAMP1-TV2下调降低了其与PUM2的结合，并增加了PUM2与INSM1信使核糖核酸（mRNA）的结合，从而促进INSM1 mRNA的降解。沉默INSM1可降低其对SASH1转录的抑制作用，并抑制磷脂酰肌醇3激酶（PI3K）/蛋白激酶B（AKT）信号通路。联合沉默SCAMP1-TV2与过表达PUM2可显著抑制裸鼠体内异种移植瘤的生长。SCAMP1-TV2/PUM2/INSM1通路在调节乳腺癌细胞生物学行为中起重要作用。
