a Women's Hospital of Nanjing Medical University, Nanjing Maternity and Child Health Care Hospital, Nanjing, China.
b Reproductive Medical Center, Lianyungang Maternal and Child Health Hospital, Lianyungang, China.
Biochem Cell Biol. 2019 Aug;97(4):415-422. doi: 10.1139/bcb-2018-0301. Epub 2018 Nov 27.
A previous study by our group indicted that overexpression of bromodomain PHD-finger transcription factor (BPTF) occurs in lung adenocarcinoma, and is closely associated with advanced clinical stage, higher numbers of metastatic lymph nodes, the occurrence of distant metastasis, low histological grade, and poor prognosis. Down-regulation of BPTF inhibited lung adenocarcinoma cell proliferation and promoted lung adenocarcinoma cell apoptosis. The purpose of this study is to identify valuable microRNAs (miRNAs) that target BPTF to modulate lung adenocarcinoma cell proliferation. In our results, we found that miR-3666 was notably reduced in lung adenocarcinoma tissues and cell lines. Using an miR-3666 mimic, we discovered that cell proliferation, migration, and invasiveness were suppressed by miR-3666 overexpression, but these were all enhanced when the expression of miR-3666 was reduced. Moreover, bioinformatics analysis using the TargetScan database and miRanda software suggested a putative target site in BPTF 3'-UTR. Furthermore, using a luciferase reporter assay, we verified that miR-3666 directly targets the 3'-UTR of BPTF. Using Western blot we discovered that overexpression of miR-3666 negatively regulates the protein expression of BPTF. Finally, we identified that the PI3K-AKT and epilthelial-mesenchymal transition (EMT) signaling pathways were inhibited by miR-3666 overexpression in lung cancer cells. In conclusion, our data indicate that miR-3666 could play an essential role in cell proliferation, migration, and invasiveness by targeting BPTF and partly inhibiting the PI3K-AKT and EMT signaling pathways in human lung cancers.
先前本课题组的研究表明，溴结构域和 PHD 指状转录因子（Bromodomain PHD-finger transcription factor，BPTF）在肺腺癌中过表达，且与晚期临床分期、更多的转移性淋巴结、远处转移的发生、低组织学分级和不良预后密切相关。BPTF 的下调抑制肺腺癌细胞增殖并促进肺腺癌细胞凋亡。本研究旨在鉴定靶向 BPTF 的有价值的 microRNAs（miRNAs），以调节肺腺癌细胞增殖。我们的研究结果发现，miR-3666 在肺腺癌组织和细胞系中明显下调。通过使用 miR-3666 模拟物，我们发现 miR-3666 的过表达可抑制细胞增殖、迁移和侵袭，但降低 miR-3666 的表达会增强这些作用。此外，使用 TargetScan 数据库和 miRanda 软件进行生物信息学分析，提示 BPTF 3'-UTR 中有一个潜在的靶位。此外，通过荧光素酶报告基因检测证实，miR-3666 可直接靶向 BPTF 的 3'-UTR。通过 Western blot 检测发现，miR-3666 的过表达负调控 BPTF 的蛋白表达。最后，我们发现 miR-3666 过表达可部分抑制肺癌细胞中 PI3K-AKT 和上皮间质转化（epithelial-mesenchymal transition，EMT）信号通路。综上所述，我们的数据表明，miR-3666 可能通过靶向 BPTF 并部分抑制 PI3K-AKT 和 EMT 信号通路在人类肺癌中发挥重要作用，从而调节细胞增殖、迁移和侵袭。
