Department of General Surgery, the Fourth Affiliated Hospital of Harbin Medical University, No. 37 Yiyuan Street, Nangang District, Harbin, 150001, People's Republic of China.
Bio-Bank of Department of General Surgery, the Fourth Affiliated Hospital of Harbin Medical University, Harbin, 150001, People's Republic of China.
Mol Cancer. 2019 Mar 28;18(1):45. doi: 10.1186/s12943-019-1006-2.
Circular RNAs (circRNAs) are a novel type of noncoding RNAs and play important roles in tumorigenesis, including gastric cancer (GC). However, the functions of most circRNAs remain poorly understood. In our study, we aimed to investigate the functions of a new circRNA circ-DONSON in GC progression.
The expression of circ-DONSON in gastric cancer tissues and adjacent normal tissues was analyzed by bioinformatics method, qRT-PCR, Northern blotting and in situ hybridization (ISH). The effects of circ-DONSON on GC cell proliferation, apoptosis, migration and invasion were measured by using CCK8, colony formation, EdU, immunofluorescence (IF), FACS and Transwell assays. qRT-PCR and Western blotting were utilized to validate how circ-DONSON regulates SOX4 expression. ChIP, DNA fluorescence in situ hybridization (DNA-FISH) and DNA accessibility assays were used to investigate how circ-DONSON regulates SOX4 transcription. The interaction between circ-DONSON and NURF complex was evaluated by mass spectrum, RNA immunoprecipitation (RIP), pulldown and EMSA assays. Xenograft mouse model was used to analyze the effect of circ-DONSON on GC growth in vivo.
Elevated expression of circ-DONSON was observed in GC tissues and positively associated with advanced TNM stage and unfavorable prognosis. Silencing of circ-DONSON significantly suppressed the proliferation, migration and invasion of GC cells while promoting apoptosis. circ-DONSON was localized in the nucleus, recruited the NURF complex to SOX4 promoter and initiated its transcription. Silencing of the NURF complex subunit SNF2L, BPTF or RBBP4 similarly attenuated GC cell growth and increased apoptosis. circ-DONSON knockdown inhibited GC growth in vivo.
circ-DONSON promotes GC progression through recruiting the NURF complex to initiate SOX4 expression.
环状 RNA（circRNAs）是一种新型的非编码 RNA，在肿瘤发生中发挥重要作用，包括胃癌（GC）。然而，大多数 circRNAs 的功能仍知之甚少。在我们的研究中，我们旨在研究一种新的 circRNA circ-DONSON 在 GC 进展中的作用。
通过生物信息学方法、qRT-PCR、Northern blot 和原位杂交（ISH）分析 circ-DONSON 在胃癌组织和相邻正常组织中的表达。通过 CCK8、集落形成、EdU、免疫荧光（IF）、FACS 和 Transwell 测定测定 circ-DONSON 对 GC 细胞增殖、凋亡、迁移和侵袭的影响。qRT-PCR 和 Western blot 用于验证 circ-DONSON 如何调节 SOX4 表达。ChIP、DNA 荧光原位杂交（DNA-FISH）和 DNA 可及性测定用于研究 circ-DONSON 如何调节 SOX4 转录。通过质谱、RNA 免疫沉淀（RIP）、下拉和 EMSA 测定评估 circ-DONSON 与 NURF 复合物的相互作用。利用异种移植小鼠模型分析 circ-DONSON 对体内 GC 生长的影响。
在 GC 组织中观察到 circ-DONSON 的表达升高，并且与晚期 TNM 分期和不良预后呈正相关。circ-DONSON 沉默显着抑制 GC 细胞的增殖、迁移和侵袭，同时促进凋亡。circ-DONSON 定位于细胞核内，募集 NURF 复合物到 SOX4 启动子并启动其转录。沉默 NURF 复合物亚基 SNF2L、BPTF 或 RBBP4 同样减弱 GC 细胞生长并增加凋亡。circ-DONSON 敲低抑制体内 GC 生长。
circ-DONSON 通过募集 NURF 复合物启动 SOX4 表达来促进 GC 进展。
