Medical Research Center, the Affiliated Hospital of Qingdao University, Qingdao, Shandong, China.
Department of Gastrointestinal Surgery, the Affiliated Hospital of Qingdao University, Qingdao, Shandong, China.
Ann N Y Acad Sci. 2021 Nov;1503(1):88-101. doi: 10.1111/nyas.14679. Epub 2021 Sep 3.
Circular RNA (circRNA) is implicated in many types of cancer; however, the expression and role of circRNAs in colorectal cancer (CRC) remains poorly understood. In this study, a circRNA microarray assay was performed to detect abnormally expressed circRNAs in CRC, and tissue arrays were used to determine the prognosis for CRC patients. Cell counting kit-8, clone formation, wound healing, and transwell assays were used to evaluate cell functions in vitro, and a mouse subcutaneous tumor model was designed for in vivo analysis. Autophagy was observed using confocal laser scanning and transmission electron microscopy. The expression of circRNA, miRNA, and mRNA was detected using qPCR; western blot, RNA pull-down assay, RNA immunoprecipitation, and dual luciferase assessment were applied for mechanistic studies. We found that circRNA_103948 expression is upregulated in CRC tissues, compared with adjacent normal tissues, and associated with poor prognosis. Knockdown of circRNA_103948 suppressed CRC both in vitro and in vivo. Mechanistically, circRNA_103948 could directly bind to miR-1236-3p and relieve suppression of the target TPT1. Furthermore, circRNA_103948 inhibited autophagy of CRC cells. Taken together, circRNA_103948 knockdown inhibited CRC cell growth by targeting miR-1236-3p/TPT1 axis-mediated autophagy. Thus, the circRNA_103948/miR-1236-3p/TPT1 axis affects CRC progression via modulation of autophagy.
环状 RNA（circRNA）参与多种类型的癌症；然而，circRNA 在结直肠癌（CRC）中的表达和作用仍知之甚少。在这项研究中，进行了 circRNA 微阵列分析以检测 CRC 中异常表达的 circRNAs，并使用组织阵列确定 CRC 患者的预后。细胞计数试剂盒-8、克隆形成、划痕愈合和 Transwell 测定用于体外评估细胞功能，设计了小鼠皮下肿瘤模型用于体内分析。使用共聚焦激光扫描和透射电子显微镜观察自噬。使用 qPCR 检测 circRNA、miRNA 和 mRNA 的表达；应用 Western blot、RNA 下拉测定、RNA 免疫沉淀和双荧光素酶评估进行机制研究。我们发现，circRNA_103948 在 CRC 组织中的表达上调，与相邻正常组织相比，与预后不良相关。circRNA_103948 的敲低在体外和体内均抑制 CRC。在机制上，circRNA_103948 可以直接与 miR-1236-3p 结合，从而缓解靶基因 TPT1 的抑制作用。此外，circRNA_103948 抑制 CRC 细胞的自噬。总之，circRNA_103948 的敲低通过靶向 miR-1236-3p/TPT1 轴介导的自噬抑制 CRC 细胞生长。因此，circRNA_103948/miR-1236-3p/TPT1 轴通过调节自噬影响 CRC 的进展。
