Department of Gastrointestinal and Anorectal Surgery, The Third Central Hospital of Tianjin, Tianjin Key Laboratory of Extracorporeal Life Support for Critical Diseases, Artificial Cell Engineering Technology Research Center, Tianjin Institute of Hepatobiliary Disease, Tianjin, China.
J Biochem Mol Toxicol. 2024 Aug;38(8):e23772. doi: 10.1002/jbt.23772.
Colorectal cancer (CRC) is the leading cause of cancer-related death globally. Circular RNA circCOL5A1 plays an oncogene function in a variety of tumors. However, the function of circCOL5A1 in CRC is still unknown. Here, we aimed to elucidate the function and mechanism of circCOL5A1 in CRC. The correlation between circCOL5A1 and CRC clinicopathological was assessed through chi-square. The relevance between circCOL5A1 and CRC patient survival time was evaluated by Kaplan-Meier analysis. The expressions of circCOL5A1 in CRC were determined via quantitative real-time PCR. The function of circCOL5A1 in CRC was analyzed with Cell Counting Kit-8, EdU assay, Transwell, detection of reactive oxygen species and Fe levels, and Western blot analysis. Moreover, the mechanism of circCOL5A1 was determined by dual-luciferase reporter assay, RNA immunoprecipitation, and RNA pull-down. Finally, the role of circCOL5A1 in vivo was elucidated through a mouse xenograft model, hematoxylin-eosin staining, and immunohistochemistry. CircCOL5A1 expression was increased in CRC, and increased circCOL5A1 levels were related to TNM stage, lymph node metastasis, distant metastasis, and tumor differentiation in CRC patients, and CRC patients with high circCOL5A1 levels had a low overall survival rate. For the circCOL5A1 function in CRC, we found that circCOL5A1 knockdown weakened CRC cell proliferation and invasion, and enhanced cell ferroptosis. For the circCOL5A1 mechanism in CRC, we further confirmed that circCOL5A1 bound to miR-1287-5p, miR-1287-5p bound to SLC7A11. SLC7A11 was negatively interrelated to miR-1287-5p and was positively interrelated to circCOL5A1 in CRC tissues. Furthermore, interfering circCOL5A1 decreased SLC7A11 expression, and this trend was abolished through miR-1287-5p cotransfection. Rescue assays further demonstrated that circCOL5A1 knockdown alleviated CRC cell malignant phenotype via miR-1287-5p/SLC7A11. Moreover, interference with circCOL5A1 reduced CRC growth in vivo. CircCOL5A1 functioned as an oncogene in CRC via miR-1287-5p/SLC7A11.
结直肠癌（CRC）是全球癌症相关死亡的主要原因。环状 RNA circCOL5A1 在多种肿瘤中发挥致癌基因功能。然而，circCOL5A1 在 CRC 中的功能仍不清楚。在这里，我们旨在阐明 circCOL5A1 在 CRC 中的功能和机制。通过卡方检验评估 circCOL5A1 与 CRC 临床病理的相关性。通过 Kaplan-Meier 分析评估 circCOL5A1 与 CRC 患者生存时间的相关性。通过实时定量 PCR 确定 CRC 中 circCOL5A1 的表达。通过细胞计数试剂盒-8、EdU 测定、Transwell 测定、活性氧和铁水平检测以及 Western blot 分析分析 circCOL5A1 在 CRC 中的功能。此外，通过双荧光素酶报告基因检测、RNA 免疫沉淀和 RNA 下拉确定 circCOL5A1 的机制。最后，通过小鼠异种移植模型、苏木精-伊红染色和免疫组织化学阐明 circCOL5A1 在体内的作用。CRC 中 circCOL5A1 的表达增加，CRC 患者中 circCOL5A1 水平升高与 TNM 分期、淋巴结转移、远处转移和肿瘤分化有关，circCOL5A1 水平较高的 CRC 患者总生存率较低。关于 circCOL5A1 在 CRC 中的功能，我们发现 circCOL5A1 敲低减弱了 CRC 细胞的增殖和侵袭，并增强了细胞铁死亡。关于 circCOL5A1 在 CRC 中的机制，我们进一步证实 circCOL5A1 与 miR-1287-5p 结合，miR-1287-5p 与 SLC7A11 结合。SLC7A11 在 CRC 组织中与 miR-1287-5p 呈负相关，与 circCOL5A1 呈正相关。此外，干扰 circCOL5A1 降低了 SLC7A11 的表达，通过 miR-1287-5p 共转染，这种趋势被消除。挽救实验进一步表明，circCOL5A1 敲低通过 miR-1287-5p/SLC7A11 减轻 CRC 细胞恶性表型。此外，干扰 circCOL5A1 减少了体内 CRC 的生长。circCOL5A1 通过 miR-1287-5p/SLC7A11 在 CRC 中发挥致癌基因作用。
