Department of Oncology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China.
Department of Colorectal Surgery, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China.
Oncogene. 2022 Jan;41(5):692-703. doi: 10.1038/s41388-021-02066-z. Epub 2021 Nov 24.
N6-methyladenosine (m6A), the most abundant mRNA modification in mammals, is involved in the metabolism of mRNA. KIAA1429 is regarded as the largest m6A methyltransferase and plays an important role in m6A modification. However, the prognostic value and function of KIAA1429 in colorectal cancer (CRC) are unclear. Quantitative real-time PCR and immunohistochemical assays were performed to evaluate the expression of KIAA1429 in CRC tissues. Kaplan-Meier survival curves and log-rank tests were used to assess the association between KIAA1429 expression and the prognosis of patients with CRC. CCK-8 assays, colony formation assays, cell cycle assays, and xenograft experiments were performed to investigate the effect of KIAA1429 on cell proliferation. RNA immunoprecipitation, methylated RNA immunoprecipitation assays, and RNA stability assays were conducted to explore the underlying mechanism. KIAA1429 was significantly upregulated in CRC tissues compared with adjacent normal tissues. Patients with higher expression of KIAA1429 had shorter overall survival than those with lower expression. Functionally, KIAA1429 promoted CRC cell proliferation in vitro and in vivo. Mechanistically, KIAA1429 negatively regulated the expression of WEE1 by decreasing its stability in an m6A-independent manner by binding to the third segment in the 3'-UTR of WEE1 mRNA. Moreover, butyrate decreased the expression of KIAA1429 by downregulating the level of the transcription factor NFκB1. Our findings indicated that KIAA1429 plays an oncogenic role in CRC cells by inhibiting the expression of WEE1 in an m6A-independent manner and is associated with poor survival in CRC patients. These results suggested that KIAA1429 might be a potential prognostic marker for CRC.
N6-甲基腺苷(m6A)是哺乳动物中最丰富的 mRNA 修饰物,参与 mRNA 的代谢。KIAA1429 被认为是最大的 m6A 甲基转移酶,在 m6A 修饰中发挥重要作用。然而,KIAA1429 在结直肠癌(CRC)中的预后价值和功能尚不清楚。定量实时 PCR 和免疫组织化学检测评估了 CRC 组织中 KIAA1429 的表达。Kaplan-Meier 生存曲线和对数秩检验用于评估 KIAA1429 表达与 CRC 患者预后的相关性。CCK-8 检测、集落形成检测、细胞周期检测和异种移植实验用于研究 KIAA1429 对细胞增殖的影响。RNA 免疫沉淀、甲基化 RNA 免疫沉淀检测和 RNA 稳定性检测用于探索潜在的机制。与相邻正常组织相比,CRC 组织中 KIAA1429 明显上调。KIAA1429 表达较高的患者总生存期短于表达较低的患者。功能上,KIAA1429 在体外和体内促进 CRC 细胞增殖。机制上,KIAA1429 通过结合 WEE1 mRNA 3'-UTR 第三片段以 m6A 非依赖的方式降低其稳定性,从而负调控 WEE1 的表达。此外,丁酸盐通过下调转录因子 NFκB1 的水平来降低 KIAA1429 的表达。我们的研究结果表明,KIAA1429 通过以 m6A 非依赖的方式抑制 WEE1 的表达在 CRC 细胞中发挥致癌作用,并与 CRC 患者的不良生存相关。这些结果表明,KIAA1429 可能是 CRC 的潜在预后标志物。