Sun Yat-sen University Cancer Center, State Key Laboratory of Oncology in South China and Collaborative Innovation Center for Cancer Medicine, Guangzhou, China.
Department of Clinical Laboratory Medicine, Sun Yat-sen University Cancer Center, Guangzhou, China.
Cell Death Differ. 2023 Oct;30(10):2213-2230. doi: 10.1038/s41418-023-01225-x. Epub 2023 Sep 19.
C-Myc overexpression contributes to multiple hallmarks of human cancer but directly targeting c-Myc is challenging. Identification of key factors involved in c-Myc dysregulation is of great significance to develop potential indirect targets for c-Myc. Herein, a collection of long non-coding RNAs (lncRNAs) interacted with c-Myc is detected in pancreatic ductal adenocarcinoma (PDAC) cells. Among them, lncRNA BCAN-AS1 is identified as the one with highest c-Myc binding enrichment. BCAN-AS1 was abnormally elevated in PDAC tumors and high BCAN-AS1 level was significantly associated with poor prognosis. Mechanistically, Smad nuclear-interacting protein 1 (SNIP1) was characterized as a new N-methyladenosine (mA) mediator binding to BCAN-AS1 via recognizing its mA modification. mA-modified BCAN-AS1 acts as a scaffold to facilitate the formation of a ternary complex together with c-Myc and SNIP1, thereby blocking S phase kinase-associated protein 2 (SKP2)-mediated c-Myc ubiquitination and degradation. Biologically, BCAN-AS1 promotes malignant phenotypes of PDAC in vitro and in vivo. Treatment of metastasis xenograft and patient-derived xenograft mouse models with in vivo-optimized antisense oligonucleotide of BCAN-AS1 effectively represses tumor growth and metastasis. These findings shed light on the pro-tumorigenic role of BCAN-AS1 and provide an innovant insight into c-Myc-interacted lncRNA in PDAC.
C-Myc 过表达导致多种人类癌症的特征,但直接靶向 C-Myc 具有挑战性。鉴定参与 C-Myc 失调的关键因素对于开发 C-Myc 的潜在间接靶标具有重要意义。在此,在胰腺导管腺癌 (PDAC) 细胞中检测到与 C-Myc 相互作用的一组长链非编码 RNA (lncRNA)。其中,lncRNA BCAN-AS1 被鉴定为与 C-Myc 结合富集度最高的一种。BCAN-AS1 在 PDAC 肿瘤中异常升高,高水平的 BCAN-AS1 与预后不良显著相关。在机制上,Smad 核相互作用蛋白 1 (SNIP1) 被表征为一种新的 N6-甲基腺苷(mA) 调节剂,通过识别其 mA 修饰与 BCAN-AS1 结合。mA 修饰的 BCAN-AS1 作为支架,与 C-Myc 和 SNIP1 一起促进三元复合物的形成,从而阻断 SKP2 介导的 C-Myc 泛素化和降解。在生物学上,BCAN-AS1 促进了 PDAC 的体外和体内恶性表型。用体内优化的 BCAN-AS1 反义寡核苷酸治疗转移异种移植和患者来源的异种移植小鼠模型,可有效抑制肿瘤生长和转移。这些发现揭示了 BCAN-AS1 的促肿瘤作用,并为 PDAC 中 C-Myc 相互作用的 lncRNA 提供了新的见解。