College of Laboratory Medicine, Dalian Medical University, 9 Lushunnan Road Xiduan, Dalian, 116044, Liaoning Province, China.
Department of General Surgery, the Second Affiliated Hospital of Dalian Medical University, Dalian, 116027, Liaoning Province, China.
J Exp Clin Cancer Res. 2018 Dec 14;37(1):316. doi: 10.1186/s13046-018-0994-x.
Long non-coding RNAs (LncRNAs) emerging as pivotal marker in the procession of cancer, including colorectal cancer (CRC). Abnormal O-glycosylation is a crucial modification during cancer malignancy. The aim of this work is to analyze the alteration of O-glycosylation involved in CRC progression.
qRT-PCR is utilized to screen the differential linc01296 expression in CRC tissues and cell lines. Functionally, CRC cell proliferation, aggressiveness and apoptosis are measured through relevant experiments, including CCK8 assay, colony formation assay, transwell assay, western blot and flow cytometry. Dual-luciferase reporter gene assay and RIP assay confirm the direct interaction between linc01296 and miR-26a. The xenografts and liver metatstatic nude mice models are established to show the inner effect of linc01296.
Differential expression of linc01296 is confirmed and closely correlated with the malignancy of CRC cell lines and poor clinical prognosis. Moreover, alteration of linc01296 affects CRC cell proliferation, metastasis and chemoresistance to 5-fluorouracil (5-FU) in vitro. Mechanically, linc01296 acts as a direct target of miR-26a, and thereby influenced CRC malignancy. Our investigation corroborates that linc01296 functions as an endogenous sponge of miR-26a to regulate mucin1 (MUC1) expression, catalyzed by GALNT3, which modulates the activity of PI3K/AKT pathway. Interestingly, upregulated linc01296 promotes the tumorigensis, liver metastasis and chemoresistance of CRC cell lines in vivo.
These new findings indicate that linc01296/miR-26a/GALNT3 axis involves in the progression of CRC cells, illuminating the possible mechanism mediated by O-glycosylated MUC1 via PI3K/AKT pathway. This work renders potential diagnostic biomarkers and prospective therapeutic targets for CRC.
长非编码 RNA（LncRNAs）作为癌症发生过程中的关键标志物而出现，包括结直肠癌（CRC）。异常的 O-糖基化是癌症恶性转化过程中的重要修饰。本工作旨在分析 CRC 进展中涉及的 O-糖基化改变。
qRT-PCR 用于筛选 CRC 组织和细胞系中差异表达的 linc01296。通过 CCK8 测定、集落形成测定、transwell 测定、western blot 和流式细胞术等相关实验，测量 CRC 细胞增殖、侵袭和凋亡等功能。双荧光素酶报告基因检测和 RIP 检测证实 linc01296 与 miR-26a 之间的直接相互作用。建立异种移植和肝转移裸鼠模型以显示 linc01296 的内在作用。
证实 linc01296 的差异表达与 CRC 细胞系的恶性程度和不良临床预后密切相关。此外，linc01296 的改变会影响 CRC 细胞在体外的增殖、转移和对 5-氟尿嘧啶（5-FU）的化疗耐药性。机制上，linc01296 作为 miR-26a 的直接靶标，从而影响 CRC 恶性程度。我们的研究证实，linc01296 作为 miR-26a 的内源性海绵，调节 GALNT3 催化的粘蛋白 1（MUC1）表达，从而调节 PI3K/AKT 通路的活性。有趣的是，上调的 linc01296 促进 CRC 细胞系在体内的肿瘤发生、肝转移和化疗耐药性。
这些新发现表明，linc01296/miR-26a/GALNT3 轴参与 CRC 细胞的进展，阐明了通过 PI3K/AKT 通路介导的 O-糖基化 MUC1 可能的机制。这项工作为 CRC 提供了潜在的诊断生物标志物和有前途的治疗靶点。
