Zhao Shi-Yu, Wang Zhi, Wu Xiang-Bai, Zhang Shuai, Chen Qiao, Wang Dong-Dong, Tan Qiong-Feng
Department of Colorectal Anal Surgery, China Three Gorges University Colorectal Disease Research Institute, Yichang Key Laboratory of Precise Diagnosis and Treatment of Colorectal Cancer, The Second Hospital of China Three Gorges University, Yichang, Hubei, China.
Department of Gastrointestinal Surgery, The Central Hospital of Enshi Tujia and Miao Autonomous Prefecture, Enshi, Hubei, China.
Kaohsiung J Med Sci. 2022 May;38(5):403-414. doi: 10.1002/kjm2.12503. Epub 2022 Feb 11.
Accumulating evidence indicates that long noncoding RNAs (lncRNAs) act as tumor promoters or suppressors in various types of cancer. Previous investigations suggest that ceramide synthase 6 (CERS6) antisense RNA 1 (CERS6-AS1) acts as an oncogene in breast cancer; however, its role in colorectal cancer is unknown. This study aimed to explore the molecular mechanism of CERS6-AS1 in colorectal cancer. Gene expression in colorectal cancer was examined using reverse transcription-quantitative polymerase chain reaction and western blot analyses. The viability and proliferation of colorectal cancer cells were measured by Cell Counting Kit-8 assays and colony formation assays. The migratory and invasive capacities of the colorectal cancer cells were assessed by Transwell assay. Cell stemness was examined by sphere-formation assay. Mechanistically, RNA pull-down assays, RNA immunoprecipitation assays, and luciferase reporter assays were performed to explore the relationship among CERS6-AS1, miR-15b-5p and spectrin beta, non-erythrocytic 2 (SPTBN2). Moreover, a xenograft tumor model was established to investigate the role of CERS6-AS1 in vivo. We found that CERS6-AS1 and SPTBN2 were highly expressed in colorectal cancer tissues and cells. CERS6-AS1 depletion inhibited cell viability, proliferation, migration, and invasion; the epithelial-mesenchymal transition process and stemness. It suppressed xenograft tumor growth in colorectal cancer. Moreover, SPTBN2 levels were positively regulated by CERS6-AS1 and negatively regulated by miR-15b-5p in colorectal cancer cells. Rescue assays revealed that SPTBN2 reversed the inhibitory effect of CERS6-AS1 deficiency on the malignant behaviors of colorectal cancer cells. Overall, the lncRNA CERS6-AS1 facilitates malignant phenotypes of colorectal cancer cells by targeting miR-15b-5p to upregulate SPTBN2.
越来越多的证据表明，长链非编码RNA（lncRNA）在各种类型的癌症中充当肿瘤促进因子或抑制因子。先前的研究表明，神经酰胺合酶6（CERS6）反义RNA 1（CERS6-AS1）在乳腺癌中作为一种癌基因发挥作用；然而，其在结直肠癌中的作用尚不清楚。本研究旨在探讨CERS6-AS1在结直肠癌中的分子机制。采用逆转录定量聚合酶链反应和蛋白质免疫印迹分析检测结直肠癌中的基因表达。通过细胞计数试剂盒-8检测和集落形成试验测定结直肠癌细胞的活力和增殖。通过Transwell试验评估结直肠癌细胞的迁移和侵袭能力。通过成球试验检测细胞干性。从机制上来说，进行了RNA下拉试验、RNA免疫沉淀试验和荧光素酶报告试验，以探究CERS6-AS1、miR-15b-5p和非红细胞β-血影蛋白2（SPTBN2）之间的关系。此外，建立了异种移植肿瘤模型以研究CERS6-AS1在体内的作用。我们发现CERS6-AS1和SPTBN2在结直肠癌组织和细胞中高表达。CERS6-AS1的缺失抑制了细胞活力、增殖、迁移和侵袭；上皮-间质转化过程和干性。它抑制了结直肠癌异种移植肿瘤的生长。此外，在结直肠癌细胞中，SPTBN2的水平受到CERS6-AS1的正调控和miR-15b-5p的负调控。挽救试验表明，SPTBN2逆转了CERS6-AS1缺陷对结直肠癌细胞恶性行为的抑制作用。总体而言，lncRNA CERS6-AS1通过靶向miR-15b-5p上调SPTBN2促进结直肠癌细胞的恶性表型。
