lncRNA CERS6-AS1 promotes cell proliferation, migration, invasion, and epithelial-mesenchymal transformation of lung adenocarcinoma by sponging miR-424-5p upregulates ANLN expression
Authors: Zhuo Ting , Wu Zuotao , Yang Chuyi , Li Zihao , Huang Hongyu , Gan Jinyan , Li Nijiao , Li Xiaohong , Lyu Jueqi , Wu Yanbin , Qin Shouming 
Published: September 2023

Background
Long noncoding RNA (lncRNA) plays a crucial role in tumor genesis and progression, exerting strong regulation over cancer cell growth. Among these lncRNAs, one of particular concern is lncRNA CERS6 antisense RNA 1 (CERS6-AS1). Functioning as an oncogene, it exhibits significant upregulation and promotes tumor progression in various types of tumors. However, the exact functional significance and underlying molecular mechanism by which CERS6-AS1 operates in the context of lung adenocarcinoma (LUAD) remain unclear.
Methods
Expression levels of CERS6-AS1 in both LUAD and normal tissues were examined using RNA data obtained from the Cancer Genome Atlas (TCGA). To validate these findings, the expression of CERS6-AS1 was further assessed in clinical samples and lung cancer cell lines using real-time quantitative polymerase chain reaction (RT-qPCR). Different databases such as TargetScan, ENCORI, and StarBase were utilized to predict potential micro-RNAs (miRNAs) that could bind to CERS6-AS1. Experimental validation of the functional implications of both CERS6-AS1 and miR-424-5p in cell proliferation, migration, and invasion capacity was carried out using cell counting kit-8, wound healing, and Transwell assays. The interaction between CERS6-AS1 and miR-424-5p was investigated through a luciferase assay. Furthermore, multiple databases were used to identify potential downstream genes associated with the regulatory axis of CERS6-AS1/miR-424-5p. A bioinformatics analysis was performed to evaluate the impact of increased expression of the downstream gene ANLN on various factors, including immune cell infiltration, tumor mutation burden, response to chemotherapy, and immunotherapy.
Results
CERS6-AS1 was observed to be upregulated in both LUAD tissue samples and lung cancer cell lines. To investigate the functional relevance of CERS6-AS1, knockdown experiments were conducted in A549 and H1299 cell lines. The knockdown of CERS6-AS1 significantly inhibited cell proliferation, invasion, migration, and epithelial-mesenchymal transition (EMT) in these cell lines. Notably, there was a prominent upregulation of miR-424-5p expression in cells where CERS6-AS1 was knocked down. Co-transfection of si-CERS6-AS1-2 and miR-424-5p inhibitors into lung cancer cells restored the cytological behavior inhibited by CERS6-AS1 knockdown. These findings provide evidence for a targeted relationship between CERS6-AS1 and miR-424-5p. Anillin (ANLN) has been identified as a potential target gene for miR-424-5p, which serves as a prognostic and immunobiomarker associated with immune cell infiltration and tumor mutational burden in LUAD. Additionally, ANLN impacts the efficacy of chemotherapy and immunotherapy in LUAD patients.
Conclusion
This study unveils a novel regulatory mechanism in which CERS6-AS1 potentially influences ANLN expression by acting as a competitive sponge for miR-424-5p. This regulatory axis is implicated in the progression of lung adenocarcinoma, offering valuable insights for the diagnosis and treatment of this disease.