CCNE1 Promotes Progression and is Associated with Poor Prognosis in Lung Adenocarcinoma

Background: Mounting evidence has shown that Cyclin E1 (CCNE1) facilitates various carcinoma progression, but its function in lung adenocarcinoma (LUAD) remains unclear. Objectives: Our study aims to explore the significance of CCNE1 in clinical progression and study its biological functions in LUAD. Methods: CCNE1 expressions in LUAD specimens and cells were detected through quantitative real-time polymerase chain reaction (qRT-RCR) and western blot. An immunohistochemistry technique was used to detect CCNE1 expression to explore its association with clinical parameters. The LUAD cells with stable knockdown of CCNE1 were constructed by small interfering RNA. The effect of CCNE1 on LUAD cells proliferation and apoptosis was evaluated through Cell Counting Kit-8 (CCK-8), colony formation, and Annexin V/propidium iodide (AV-PI) assays, respectively. The cell migration and invasion were evaluated by Wound-healing and Transwell assays, respectively. The xenograft and lung metastasis mouse models were introduced to analyze how CCNE1 knockdown affects tumor growth and tumor metastasis. Results: CCNE1 expression was upregulated in LUAD tissue and cells. CCNE1 knockdown inhibited LUAD cellular malignant behavior in vitro and reduced tumor growth and metastasis in vivo. High expression of CCNE1 was correlated with big tumor size, cancer stage, lymph node metastasis, and poor prognosis. Conclusion: CCNE1 overexpression promotes LUAD growth, metastasis, and forebode poor prognosis: it can serve as a new prognostic marker of LUAD.