Cleavage polyadenylation specificity factor (CPSF) is the core component of the 3'-end processing complex, which determines the site of 3'-end cleavage interactions of specific sequence elements within pre-mRNAs. The present study revealed that all members of the CPSF complex were overexpressed in lung cancer tissue from The Cancer Genome Atlas (TCGA) Lung Cancer Cohort compared with normal lung tissue. Analysis of overall survival and recurrence-free survival verified that only CPSF3 was associated with prognosis and recurrence of lung adenocarcinoma (LUAD), and thus could be a promising biomarker. Additionally, receiver operating characteristic curve analysis revealed that CPSF3 may function as a diagnostic biomarker to distinguish between two histological subtypes of non-small cell lung cancer. Furthermore, analysis of the association of CPSF3 expression with clinicopathological parameters indicated that CPSF3 was associated with smoking history, tumor diameter, lymph node metastasis, clinical stage and radiation therapy in LUAD. Additionally, analysis of the DNA methylation data of the TCGA-LUAD Cohort revealed that CPSF3 DNA CpG sites (cg12057242 and cg25739938) were generally hypomethylated in LUAD compared with normal lung tissue. Correlation analysis identified the CPSF3 DNA CpG site cg25739938 to be negatively correlated with CPSF3 expression, while no correlation was identified with cg12057242. In addition, correlation analysis demonstrated that the overexpression of CPSF3 was correlated with CPSF3 DNA copy number variants (CNAs). The findings indicate that abnormal expression of CPSF3 may be caused by DNA CNAs; and DNA hypermethylation and function may be a promising diagnostic and prognostic indicator for LUAD.
Keywords: The Cancer Genome Atlas; bioinformatics analysis; biomarker; cleavage and polyadenylation specific factor 3; cleavage and polyadenylation specificity factor; lung adenocarcinoma; non-small cell lung cancer.