Serum Circular FoxO3a Serves as a Novel Prognostic Biomarker in Squamous Cervical Cancer

PURPOSE: Circular RNAs (circRNAs) are novel type of noncoding RNAs that play important roles and serve as noninvasive biomarkers in various cancers. In the present study, we focused on circFoxO3a and aimed to investigate its prognostic value as a novel serum biomarker for squamous cervical cancer (SCC). PATIENTS AND METHODS: Our study included 103 SCC patients from Obstetrics and Gynecology Hospital of Fudan University. Expression levels of circFoxO3a in the serum of patients with SCC were examined by reverse transcription‑quantitative PCR (RT‑qPCR). The correlation between serum circFoxO3a expression and clinicopathologic factors was analyzed. The Kaplan–Meier method and multivariate Cox regression analysis were applied to evaluate the independent prognostic factors for SCC. A prognostic predictive nomogram was constructed using R software. RESULTS: Levels of serum circFoxO3a were decreased in SCC patients compared with controls. Low expression of circFoxO3a was correlated with deeper stromal invasion and positive lymph node metastasis. Moreover, SCC patients with lower expression of serum circFoxO3a showed poorer prognosis, including both overall survival (OS) and recurrence-free survival (RFS). Multivariate Cox analysis indicated low serum circFoxO3a levels to be an unfavorable prognostic factor for both OS and RFS, independent of positive lymph node metastasis. Notably, the predictive nomogram we established further confirmed that serum circFoxO3a is a useful tool for predicting survival in SCC. CONCLUSION: Altogether, our findings demonstrated that serum circFoxO3a could serve as a potential novel noninvasive predictive prognostic biomarker and therapeutic target for SCC.