Serum CCAT2 as a biomarker for adjuvant diagnosis and prognostic prediction of cervical cancer

Growing evidence indicates that lncRNA colon cancer-associated transcript 2 (CCAT2) is associated with cancers. However, the clinical value of CCAT2 in cervical cancer (CC) remains unclear. In this study, serum CCAT2 level was detected by real-time quantitative PCR (RT-qPCR). Carbohydrate antigen 125 (CA125) and squamous-cell carcinoma antigen (SCC) were detected by electrochemiluminescence. A receiver operating characteristic (ROC) curve was utilized to estimate the diagnostic efficiency of CCAT2. Kaplan-Meier survival analysis and univariable and multivariable analyses were performed to assess the prognostic value of CCAT2. The relative expression level of CCAT2 in primary CC patients was significantly higher than that in cervical intraepithelial neoplasias (CIN) patients and healthy controls (both P < 0.001). CCAT2 relative expression was positively correlated with tumor Federation of Gynecology and Obstetrics (FIGO) stage, SCC-Ag and lymph node metastasis (LNM) (all P < 0.05). CCAT2 expression in recurrent/metastatic CC was significantly higher compared with primary CC (P < 0.0001) or operated CC (P < 0.0001) and during follow-up, CCAT2 expression was increased before surgery and decreased significantly after surgery (P < 0.0001). Furthermore, the overall survival rate of CC patients with high CCAT2 expression group markedly decreased as compared with that of low CCAT2 expression group (P = 0.026). Univariate analyses indicated that CCAT2 was a poor prognostic factor associated with overall survival (OS). Our study indicates that CCAT2 may be valuable in complementary diagnosis and monitoring of progression and prognosis of CC patients. Combined detection of CCAT2, CA125 and SCC can greatly improve the diagnostic efficiency of primary CC.