Serum long non-coding RNA LOC553103 as non-specific diagnostic and prognostic biomarker for common types of human cancer

Background: Circulating DNAs or RNAs in body liquid have emerged as useful and highly potential biomarkers for noninvasive diagnostic application. Our previous study had shown that LOC553103 was an oncogenic lncRNA, however, a systematic evaluation of LOC553103 as a diagnostic and prognostic biomarker for pan-cancer has not yet been demonstrated. Method: The expression data of LOC553103 were obtained from the quantitative real-time polymerase chain reaction (qRT-PCR) and The Cancer Genome Atlas (TCGA) database, respectively. The serum LOC553103 had a high diagnostic performance among the 15 types of human solid cancer. Result: The relative AUC of serum LOC553103 in cancer patients ranged from 0.826 to 0.966 compared to that in healthy subjects. Furthermore, high serum level of LOC553103 was closely related to advanced tumor pathological stages. Serum level of LOC553103 declined significantly in patients after therapy. Kaplan-Meier survival analysis of TCGA data revealed that the LOC553103 was negatively correlated with survival and was a globally predictive biomarker for solid tumors. Additionally, we evaluated the oncogenic function of LOC553103 in various tumor cells, in vitro. Conclusion: We concluded that circulating LOC553103 could serve as useful non-specific diagnostic biomarker for pan-cancer and prediction of treatment efficacy.