Long non-coding RNA PICSAR serves as a non-invasive biomarker for the diagnosis and prognosis of cutaneous squamous cell carcinoma.

Cutaneous squamous cell carcinoma (cSCC) is one of the most common malignant tumors in dermatology, and its incidence is increasing year by year. Long non-coding RNAs (lncRNAs) play vital roles in the processes of various malignant tumors. This study aimed to evaluate the expression of long non-coding RNA PICSAR and investigate whether serum PICSAR could serve as a biomarker for the diagnosis and prognosis of cSCC. The expression level of PICSAR was measured using quantitative Real-Time PCR. The diagnostic value of PICSAR was evaluated by receiver operating characteristic (ROC) analysis. Survival curves were established using the Kaplan-Meier method, and the log-rank test was used to compare differences between the two curves. Prognostic value of PICSAR was confirmed by Cox regression analysis. The expression of PICSAR was upregulated in serum of cSCC patients and tumor tissues of patients. Additionally, serum PICSAR expression had relatively high diagnostic accuracy for the screening of cSCC. Moreover, PICSAR expression was correlated with tumor size, grade of differentiation and TNM stages, and significantly increased in cSCC patients with poor tumor differentiation and cSCC patients with III-IV TNM stage. Furthermore, patients with high PICSAR expression had lower overall survival than the patients with low PICSAR expression, and PICSAR expression was an independent prognostic factors for cSCC patients. The results of this study indicated that PICSAR was upregulated in cSCC patients and tumor tissues and might serve as a non-invasive biomarker for the diagnosis and prognosis of cSCC patients.