TP53 and non-small cell lung carcinoma: To explore whether circSCAP functioned the same way in NSCLC cells with p53 mutation, we firstly detected the background level of p53 in all five NSCLC cell lines used in this study including two cell lines with wild-type p53 (A549 and H1650), two another cell lines with inactivating p53 mutation (PC9 and HCC827) and one cell line with p53 null mutation (H1299).