Fig. 1

NEDD8 is upregulated and serves as a poor prognostic marker in OSCC. A and B Boxplots for the transcriptional profiling of NEDD8 in normal tissue (NT) and primary tumor (PT) derived from TCGA head and neck cancer patients divided into nonoral cancer and oral cancer subtypes (A) and GSE42743 oral cancer patients (B). Student’s t test was used to analyze the statistical significance. C and D RT‒PCR results for NEDD8 and GAPDH mRNA levels in paired normal (N) and tumor (T) tissues derived from 14 OSCC patients (P1–P14) and obtained from the Taipei Medical University (TMU) biobank (C). The NEDD8 mRNA levels normalized to the respective GAPDH controls in 14 paired normal adjacent tissue (NAT) and primary tumor (PT) specimens are shown in D. A paired t test was used to analyze the statistical significance. E and F Kaplan‒Meier analyses using overall survival (OS), progression-free survival (PFS) and disease-free survival (DFS) probability under minimized log-rank p values for NEDD8 mRNA levels against TCGA head and neck cancer patients with nonoral cancer or oral cancer subtypes (E) and GSE42743 oral cancer patients (F). The inserts denote the proportion of the enrolled patients in each group