Identification and clinical validation of gene signatures with grade and survival in head and neck carcinomas

This study aimed to explore gene expression profiles that drive malignancy from low- to high-grade head and neck carcinomas (HNC), as well as to analyze their correlations with survival. Gene expressions and clinical data of HNC were downloaded from the Gene Expression Omnibus (GEO) repository. The significantly differential genes (SDGs) between low- and high-grade HNC were screened. Cox regressions were performed to identify prognostic SDGs of progression-free survival (PFS) and disease-specific survival (DSS). The genes were experimentally validated by RT-PCR in clinical tissue specimens. Thirty-five SDGs were identified in 47 low-grade and 30 high-grade HNC samples. Cox regression analyses showed that CXCL14, SLC44A1, and UBD were significantly associated with DSS, and PPP2R2C and SLC44A1 were associated with PFS. Patients were grouped into high-risk or low-risk groups for prognosis based on gene signatures. High-risk patients had significantly shorter DSS and PFS than low-risk patients (P=0.033 and P=0.010, respectively). Multivariate Cox regression showed HPV (P=0.033), lymph node status (P=0.032), and residual status (P<0.044) were independent risk factors for PFS. ROC curves showed the risk score had better efficacy to predict survival both for DSS and PFS (AUC=0.858 and AUC=0.901, respectively). The results showed CXCL14 and SLC44A1 were significantly overexpressed in the low-grade HNC tissues and the UBD were overexpressed in the high-grade HNC tissues. Our results suggested that SDGs had different expression profiles between the low-grade and high-grade HNC, and these genes may serve as prognostic biomarkers to predict survival.