LAUSR

Abstract Background Few studies have directly investigated the differential expression of miRNA between low-tobacco and high-tobacco exposed HNSCC. The purpose of this study is to screen the differentially expressed miRNA and to investigate the clinical significance and potential biological mechanisms in above two groups of HNSCC. Methods The HNSCC datasets were obtained from TCGA database. Meanwhile, we collected 22 HNSCC patients in our hospital. The differentially expressed miRNAs between low-tobacco and high-tobacco exposed HNSCC were identified based on log2FC > 1 and FDR Results 30 differentially expressed miRNAs were identified between low-tobacco and high-tobacco exposed HNSCC. The patients with high expression of miR-499a had lower overall survival than those with low expression of miR-499a in high-tobacco exposed HNSCC (p = 0.02). Multivariate Cox regression showed that high expression of miR-499a was an independent risk factor for prognosis of high-tobacco exposed HNSCC (HR = 3.26, p = 0.03). Chi-square test showed that miR-499a was related to N stage in high-tobacco exposed HNSCC (p  Conclusions 30 differentially expressed miRNAs are identified between low-tobacco and high-tobacco exposed HNSCC. In high-tobacco exposed HNSCC, highly expressed miR-499a may promote lymph node metastasis by down-regulating one or more of ZNRF1, AEBP2, NUS1, resulting in shortened patient survival. Legal entity responsible for the study The authors. Funding Has not received any funding. Disclosure All authors have declared no conflicts of interest.