Moreover, the expression of HIF-1α was significantly correlated with OSCC TNM staging including tumor size and lymph node metastasis  (p < 0.05; Additional file 1: Table S1). Collectively, these results suggest that miRNA-18a and -20a are direct targets of HIF-1α in OSCC although their expression patterns differed. This evidence concerns the gene HIF1A and neoplasm.