Among the 146 miR-31-5p and miR-31-3p gene targets, the low expression of seven (CACNB2: p = 0.0018; IL34: p = 0.0031; CGNL1: p = 0.0012; CNTN3: p = 0.0061; GAS7: p = 0.0093; HOPX: p = 0.0345; and PBX1: p = 0.0247) significantly predicted a worse prognosis in patients with HNSCC by Kaplan–Meier analysis (Figure 4 and Figure 5). The gene discussed is HOPX; the disease is head and neck squamous cell carcinoma.