Furthermore, although there were differences in age at initial diagnosis among the low-tobacco, medium-tobacco, and high-tobacco exposed HNSCC, the additional analysis indicated that the differential expression of hsa-miR-499a, AEBP2, and ZNRF1 in HNSCC with low, medium, and high tobacco exposure was due to the different lifetime tobacco exposure value, rather than the different age at initial diagnosis. The gene discussed is AEBP2; the disease is head and neck squamous cell carcinoma.