Our results showed that enforced expression of miR-128 inhibited the HNSCC cell proliferation and tumor xenograft growth by mediating the expression of BMI-1, BAG-2, BAX, H3f3b, and Paip2 mRNAs, suggesting that miR-128 might act as a tumor suppressor. The gene discussed is PAIP2; the disease is head and neck squamous cell carcinoma.