Although both of MMP-9 [28, 62] and uPA [29] were demonstrated previously activated by AREG in HNSCC invasion and metastasis, based on our microarray data and qRT-PCR results, only uPA showed significant decreases in this research, when AREG was suppressed by ectopic miR-34a. The gene discussed is PLAU; the disease is head and neck squamous cell carcinoma.