['Matrix metalloproteinase-11 (MMP-11) is reported to be overexpressed in several cancers and may contribute to tumorigenesis. The current study investigated the association between the clinicopathological characteristics and plasma level of MMP-11 in oral squamous cell carcinoma (OSCC) patients.', 'The plasma MMP-11 concentration was determined by ELISA on 330 male OSCC patients. In addition, the metastatic effects of the MMP-11 knockdown on the oral cancer cells were investigated by cell migration assay. Our results showed that the plasma MMP-11 levels were significantly higher in patients with advanced T status (p\u200a=\u200a0.001), lymph node metastasis (p\u200a=\u200a0.006) and higher TNM stages (p<0.001). Moreover, treatment with the MMP-11 shRNA exerted an inhibitory effect on migration in SCC9 oral cancer cells.'] Is high level of plasma matrix metalloproteinase-11 associated with clinicopathological characteristics in patients with oral squamous cell carcinoma?