MMP13 and metastatic malignant neoplasm in the lymph nodes: It was recently shown that leptin, which uses ROCK as a critical signal mediator (Huang et al, 2012), induces migration and invasion of human pancreatic cells via MMP13 up‐regulation, while increased MMP13 expression in patients was associated with lymph node metastasis and pathological stage (Fan et al, 2015).