ADAM9 and cancer: Recently, highly expressed ADAM9 was detected in breast cancer (9), liver cell carcinoma (10), gastric cancer (11), pancreatic ductal adenocarcinoma (12), prostate cancer (13), renal cell carcinoma (14) and cervical squamous carcinoma (15), correlating with cancer progression, metastasis and predicting a shortened survival time in patients (9–15).