CAPN2 and cancer: Besides its role in microvesiculation, the calpains are an important family of proteases in cancer, whose abnormal expression has been implicated in various cancers, and which may be a factor in determining sensitivity to cancer therapy41; indeed m-calpain (calpain II) cDNA expression was increased by 20% in localized and 40% in metastatic prostate tumors compared to benign prostate and may be implicated in tumorigenesis42.