Cytokeratin (high molecular weight) can recognize cytokeratin 1, cytokeratin 5, cytokeratin 10 and cytokeratin 14. In normal tissues, cytokeratin (high molecular weight) is mainly expressed in squamous epithelium, ductal epithelium and other stratified epithelium. It’s also expressed in lung squamous cell carcinoma, breast cancer, pancreatic cancer, cholangiocarcinoma and bladder transitional cell carcinoma. This antibody can recognize the basal cells of benign prostatic duct, but it is not expressed in prostate cancer. It is often used in combination with p63 and P504S in the judge of prostate cancer.