Mouse Monoclonal. Intended for in vitro diagnostic (IVD) use. Cytokeratin 5 and cytokeratin 6 are both high-molecular weight, basic keratins expressed in a range of normal tissues. CK 5/6 are positively seen in nearly 100% of malignant mesotheliomas and rarely seen in lung adenocarcinomas. CK5/6 can positively be seen in undifferentiated large-cell carcinoma, as well as squamous carcinoma. Fewer than 10% of carcinomas of breast, colon, and prostate stain positively for this marker. CK 5/6 have also been successfully as a myoepithelial cell marker in prostate. References 1. Ordonez NG, Am J Surg Pathol. 1998; 22(10):1215-1221 2. Ordonez NG, Am J Surg Pathol. 22(10):1203-1214 3. Cury PM, Butcher DW, et al. Mod Pathol. 2000; 13(2): 107-12 4. U.S. 29CFR 1910.1200, OSHA Hazard Communication and EC Directive 91/155/EC.