Seven tissue-specific isozymes--lactate dehydrogenases A and B (LDHA and LDHB), esterases B2 and A4 (ESB2 and ESA4), creatine kinase B (CKB), and red blood cell and tissue forms of adenosine deaminases (ADA)--were examined in the human adenocarcinoma cell line LS174T and its subclones grown under a wide variety of conditions.