Abstract
Human lactate dehydrogenase (1,1,1,27-LDH) isoenzymes were determined in human prostatic carcinoma cell lines. The isoenzymes LDH-4/LDH-5 were identified and quantified in the serum of athymic mice bearing the human prostatic carcinoma cell lines PC-3, PC-3/M and DU 145 subcutaneously. The amounts of the slowly migrating isoenzymes released by the solid tumors correlated with increasing tumor volume and tumor weight. These correlations indicate that the human LDH-4/LDH-5 isoenzymes are useful parameters for monitoring the presence and growth of prostatic cancer in the athymic animal model.