Lactate Dehydrogenase Isoenzymes Ratio Is a Valuable Tool for Stage Diagnosis and Monitoring Therapy of Chronic Leukemia

Recently majority of researches focus on the biochemical markers for prognosis, preclinical diagnosis, monitoring therapy and tumor recurrency diagnosis.Among these biomarkers, enzymes, isoenzymes and enzyme variants have distinct importance. Lactate dehydrogenase (LOH), an old enzyme reborn in the diagnosis of various cancers, and its isoenzymes have clinical importance. Among blood cancers, leukemias have more incidance and are devided into two major groups of acute and chronic leukemia. In this study, total LDH, its isoenzymes and also the ratio of its isoenzymes were investigated in two groups of chronic myeloblastic leukemia (CML) and chronic lymphoblastic leukemia (CLL) patients (25 CML and 25 CLL).This enzyme and its isoenzymes were also studied in 50 age and sex matched healthy controls. We used instrumental commercial kits for the total LDH, and isoelectrofocusing on polyacJYlamide gels for the isoenzymes..The results showed that the total LOH in the CML patients was significantly higher than controls (454.4±11.9 versus 174.4±27.5). However the CLL group did not have any statistical difference with the healthy controls (p:s0.01).In the CML patients LOH3 isoenzyme was veJY high compared with the controls (29.4±2.97 versus 17±3.11 P:s0.001). Nevertheless, in the CLL group the ratio of isoenzymes was considerable, so that the LDH isozymes ratios were remarkably increased in the patients compared with the controls. But LDHiLDHl ratio for the eLL group was 2.33±89 and had much difference with the control group (0.36±0.08, P:sO.OOll). It is concluded that the LOH and its isoenzymes could be used for clinical diagnosis of the chronic leukemia, specially when other markers have poor clinical value.