Enzymes, isozymes, and enzyme variants in the diagnosis of cancer. A short review

Abstract

Changes of enzyme activity in tissues, body fluids, and serum as well as changes of isozymes and enzyme variants in patients with malignancy suggest that these parameters may be used in the diagnosis of some types of cancer. A review of available information indicates that: (1) changes of serum enzymes in patients with malignancies relate to the presence of a heavy tumor burden or of metastases, and cannot be utilized for the early diagnosis of malignancies; (2) changes in isozyme patterns and newly developed enzyme variants may be of greater diagnostic value, although possibly not in the early diagnosis of cancer; (3) study of enzymatic activity in body fluids may offer valuable help in specific situations; and (4) occasionally, determination of enzymes may be of help in establishing susceptibility to malignancies.

Effect of Cisplatin on the Lactate Dehydrogenase Activity and its Isozyme Pattern in Dalton's Lymphoma Bearing Mice.

“…Enzymatic changes may reflect the overall changes in metabolism that occur in malignancy (Stefanini 1985). In present study, as compared to normal animals, more than two fold increase in serum LDH activity has been observed in Dalton's lymphoma-bearing mice (Fig.…”

“…1A) which may suggest the release of LDH in the tissues of tumor-bearing hosts. In general a higher rate of glycolysis has been reported in tumor cells (Warburg 1956, Yesher 1978, and it has been suggested that the rapid turnover of malignant cells should release ecto-and endo-enzymes into the blood stream (Stefanini 1985). The higher LDH activity in tumor-bearing mice was observed in liver also, the main site of glycolysis, (Fig.…”

“…Lactate dehydrogenase (LDH, EC 1.1.1.27), the terminal enzyme in the anaerobic glycolysis, catalyses a reversible reaction of pyruvate to lactate. Increased activity of LDH has been reported in testicular cancer (Lippert and Javadpour 1981), cancerous breast (Stefanini 1985) and pulmonary tissue (Yesher 1978). Isoenzyme or isozyme determinations of the particular enzyme are becoming widely used means of detecting specific tissue specificity/disturbances.…”

Prognostic factors and survival in chronic myelomonocytic leukaemia (CMML)

“…Statistical relationships for the data were assessed using significant (P=0.013) as a prognostic factor (Figure 4) with Spearmans non-parametric rank correlation coefficient the high count group having a median survival from (Table,1 Serum lysozyme was divided into two groups (<2,500 and Survival data >2,500 u ml-1); a cut-off point selected arbitrarily as five times the normal upper limit, the low lysozyme group Survival was calculated using the Kaplan-Meier method to surviving longer than those with levels exceeding cancer death and this gave a median survival for all patients 2,500uml-' (P=0.028; Figure 5). haemopoietic) generally (Ho et al, 1982;Stefani, 1985;Scott et al, 1986 apart from the obvious benefits of having prognostic (Norfolk etdat., 1985).…”

Role of Prosopis cineraria against N-nitrosodiethylamine-induced liver tumor in rats with reference to marker enzymes and nucleic acid contents

“…Change in metabolism that occurs during malignancy (Stefanini, 1985) reflected by the abnormal variation in the marker enzymes. Cancer marker enzymes functioning as an indicator of cancer response to therapy.…”